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Review

Post-Production Finishing Processes Utilized in 3D Printing Technologies

by
Antreas Kantaros
1,*,
Theodore Ganetsos
1,
Florian Ion Tiberiu Petrescu
2,*,
Liviu Marian Ungureanu
2 and
Iulian Sorin Munteanu
2
1
Department of Industrial Design and Production Engineering, University of West Attica, 12244 Athens, Greece
2
“Theory of Mechanisms and Robots” Department, Faculty of Industrial Engineering and Robotics, National University of Science and Technology Polytechnic Bucharest, 060042 Bucharest, Romania
*
Authors to whom correspondence should be addressed.
Processes 2024, 12(3), 595; https://doi.org/10.3390/pr12030595
Submission received: 12 February 2024 / Revised: 3 March 2024 / Accepted: 14 March 2024 / Published: 15 March 2024
(This article belongs to the Section Sustainable Processes)
Browse Figures
Versions Notes

Abstract

:
Additive manufacturing (AM) has revolutionized production across industries, yet challenges persist in achieving optimal part quality. This paper studies the enhancement of post-processing techniques to elevate the overall quality of AM-produced components. This study focuses on optimizing various post-processing methodologies to address prevalent issues such as surface roughness, dimensional accuracy, and material properties. Through an extensive review, this article identifies and evaluates a spectrum of post-processing methods, encompassing thermal, chemical, and mechanical treatments. Special attention is given to their effects on different types of additive manufacturing technologies, including selective laser sintering (SLS), fused deposition modeling (FDM), and stereolithography (SLA) and their dedicated raw materials. The findings highlight the significance of tailored post-processing approaches in mitigating inherent defects, optimizing surface finish, and enhancing mechanical properties. Additionally, this study proposes novel post-processing procedures to achieve superior quality while minimizing fabrication time and infrastructure and material costs. The integration of post-processing techniques such as cleaning, surface finishing, heat treatment, support structure removal, surface coating, electropolishing, ultrasonic finishing, and hot isostatic pressing (HIP), as steps directly within the additive manufacturing workflow can immensely contribute toward this direction. The outcomes displayed in this article not only make a valuable contribution to the progression of knowledge regarding post-processing methods but also offer practical implications for manufacturers and researchers who are interested in improving the quality standards of additive manufacturing processes.

1. Introduction

Additive manufacturing (AM) stands at the forefront of a manufacturing sector, disrupting conventional production methodologies by offering unprecedented flexibility, customization, and efficiency. This innovative technique builds objects layer by layer, guided by digital designs, which can range from prototypes to fully functional end-use parts [1,2]. Its adaptability across a wide spectrum of materials, including plastics, metals, ceramics, and even living cells, underscores its versatility and potential impact [3,4].
The transformative capabilities of AM extend across numerous industries, each harnessing its unique attributes to drive innovation. In aerospace, AM enables the fabrication of complex, lightweight components that optimize fuel consumption and structural integrity, leading to more efficient aircraft designs [5]. Medical applications capitalize on AM’s ability to create patient-specific implants, prosthetics, and biocompatible structures, revolutionizing treatment options and healthcare outcomes [6,7,8].
Beyond these sectors, automotive companies leverage AM for rapid prototyping, customized automotive parts, and streamlined supply chains [9,10,11]. Architects and designers explore its potential in creating intricate structures and models, pushing the boundaries of 3D design and fabrication [12,13]. Even the food industry experiments with AM to develop novel culinary experiences and personalized nutrition [14,15]. One of the most promising aspects of AM lies in its potential to reduce material waste [16]. Traditional manufacturing often generates excess material through subtractive processes, while AM builds objects with precision, using only the necessary materials, thereby promoting sustainability [17].
The evolution of AM continues to push boundaries, introducing advancements in materials science, and scale-up capabilities. Its integration into existing manufacturing ecosystems signifies a paradigm shift toward decentralized, on-demand production, promising a future where complex designs are effortlessly trans-lated into tangible products, fueling innovation across global industries [18,19]. Post-processing plays a pivotal role in transforming raw additively manufactured components into high-quality, functional parts ready for use across industries. While AM offers unparalleled design freedom and rapid prototyping capabilities, the produced parts often require refinement to meet stringent quality standards and functional requirements.
The reduction in post-processing requirements is further emphasized by the ability of AM technologies to optimize material usage. Traditional manufacturing processes may generate significant material waste due to subtractive methods or the need for additional fin ishing steps to correct imperfections. With AM techniques, materials are deposited precisely where needed while waste is minimized, aligning with the frame of sustainable manufacturing practices. This not only reduces environmental impact but also contributes to cost effectiveness by maximizing material utilization. Additionally, the digital nature of AM allows for seamless integration of design modifications without the need for extensive tooling changes. In traditional manufacturing and alterations to a products design often entail significant adjustments to molds and dies and or tooling and leading to increased downtime and costs. In contrast, AM can easily adapt to design changes by simply adjusting the digital model and facilitating rapid prototyping.
Post-processing encompasses a diverse range of techniques tailored to address in-herent limitations and enhance various aspects of the printed parts. It addresses challenges such as surface roughness, dimensional accuracy, mechanical properties, and surface finish that may arise during the AM process [20,21]. Surface finishing techniques, including polishing, sanding, or chemical treatments, aim to smoothen rough surfaces, improving aesthetics and functionality. Machining processes may be employed to achieve precise dimensional accuracy, especially for critical components [22].
Furthermore, thermal treatments like annealing or stress relieving can optimize the mechanical properties of printed parts, enhancing their strength, durability, and re-sistance to fatigue [23]. Chemical treatments, such as coatings or surface modification, can impart specific functionalities like corrosion resistance or biocompatibility [24]. The selection and sequence of post-processing steps are crucial and often tailored to the specific material, AM technology, and desired part characteristics. Effective post-processing not only elevates the overall quality of the parts but also ensures their functionality and reliability in real-world applications [25].
In this context, post-processing serves as a crucial connection between the AM process and the end-use application by refining the properties of printed parts, ensuring they meet stringent quality standards and functional requirements demanded by various industries [26]. Its strategic application significantly contributes to unlocking the potential of AM technologies in producing high-quality, functional components.
The article seeks to highlight the critical role that post-processing methods play in refining and perfecting components produced through additive manufacturing. It begins by contextualizing the significance of additive manufacturing across industries, emphasizing the necessity of post-processing to overcome inherent limitations and achieve superior part quality. The complexities of AM processes are discussed, highlighting the challenges faced in producing high-quality components directly from the process and asserting the pivotal role of post-processing in addressing these challenges. It delves into the multifaceted nature of post-processing, discussing how techniques such as thermal, chemical, and mechanical treatments contribute to refining surface finish, enhancing mechanical properties, and ensuring dimensional accuracy.

2. The Categories of Post-Processing in AM

Selective laser sintering (SLS) is a revolutionary 3D printing method that utilizes a laser to selectively fuse powdered materials, typically polymers or metals and layer by layer, to create intricate and complex three dimensional objects. In the SLS process, a thin layer of powdered material is evenly spread across the build platform and a high powered laser selectively sinters or melts the powder based on the digital design data. This allows for the creation of intricate and precise structures with a high degree of complexity. One of the notable advantages of SLS 3D printing is its ability to produce functional prototypes and end use parts without the need for support structures, as the unsintered powder surrounding the printed object acts as a natural support during the printing process. This technology finds applications in various industries, including aerospace and automotive and medical, due to its versatility and capability to produce durable and detailed components [26].
Stereolithography (SLA) is a 3D printing method that employs a liquid resin that is cured, layer by layer, using an ultraviolet (UV) laser or light source. The SLA process begins with a vat of liquid resin and as the UV laser traces the cross section of the object to be printed, it solidifies the resin, thus, creating a layer. The build platform then descends and the process repeats until the entire object is formed. SLA 3D printing is known for its high resolution and its ability to produce detailed, smooth, and aaccurate prototypes and end use parts. It is commonly used in applications requiring fine features, such as jewelry, dental models and intricate prototypes [27].
Fused deposition modeling (FDM), on the other hand, is a widely adopted 3D printing technique that builds objects layer by layer using thermoplastic filaments. In FDM, a heated nozzle extrudes the filament onto a build platform, creating the desired shape. The material cools and solidifies quickly, allowing for the construction of three dimensional objects. FDM is known for its simplicity, cost effectiveness, and versatility. It is commonly used in various industries for rapid prototyping, producing functional parts and creating large scale objects. While FDM may not achieve the same level of precision as SLA, it excels in durability and is suitable for a broad range of applications, making it a popular choice in the 3D printing landscape [28].
Post-processing in AM serves as a critical phase, essential for refining and optimiz-ing the physical and mechanical properties of printed components. The inherent charac-teristics of AM processes often result in surface irregularities, compromised dimensional accuracy, and varied mechanical properties within the manufactured parts [28]. Consequently, post-processing techniques play a fundamental role in rectifying these shortcomings to attain the requisite standards for functional deployment in diverse industries.
Surface refinement represents a pivotal objective in post-processing, addressing the surface roughness and irregularities prevalent in AM-fabricated components. Techniques such as polishing, abrasive finishing, or chemical treatments are instrumental in achieving the desired surface quality necessary for aerodynamic efficiency in aerospace applications or biocompatibility in medical contexts [29]. Moreover, post-processing interventions facilitate precise dimensional accuracy, mitigating inherent distortions or deviations in the printed parts. Processes like precision machining or laser trimming are instrumental in refining the dimensional attributes of components, ensuring compliance with specified tolerances and seamless integration within larger assemblies [30].
Another critical aspect pertains to the optimization of mechanical properties. AM-fabricated parts might exhibit inconsistencies in material integrity and mechanical strength [31]. Post-processing treatments such as heat treatment, stress relieving, or surface coatings play a pivotal role in enhancing the mechanical attributes of components, improving their structural integrity, durability, and resistance to fatigue [32,33]. Additionally, tailored post-processing steps address material-specific challenges encountered in different additive manufacturing processes, such as porosity in metal AM, optimizing material homogeneity and performance [34].
The functional demands of various industries also necessitate specific properties in AM-produced components. Post-processing interventions, such as surface treatments, coatings, or annealing, are instrumental in conferring these functional characteristics, ensuring compliance with industry-specific requirements for corrosion resistance, electrical conductivity, or biocompatibility [35,36]. Moreover, the stringent regulatory standards prevalent in sectors like healthcare and aerospace necessitate meticulous adherence, a feat accomplished through thorough post-processing to ensure final parts meet these stand-ards for safety, quality, and performance [37,38].
Post-processing stands as a critical phase in AM, exerting a profound influence on the mechanical properties, aesthetics, and overall performance of AM-fabricated parts. The inherent nature of AM often yields components with varied surface finishes, imperfect layer adhesion, and inconsistent material properties, necessitating post-processing interventions to rectify these limitations and optimize the functionality of the final product [39].
Mechanical properties represent a focal point influenced by post-processing. AM manufactured parts might exhibit altered mechanical characteristics owing to factors like printing orientation, layer-by-layer construction, and material inconsistencies. Post-processing treatments such as heat treatment, stress relieving, or surface coatings significantly impact the mechanical attributes of these components [40]. Heat treatment processes, for instance, can refine the microstructure of materials, enhancing their strength, hardness, and overall mechanical performance. Moreover, stress relieving reduces residual stresses within printed parts, mitigating the risk of failure under mechanical loads [41]. Additionally, surface coatings or reinforcement techniques applied during post-processing contribute to augmenting specific mechanical properties, such as wear resistance or tensile strength, tailored to the demands of diverse applications [42].
Aesthetics constitute another facet profoundly impacted by post-processing in AM. The surface finish of additively manufactured parts often exhibits visible layer lines, ir-regularities, or roughness, detracting from both visual appeal and functional performance. Post-processing techniques, ranging from mechanical polishing to chemical smoothing, play a pivotal role in refining the surface quality of these components. Mechanical polishing methods meticulously remove surface imperfections, resulting in a smoother texture and improved aesthetics [42]. Chemical treatments involving solvent baths or reactive agents work toward dissolving or smoothing the surface, creating visually appealing, uniform surfaces. These interventions not only enhance the overall appearance but also contribute to functional aspects, ensuring reduced friction, improved material properties, and increased durability [43].
The combined impact of refined mechanical properties and enhanced aesthetics achieved through post-processing techniques culminates in improved overall performance [44,45]. Parts subjected to meticulous post-processing exhibit superior mechanical integrity, dimensional accuracy, and surface quality, translating into heightened functionality and reliability across diverse applications. Whether in aerospace, automotive, medical, or consumer goods industries, the comprehensive impact of post-processing on mechanical properties, aesthetics, and performance underpins its indispensable role in achieving the desired standards for additively manufactured parts [46]. Table 1 depicts the detailed aspects of post-processing techniques in additive manufacturing.

3. Common Post-Processing Techniques

In AM, post-processing techniques serve as indispensable steps in refining the quality, functionality, and usability of printed components. Among the array of methodologies employed, several stand as cornerstones in achieving the desired outcomes. Cleaning, an initial and crucial step, involves the removal of residual powders support structures or contaminants adhering to the printed parts [47]. Techniques vary from simple manual brushing or air blowing to more intricate processes like solvent baths or ultrasonic cleaning, ensuring the elimination of debris while preserving part integrity.
Surface finishing techniques encompass an array of procedures aimed at refining the surface texture and appearance of AM-fabricated components [48]. Mechanical methods, including sanding, grinding, or abrasive blasting, are effective in reducing surface roughness and eliminating visible layer lines. Also, heat treatment can be considered as a post-processing technique, where through controlled heating and cooling cycles, microstructure is optimized, internal stresses are relieved and mechanical properties like hardness, strength and ductility are enhanced [49]. In addition, support structure removal, especially prevalent in powder-based or resin-based AM processes, is an essential post-processing step involving the careful removal of temporary supports used during the printing process to maintain the integrity of overhanging or intricate features [50]. Moreover, surface coating in AM revolutionizes 3D-printed components by applying protective or functional coatings to enhance properties like wear resistance or conductivity [51]. Also, hot isostatic pressing (HIP) is a post-processing technique that subjects a material to high temperature and pressure in a gas environment, effectively consolidating, and eliminating porosity in additive manufacturing components [52]. What is more, electropolishing, prevalent in metal-based AM, enhances metallic part surfaces by electrolytically removing outer layer imperfections, boosting corrosion resistance, and elevating aesthetics, vital for aerospace, automotive, and medical applications [53]. At last, ultrasonic finishing uses ultrasonic vibrations to precisely polish AM-fabricated surfaces [54]. This process reduces imperfections and ensures high-quality finishes across intricate geometries, catering to various industry needs.
Each of these post-processing techniques plays a distinct yet interrelated role in re-fining the quality, functionality, and usability of AM-fabricated parts. Their careful application ensures that additively manufactured components meet stringent standards for surface finish, dimensional accuracy, mechanical properties, and overall performance across various industries. Table 2 provides an overview of key post-processing techniques in additive manufacturing, their descriptions, and their respective applications in refining the quality, functionality, and usability of 3D-printed parts across various industries.

3.1. Cleaning

A crucial post-processing stage in additive manufacturing is cleaning, aiming to eliminate residual powders, support structures, or contaminants adhering to AM-fabricated parts [55]. The primary purpose is two-fold: to ensure the removal of debris for maintaining part integrity and to prepare the components for subsequent treatments or direct use within various industries.
Methodologies for cleaning span a spectrum, ranging from basic techniques like manual brushing, air blowing, or wiping, ideal for the removal of loose powders or support materials. Advanced approaches encompass solvent baths, ultrasonic cleaning, or precision water jetting, particularly effective in eliminating residues from intricate geometries or convoluted internal structures. Figure 1 depicts the cleaning/removal process of water soluble supports on a FDM 3D-printed part.
In our literature review on post-production cleaning processes in additive manufacturing, we systematically evaluated the efficiency of various cleaning methodologies [55]. Quantitative assessments revealed that precision water jetting demonstrated exceptional efficacy in removing residual powders and support structures from intricately designed 3D-printed components achieving an average debris removal rate of 98%. This superior performance makes precision water jetting particularly advantageous for eliminating residues from convoluted internal structures as showcased in Figure 1. Conversely basic techniques such as manual brushing and air blowing exhibited lower but still significant removal rates and averaging around 85%, making them suitable for simpler geometries and loose powder removal. Solvent baths and ultrasonic cleaning demonstrated intermediate effectiveness with removal rates ranging from 90% to 95% providing versatility for a broad spectrum of 3D-printed structures.
However, our review uncovered challenges associated with potential damage during the cleaning process. Delicate or complex features within printed parts exhibited susceptibility to distortion with a measured distortion rate of 2.5% on average across various cleaning methods [56]. Careful handling emerged as imperative to prevent alterations to intricate structures. Furthermore, meticulous cleaning was essential to avoid compromising part integrity or surface finish. Achieving a delicate balance between effective debris removal and preservation of the structural and aesthetic integrity of 3D-printed components remains a paramount focus in optimizing post-processing techniques within additive manufacturing. These findings underscore the importance of not only choosing appropriate cleaning methodologies based on geometric complexity but also implementing careful handling protocols to mitigate the risk of damage during the cleaning process.

3.2. Surface Finishing

Surface finishing techniques in additive manufacturing serve a crucial purpose: refining surface texture, eradicating visible layer lines, and enhancing both the aesthetic appeal and functional properties of printed components [57]. Methodologies employed encompass both mechanical and chemical techniques. Mechanical methods like sanding, grinding, or abrasive blasting physically remove surface imperfections and layer lines. Conversely, chemical treatments such as solvent smoothing or vapor polishing selectively dissolve or melt outer layers, resulting in smoother surfaces. Additionally, methods like media tumbling or electrochemical processes are utilized to achieve specific surface textures [57]. Figure 2 depicts two separate FDM 3D printed parts upon being processed with the vapor polishing technique, which has drastically improved its aesthetical surface finish. This method involves exposing the printed part to vaporized solvents, such as acetone for ABS (Acrylonitrile Butadiene Styrene) or IPA (Isopropyl Alcohol), for certain types of resin-based prints, in a controlled environment. The process begins by heating the solvent to create a vapor, which generates a mist that envelops the printed object. As the vapor interacts with the surface of the part, it selectively liquefies and melts the outer layer of the thermoplastic material. This action leads to the smoothing of layer lines and imperfections, resulting in a more uniform and polished surface finish.
In our comprehensive analysis of surface finishing techniques within additive manufacturing we systematically evaluated the impact of various methods on surface texture and layer line visibility and the overall properties of 3D-printed components. Mechanical techniques, including sanding, grinding, and abrasive blasting, exhibited a remarkable efficiency in reducing layer lines, significantly enhancing both the visual and functional qualities of printed parts. Quantitative assessments further revealed a high degree of improvement in surface roughness values after mechanical treatments underscoring their efficacy in refining surface texture [57].
Concurrently, chemical treatments such as solvent smoothing and vapor polishing were scrutinized for their influence on material properties. The vapor polishing technique when applied to FDM 3D-printed parts demonstrated a visible reduction in layer lines and a high degree of improvement in surface smoothness compared to untreated counterparts. Notably, the controlled exposure to vaporized solvents such as acetone for ABS or IPA for resin-based prints showcased minimal impact on material integrity with mechanical property tests indicating no significant deviation from baseline values [57]. This quantitative insight establishes the viability of vapor polishing in achieving superior surface finishes without compromising the structural integrity of 3D-printed components.
However, challenges persist in achieving uniform surface finishes across complex geometries. Our review revealed a slight decrease in the effectiveness of mechanical methods and in the efficiency of vapor polishing when applied to intricate convoluted structures. Furthermore, a risk of overpolishing or inadvertently damaging delicate features during these procedures remains, emphasizing the need for precision and further optimization in surface finishing methodologies within additive manufacturing [58].

3.3. Heat Treatment

Heat treatment stands as a foundational post-processing technique integral to optimizing the performance and properties of 3D-printed parts within additive manufacturing [59]. The primary objective of heat treatment lies in the meticulous optimization of the material’s microstructure and a process crucial for enhancing mechanical properties such as hardness, strength and ductility in 3D-printed components. Through controlled heating and subsequent cooling cycles, heat treatment methodologies like annealing and tempering or stress relieving are employed to induce specific alterations in material properties [60].
In a comprehensive examination of the impact of heat treatment on metal based 3D-printed components our study revealed compelling insights. Annealing, a common heat treatment process demonstrated a substantial refinement in grain structures and leading to an increase in hardness and a notable improvement in tensile strength compared to untreated counterparts [59]. Additionally and stress relieving contributed to a remarkable 15% reduction in residual stresses and enhancing the overall durability of the final part. However, achieving these enhancements required meticulous temperature control throughout the treatment process to avoid material distortion or warping and ensuring the structural integrity of the component. Furthermore, there was a small risk of potential chandes in dimensional accuracy and emphasizing the need for meticulous control and adherence to specified parameters during heat treatment [61]. This quantitative data not only validates the efficacy of heat treatment but also highlights the critical importance of precise control to achieve desired material characteristics while maintaining dimensional precision.
Moreover, our investigation unveiled potential challenges associated with the emergence of new defects within the material during the heat treatment process. Detailed monitoring and control were essential to mitigate such occurrences with literature data indicating a very slight incidence of new defects when proper control measures were not strictly adhered to [61]. Addressing these challenges is paramount in unlocking the complete efficacy of heat treatment within additive manufacturing. The pivotal objective lies in achieving an equilibrium between attaining specified material characteristics while upholding dimensional precision—a focal point pivotal to the enhancement of heat treatment methodologies for additively manufactured components. The continual progression and meticulous refinement of techniques in this field serve as indispensable facets in guaranteeing the uniformity and heightened quality of the final output and thereby bolstering the dependability and adaptability of additive manufacturing across multifarious industrial domains. Figure 3 depicts 3D-printed parts during the annealing process [60].

3.4. Support Structures Removal

The elimination of support structures is an essential post-processing operation, focusing on eliminating temporary supports used during the printing process to uphold the integrity of intricate or overhanging features in the final AM-fabricated part [62]. Support removal methodologies encompass a diverse spectrum of techniques tailored to specific materials and printing processes employed. From manual removal utilizing tools like pliers or cutters to automated processes like water jetting, mechanical agitation, or chemical dissolution, each method is adapted to suit the unique characteristics of the printed material and the printing technology utilized [62].
Nevertheless, the procedures of support withdrawal are accompanied by a number of shortcomings. Delicate or intricate features within the printed part are susceptible to damage during support removal, emphasizing the need for careful handling to preserve these crucial elements [63]. Ensuring the complete removal of supports without leaving residues presents another challenge, demanding meticulous attention to detail to avoid any remnants that could compromise the part’s integrity or functionality. Striking a balance between effective support removal and the preservation of part integrity remains a crucial consideration in this post-processing step.
The synthesis of findings from relevant literature review illuminates key insights into the efficacy of various support structure removal methodologies. Through quantitative assessments it was discerned that precision water jetting as a method for support removal and consistently achieved high efficiency in eliminating residual supports and surpassing alternative techniques [63]. Additionally, surface roughness measurements indicated a noteworthy reduction, with post-processing precision water jetting suggesting a significant enhancement in the aesthetic properties of 3D-printed components [62]. In contrast, manual removal using tools like pliers or cutters and automated processes such as water jetting and mechanical agitation exhibited commendable removal rates making them particularly suitable for less intricate geometries. Further analysis of surface roughness demonstrated a slight reduction with these fundamental support removal techniques and providing valuable context on their performance [63].
However, the literature review also shed light on challenges associated with support removal and particularly the risk of damaging delicate features. Analyses of intricate structures disclosed a very low incidence of distortion or alteration when subjected to precision water jetting and highlighting the crucial need for careful handling to preserve the structural integrity of 3D-printed components [63]. Moreover and maintaining a delicate balance between effective support removal and the preservation of aesthetic and structural integrity emerged as a key focus. Notably, a very small compromise in structural integrity was identified when employing precision water jetting on complex geometries [62]. These findings and derived from a comprehensive examination of existing literature and provide essential insights guiding future research endeavors and contributing to the optimization of support structure removal techniques in additive manufacturing processes. Figure 4 depicts the manual support removal on a 3D-printed part by the end-user.

3.5. Surface Coating

Surface coating serves as a pivotal post-processing technique within additive manufacturing, focusing on the application of protective or functional coatings to augment specific properties such as wear resistance, corrosion resistance, or conductivity in printed components [64,65]. The methodologies employed in surface coating encompass a diverse array of techniques tailored to meet distinct application needs [66]. Each method deposits thin layers of materials onto the surface, inducing alterations in properties without compromising the integrity of the underlying bulk material. Figure 5 depicts a 3D printed part during surface coating application.
The synthesis of findings from literature review sheds light on the process of surface coating as a critical post-processing technique within additive manufacturing. Various coating types such as polymer coatings, metal coatings, and ceramic coatings have been identified, each tailored to address specific application requirements and enhance distinct properties in 3D-printed components [64,65]. Notably, studies have reported that polymer coatings contribute to improved wear resistance while metal coatings exhibit enhanced conductivity. These diverse coatings are applied through techniques like chemical vapor deposition and electroplating or dip coating, each imparting unique attributes to the printed materials [66].
Despite the promising benefits and challenges identified, literature underscores the importance of meticulous implementation. It is revealed that achieving a uniform coating thickness remains a persistent challenge and demanding precise control measures during the coating process [67]. Studies emphasize the significance of innovative solutions to ensure consistent adhesion and particularly in intricate geometries to optimize the functional properties of the coated components. Additionally, investigations highlight the critical role of controlling coating parameters and understanding material characteristics to prevent defects such as cracks or uneven coverage.
The strategic resolution of these challenges as indicated by literature findings is fundamental in advancing surface coating methodologies within additive manufacturing. Research underscores the necessity for precision and tailored approaches to establish standardized and high-quality coating processes. These endeavors not only elevate the functional attributes and durability of additively manufactured components but also contribute to the ongoing advancements in coating technologies. The literature indicates a promising trajectory toward solutions characterized by increased reliability and adaptability across diverse industrial sectors, enhancing the overall effectiveness of additive manufacturing and expanding its scope of application.

3.6. Electropolishing

Electropolishing represents a significant post-processing technique, particularly for metal parts within additive manufacturing, aimed at refining surface finish, eliminating imperfections, and augmenting corrosion resistance [68]. The methodology of electropolishing involves immersing the 3D-printed part in an electrolyte solution while applying an electrical current. This controlled electrochemical process effectively smooths surface irregularities and creates a sleek, lustrous finish that levels out microscopic peaks and valleys [69]. This controlled dissolution creates a uniform surface, refining the part’s geometry without altering its overall dimensions or intricate details. Moreover, electropolishing facilitates the removal of surface contaminants and residual stresses that may compromise the mechanical properties of 3D-printed components. By minimizing stress concentrations and microcracks, it can enhance the fatigue resistance and mechanical strength of the parts.
Electropolishing is versatile and applicable to various materials commonly used in additive manufacturing, including stainless steel, titanium, and certain alloys. Its adaptability across multiple material types further accentuates its significance as a post-processing technique in 3D printing [69]. Figure 6 depicts metal 3D-printed parts during electropolishing process [70] and is included in this article under license from GPAINNOVA DLyte®, Barcelona, Spain.
However, several challenges are inherent to the electropolishing process. Ensuring uniformity in the treatment across the entire surface area of the part remains crucial, demanding precise control and monitoring throughout the process. Controlling the dissolution rate is another challenge, as variations can impact the final surface quality [71]. Additionally, meticulous monitoring is essential to prevent excessive material removal, which could compromise dimensional accuracy or structural integrity if not carefully managed [71].
Efficiently managing these challenges holds paramount importance in the optimization of electropolishing techniques within the additive manufacturing landscape. The refinement of process control mechanisms, integration of cutting-edge monitoring technologies, and the implementation of precision-based methodologies are pivotal in attaining uniform and superior surface finishes across a spectrum of metallic parts. Sustained enhancements in this field will further bolster the efficacy of electropolishing, facilitating augmented surface properties and prolonged durability in the realm of metal-based additive manufacturing applications.
Recent literature findings provide additional concrete data to underscore the practical application and efficacy of this post-processing technique. Notably, studies have demonstrated that electropolishing achieves an average surface roughness reduction of 30% showcasing its prowess in significantly enhancing both the visual and mechanical characteristics of 3D-printed metal components [68,69]. This specific data corroborates the methodology’s ability to level microscopic irregularities resulting in a sleek and lustrous finish that refines the geometry of printed parts without compromising their overall dimensions or intricate details. Furthermore, investigations reveal a substantial increase in corrosion resistance for electropolished stainless steel parts compared to their untreated counterparts [70]. This empirical evidence underscores the tandible benefits of electropolishing in augmenting the durability and longevity of metal based additively manufactured components.
However, the literature also acknowledges inherent challenges in the electropolishing process. Maintaining uniformity in treatment across the entire surface area of a part is identified as crucial, necessitating precise control and continuous monitoring throughout the process. Controlling the dissolution rate presents another challenge, as variations can impact the final surface quality. The literature review findings emphasize that meticulous monitoring is essential to prevent excessive material removal, which, if not carefully managed, could compromise dimensional accuracy or structural integrity [71].
The integration of these specific findings not only enriches the understanding of the practical application of electropolishing but also highlights its potential in addressing specific performance criteria such as surface roughness reduction and enhanced corrosion resistance. The ongoing refinement of process control mechanisms, incorporation of cutting edge monitoring technologies and implementation of precision based methodologies are identified as pivotal in leveraging the potential of electropolishing for achieving uniform and superior surface finishes across a spectrum of metallic parts. As the literature continues to evolve, these advancements promise to further bolster the efficacy of electropolishing and solidifying its role as a valuable post-processing technique in the domain of metal based additive manufacturing applications.

3.7. Ultrasonic Finishing

Ultrasonic finishing stands as a specialized post-processing technique within additive manufacturing, leveraging ultrasonic vibrations to refine and polish the surfaces of AM-fabricated parts [72]. The methodology of ultrasonic finishing involves the agitation of a mixture comprising abrasive particles and liquid using ultrasonic vibrations. This controlled agitation facilitates the precise removal of surface imperfections, resulting in a refined and improved surface finish. The technique’s principle lies in the mechanical energy transferred to the printed part’s surface through abrasive particles suspended in a liquid medium [72]. As ultrasonic energy agitates the slurry, the abrasive particles effectively abrade the surface, gradually eroding imperfections and irregularities, resulting in a finer and smoother texture.
Ultrasonic finishing presents several advantages in post-processing AM-fabricated parts [73]. One key benefit is its ability to access complex geometries and intricate details that are challenging to reach through traditional finishing methods. The non-directional nature of ultrasonic vibrations ensures uniform treatment across various surface contours, ensuring consistent finishing quality [73]. Moreover, this technique minimizes material removal, preserving the dimensional accuracy and intricacies of the original print. It also mitigates the risk of damaging delicate features, making it particularly suitable for parts with intricate designs or thin walls. The process’s efficiency and relatively low energy consumption contribute to its eco-friendly profile, aligning with the contemporary emphasis on sustainable manufacturing practices. Figure 7 depicts 3D-printed parts during the ultrasonic finishing process.
However, challenges are inherent in the ultrasonic finishing process. Controlling the distribution of abrasive particles across the surface proves crucial, demanding meticulous management to ensure uniformity and prevent irregularities. Achieving consistent surface finish across varied geometries presents another challenge, requiring tailored approaches to address the complexities of different part configurations. Moreover, the potential for inadvertent damage to delicate features during the ultrasonic process underscores the need for careful handling and precision control [74].
Effectively managing these challenges is vital in optimizing ultrasonic finishing techniques within additive manufacturing. Advancements in control mechanisms, innovative methodologies, and precision technologies will play pivotal roles in achieving consistent and high-quality surface finishes across diverse AM-fabricated parts. Continuous refinements in this domain will fortify the efficacy and applicability of ultrasonic finishing, offering refined, visually appealing, and functionally superior end-products.

3.8. Hot Isostatic Pressing (HIP)

Hot isostatic pressing (HIP) stands as an important post-processing technique in additive manufacturing, particularly for enhancing the properties of metal based components. In this method, components such as metal 3D-printed parts undergo simultaneous exposure to elevated temperatures and high pressure gas, effectively addressing inherent porosity and voids within the material thereby optimizing its density and enhancing structural integrity [75]. The significance of HIP lies in its capability to rectify the prevalent challenge of porosity in metal additive manufacturing. The presence of voids and air pockets within the material poses a threat to the mechanical properties and structural soundness of the final product [76]. Literature review findings indicate that HIP methods successfully mitigate these issues and resulting in components with improved density, reduced defects and superior mechanical characteristics.
HIP’s applications span various industries including aerospace, automotive, medical, and energy sectors. The aerospace industry relies on HIP methods to ensure the integrity of critical components in aircraft engines, emphasizing the paramount importance of structural reliability. In the medical field, HIP techniques play a crucial role in producing high-quality implants with enhanced biocompatibility and improved mechanical behavior. The versatility of HIP methods in accommodating various metal based materials including alloys and superalloys makes it a preferred choice across diverse industries where stringent material requirements are imperative [77].
Nevertheless, HIP methods present certain limitations, including the associated costs of specialized equipment and the energy intensive nature of the process which can be constraining factors especially for industries with budget constraints. Additionally, the time consuming nature of the process and potential size restrictions on components undergoing HIP procedures may impact overall production timelines and scalability [78].
Recent literature findings provide specific data reinforcing the efficiency of HIP. Studies reveal a substantial improvement in fatigue resistance and tensile strength for components subjected to HIP compared to conventionally processed counterparts [79]. These empirical observations underscore the tandible benefits of HIP in elevating the quality and reliability of metal based additive manufacturing components, derived from systematic reviews and analyses within the academic and industrial research landscape.
Figure 8 offers a schematic representation of the HIP method, providing a visual insight into the process and facilitating a comprehensive understanding [80]. Despite acknowledged limitations, it is evident that HIP remains a powerful tool in ensuring the quality and reliability of metal based additive manufacturing components with specific data supporting its positive impact on crucial mechanical properties gleaned from contemporary literature reviews and research studies.

4. Challenges and Limitations of Post-Processing Techniques

Post-processing in AM introduces a number of challenges and limitations that im-pede seamless integration and pose significant considerations in achieving optimal out-comes. These challenges span various facets, encompassing aspects of consistency, labor intensity, and cost, profoundly impacting the efficiency, reliability, and scalability of post-processing operations [79]. Figure 9 depicts such prominent aforementioned challenges.
Achieving consistent results across different geometries, materials, and post-processing techniques remains a notable challenge in AM. Variations in part geometry, size, and complexity necessitate tailored post-processing approaches, making standardization challenging. Ensuring uniform surface finishes, mechanical properties or dimensional accuracy across a batch of printed parts demands meticulous control over processing parameters, often requiring iterative adjustments and specialized expertise [81].
Also, post-processing in AM frequently involves labor-intensive processes, ranging from manual support removal to intricate surface treatments [82]. Labor-intensive tech-niques like manual polishing, support removal, or precise finishing require skilled operators, consuming time and resources. The human intervention necessary for these tasks increases the potential for variability in outcomes, impacting repeatability and scalability [83].
In addition, the costs associated with post-processing in AM pose a significant con-cern. Labor-intensive processes, specialized equipment, consumables, and expertise contribute to escalated operational expenses [84]. Furthermore, the need for specialized facilities, such as controlled environments for certain treatments or high-tech equipment for precise surface modifications, adds to the overall cost, making post-processing a substantial economic factor in the additive manufacturing workflow [85].
Furthermore, different materials used in AM exhibit unique post-processing chal-lenges [86]. For instance, metal AM parts may require complex heat treatment cycles to optimize mechanical properties, while polymers might demand specific chemical treat-ments or vapor smoothing techniques. Adapting post-processing techniques to suit di-verse materials necessitates a nuanced understanding of material behaviors and their re-sponse to various treatments, adding complexity and potential variability to the process [87].
Similarly, scaling up post-processing operations to meet industrial production de-mands presents a significant challenge. The transition from small-scale prototyping to large-scale production often requires streamlining post-processing methods for increased throughput without compromising quality [88]. Integrating post-processing seamlessly within the AM workflow, minimizing process interruptions, and optimizing overall production timelines remains a challenge yet crucial for efficient manufacturing.
Moreover, labor-intensive post-processing tasks, necessitating meticulous manual labor for support removal or intricate surface refinement, inherently prolong the manufacturing cycle [89]. Such tasks demand time-intensive efforts that can lead to delays and hinder throughput. The variability in post-processing requirements among diverse parts further complicates scheduling and may introduce bottlenecks within the production workflow, curtailing the overall speed and efficiency of manufacturing operations.
Lastly, inefficiencies or inconsistencies within post-processing methodologies pose a threat to the seamless flow of the manufacturing workflow. Interruptions stemming from inconsistencies or bottlenecks in post-processing can significantly disrupt the overall op-erational efficiency of AM, potentially causing production delays and affecting the productivity of the entire manufacturing system [90].
Efforts aimed at mitigating these challenges necessitate streamlined post-processing methods, increased automation, standardized procedures, and continuous innovation in materials and technologies. Achieving a harmonious balance between consistent quality, cost-effectiveness, and scalability in post-processing remains pivotal to unlock the potential of additive manufacturing in realizing efficient and sustainable large-scale production processes across various industries.

5. Innovations in Post-Processing Techniques

Recent advancements in post-processing techniques within AM have heralded a transformative era, aiding the refinement and optimization of AM-fabricated compo-nents. Innovations across various facets of post-processing, encompassing surface finish-ing, heat treatment methodologies, materials development, and equipment integration, have contributed to evolution of additive manufacturing, promising enhanced efficiency, precision, and functionality in the final parts.
Advanced surface finishing techniques have emerged, offering unprecedented control and precision in refining surface qualities. Tailored chemical polishing solutions, designed to suit diverse materials and geometries, boast exceptional effectiveness in reducing surface roughness and eradicating visible layer lines. Automated robotic polishing systems, equipped with adaptive controls, ensure uniformity in surface finishes across in-tricate part designs, effectively reducing labor-intensive processes while ensuring conistent quality.
In the field of heat treatment, innovative strategies such as gradient annealing and localized heat treatments using laser systems have enabled precise manipulation of mate-rial microstructures [91]. These techniques yield superior mechanical properties, endow-ing AM parts with heightened strength and durability, expanding their application scope in demanding industries [92].
Materials innovation has driven the development of post-processing-specific materi-als, engineered to tackle specific challenges encountered in AM. Tailored abrasive media, specialized surface coatings [93], and environmentally friendly support materials cater to efficient post-processing operations while minimizing waste generation, enhancing compatibility across various AM technologies [94].
The integration of advanced equipment and automation marks a pivotal shift in post-processing workflows. Robotic systems, empowered by artificial intelligence algorithms, facilitate autonomous decision-making, optimizing parameters for consistent and precise outcomes [95,96]. Simultaneously, in-line inspection and quality control systems embedded within post-processing equipment ensure real-time monitoring, enabling immediate corrective actions and minimizing defects, ultimately optimizing overall process efficiency [97,98]. Data-driven insights derived from past processes and outcomes enable predictive analytics, empowering operators to optimize process parameters for maximum efficiency and quality. This proactive approach empowers operators to take prompt corrective actions, ensuring adherence to quality standards and minimizing the production of substandard parts. This has been instrumental in addressing persistent challenges and elevating the quality standards of post-processed parts. These technologies are strategi-cally engineered to tackle inherent complexities, enhance precision, and optimize efficiency, thereby mitigating challenges and ensuring superior quality outcomes.
In addition, technologies integrating post-processing seamlessly within the additive manufacturing workflow are becoming increasingly prevalent [99]. Integration at various stages, from design to final part finishing, streamlines operations, reducing disruptions, and enhancing overall efficiency [100]. This holistic approach ensures that post-processing considerations are factored in during the entire manufacturing cycle, optimizing quality from start to finish.
These recent advancements signify a convergence of state-of-the-art technologies with the objective of surmounting challenges and augmenting the quality standards in post-processed components. The ongoing evolution and amalgamation of these technolo-gies emphasize a promising trajectory, enabling additive manufacturing to attain un-precedented levels of efficiency, precision, and quality within various industrial sectors. Table 3 encapsulates the diverse advancements in post-processing techniques within additive manufacturing.

6. Future Directions and Research Opportunities

As AM processes constantly evolve, the field of post-processing processes undergoes a subsequent significant transformation characterized by promising new technologies. These advancements stand poised to reconfigure the function, efficacy and capacities of post-processing and enhancing its pivotal role in optimizing and expanding the capabilities of AM technologies within a multitude of industrial sectors. An imerging tendency involves the integration of post-processing steps directly within the additive manufacturing workflow [101]. In line and in situ post-processing techniques embedded within the AM machines or production cells aim to streamline processes, minimize interruptions, and optimize part quality [102]. This integration ensures seamless transitions from printing to post-processing stages, reducing lead times and enhancing overall process efficiency.
Moreover, the future of post-processing in AM is deeply intertwined with advance ments in automation and robotics. The rise of autonomous systems equipped with AI driven algorithms and advanced sensors promises precision driven, standardized post-processing operations [103]. The increased adoption of robotics in tasks such as support removal, surface finishing, and quality inspection aims to reduce labor intensity, improve repeatability while ensuring consistent quality across batches of printed components [104].
Also, the advent of smart post-processing techniques incorporates adaptive control mechanisms and real time monitoring systems [105]. These innovations enable post-processing equipment to adjust parameters based on the unique characteristics of each printed part, optimizing process parameters and ensuring tailored treatments for specific geometries and materials [105]. Smart systems continuously learn and adapt, offering personalized and optimized solutions for diverse post-processing needs. Future developments in post-processing will witness an emphasis on materials innovation [106] and focusing on specialized post-processing specific materials. Tailored abrasive media, eco friendly support materials and advanced surface coatings will cater to specific post-processing challenges, ensuring enhanced compatibility, improved surface finishes and reduced environmental impact. Also, future directions in post-processing will prioritize sustainable practices and environmentally conscious solutions [107].
On the other hand, while automation in post-processing has immense contribution, there is room for improvement in developing more sophisticated and adaptable robotic systems [108,109]. Research efforts should aim at creating autonomous systems capable of handling intricate geometries, diverse materials and multi-step post-processing operations [109]. Integration of AI driven algorithms for adaptive control and real time decision making will enhance the precision and versatility of automated post-processing [110].
Also, advancements in real time monitoring and control systems during post-processing stages are imperative [111]. Research should focus on developing advanced sensors and in line inspection techniques to enable continuous monitoring of critical parameters. Even though there are published literature cases where real time monitoring is achieved [111], such efforts should not only solely focus on detecting defects but also provide actionable insights to adjust process parameters in real time, ensuring consistent quality and reducing the likelihood of errors. In this context, the integration of advanced optimization algorithms and predictive analytics can further assist post-processing. Continued research is needed to refine these algorithms further and enabling predictive models that optimize process parameters based on historical data and real time feedback.
In the same spirit, tailored materials for specific post-processing applications remain an area for further exploration [112]. Research into developing specialized abrasives, coatings, solvents, and support materials that are more effective and eco friendly and compatible with a wide rande of AM materials and geometries is essential. Novel chemistry compositions and materials should address challenges in surface finishing, support removal and other post-processing steps while minimizing environmental impact.
Another important issue is establishing standardized protocols and qualification methods for post-processed parts [113]. Further research should focus on developing industry wide standards for post-processing steps, ensuring consistency, reliability, and traceability across different AM technologies and materials. Qualification methods should verify the integrity, performance and durability of post-processed parts, paving the way for broader industrial adoption [113]. Continued research and development in these areas will advance the capabilities of post-processing in additive manufacturing, enabling more efficient, reliable and sustainable production of high-quality components across diverse industries.

7. Conclusions

In the dynamic and continually evolving field of additive manufacturing (AM), the optimization of post-processing methodologies emerges as a critical factor in fully realizing the potential inherent in AM fabricated components. Through exploration, significant findings underscore the transformative impact of refined post-processing techniques on structural integrity functional attributes and adaptability across various industries.
The integration of cutting edge technologies, automated systems, and material innovation within post-processing signals a new era focused on precision driven operational methodologies. Advances in surface finishing, heat treatments and tailored material solutions aim to enhance surface characteristics, mechanical attributes and overall performance of AM fabricated components. The convergence of AI facilitated automation, real time monitoring mechanisms and adaptive controls ensures standardized processes, reducing variations and enhancing uniformity across batches of printed elements. At the core of these advancements lies the pivotal role of optimized post-processing techniques in fostering efficiency, dependability, and eco conscious practices within the additive manufacturing framework.
The seamless integration of post-processing stages, coupled with predictive analytics for parameter optimization and the adoption of environmentally friendly material solutions, highlights a collective commitment to achieving outputs of elevated quality while minimizing ecological footprints. A key takeaway emphasizes the urgent need to prioritize and invest in continuous research and development in the greater sector of post-processing. Advancing automation, fine tuning material properties, establishing standardized protocols, and embracing sustainability initiatives collectively drive AM processes toward optimal efficiency and reliability.
In conclusion, the evolution and incorporation of post-processing methodologies serve as the linchpin in unlocking the latent potential of additive manufacturing and ensuring that AM fabricated components not only meet but surpass stringent quality benchmarks. As industries embrace AM technologies, the persistent refinement and amalgamation of optimized post-processing techniques will undoubtedly pave the way toward a future characterized by superlative and high performance components across a multifaceted spectrum of applications and sectors.

Author Contributions

Conceptualization, T.G., A.K. and F.I.T.P.; methodology, A.K.; validation, F.I.T.P., T.G., A.K., I.S.M. and L.M.U.; formal analysis, T.G., A.K. and F.I.T.P.; investigation, A.K. and F.I.T.P.; resources, A.K. and F.I.T.P.; writing—original A.K.; writing—review and editing, T.G., A.K., F.I.T.P., I.S.M. and L.M.U.; visualization, T.G. and A.K.; supervision, F.I.T.P., T.G. and A.K. All authors have read and agreed to the published version of the manuscript.

Funding

This research received no external funding.

Data Availability Statement

Data sharing is not applicable to this article.

Conflicts of Interest

The authors declare no conflicts of interest.

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Figure 1. Cleaning/removal process of water-soluble supports on a FDM 3D printed part.
Figure 1. Cleaning/removal process of water-soluble supports on a FDM 3D printed part.
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Figure 2. FDM 3D printed parts upon being processed with vapor polishing technique.
Figure 2. FDM 3D printed parts upon being processed with vapor polishing technique.
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Figure 3. 3D printed parts during the annealing process [60].
Figure 3. 3D printed parts during the annealing process [60].
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Figure 4. Manual support removal on a 3D printed part by the end-user.
Figure 4. Manual support removal on a 3D printed part by the end-user.
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Figure 5. 3D printed part during surface coating application.
Figure 5. 3D printed part during surface coating application.
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Figure 6. Metal 3D printed parts during the electropolishing process. (Figure provided under license from GPAINNOVA DLyte®).
Figure 6. Metal 3D printed parts during the electropolishing process. (Figure provided under license from GPAINNOVA DLyte®).
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Figure 7. 3D printed parts during the ultrasonic finishing process.
Figure 7. 3D printed parts during the ultrasonic finishing process.
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Figure 8. Schematic of hot isostatic pressing post-processing method, courtesy of the Metal Powder Industries Federation.
Figure 8. Schematic of hot isostatic pressing post-processing method, courtesy of the Metal Powder Industries Federation.
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Figure 9. Challenges and limitations of post-processing techniques in additive manufacturing.
Figure 9. Challenges and limitations of post-processing techniques in additive manufacturing.
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Table 1. Detailed aspects of post-processing techniques in additive manufacturing.
Table 1. Detailed aspects of post-processing techniques in additive manufacturing.
AspectPost-Processing Techniques
Surface RefinementPolishing, abrasive finishing, chemical treatments for improved aerodynamics, biocompatibility
Dimensional AccuracyPrecision machining, laser trimming for adherence to specified tolerances, and seamless integration
Mechanical PropertiesHeat treatment, stress relieving, surface coatings to enhance structural integrity, durability, and general mechanical behavior
Functional PropertiesSurface treatments, coatings, annealing for corrosion resistance, electrical conductivity, or biocompatibility
Regulatory StandardsThorough post-processing to meet stringent industry standards for safety, quality, and performance
AestheticsMechanical polishing, chemical smoothing for improved surface quality, reduced friction, and enhanced durability
Table 2. Post-processing techniques and corresponding materials in additive manufacturing.
Table 2. Post-processing techniques and corresponding materials in additive manufacturing.
Post-Processing TechniqueDescriptionApplicationMaterial
CleaningRemoval of residual powders, supports, or contaminants through methods like manual brushing or solvent bathsDebris elimination while preserving part integrityAll AM Materials
Surface FinishingMechanical methods (sanding, grinding) to reduce surface roughness and eliminate visible layer linesRefining surface texture and appearancePolymer-based AM Materials
Heat TreatmentControlled heating and cooling cycles to optimize microstructure, relieve internal stresses, and enhance mechanical propertiesImproving hardness, strength, and ductilityMetal-based AM Materials, Titanium Alloys
Support Structure RemovalCareful removal of temporary supports used in printing to maintain integrity of overhanging or intricate featuresEssential for powder-based or resin-based AM processesAll AM Materials
Surface CoatingApplication of protective or functional coatings to enhance properties like wear resistance or conductivityRevolutionizing properties of 3D-printed componentsPolymer-based AM Materials, Ceramic Materials
ElectropolishingElectrolytic removal of outer layer imperfections in metal-based AM, boosting corrosion resistance and aestheticsVital for aerospace, automotive, and medical applicationsStainless Steel, Metal Alloys
Ultrasonic FinishingUse of ultrasonic vibrations for precise polishing across intricate geometriesEnsuring high-quality finishes across various industry needsMetal-based AM Materials
Hot Isostatic Pressing (HIP)Subjects a material to high temperature and pressure in a gas environment, effectively consolidating and eliminating porosity in additive manufacturing componentsImproving structural integrity and material properties of metal-based components, reducing porosity, and ensuring superior performanceMetal-based AM Materials, Powder Metallurgy
Table 3. Diverse advancements in post-processing techniques within additive manufacturing.
Table 3. Diverse advancements in post-processing techniques within additive manufacturing.
Post-Processing FacetsAdvancements
Surface finishing- Tailored chemical polishing solutions
- Automated robotic polishing systems
- Control over surface roughness and layer lines reduction
Heat treatment- Gradient annealing
- Localized heat treatments using laser systems
- Enhanced mechanical properties in AM parts
Materials development- Tailored abrasive media
- Specialized surface coatings
- Environmentally friendly support materials
- Increased compatibility across AM technologies
Equipment integration- Robotic systems with AI algorithms
- In-line inspection and quality control systems
- Real-time monitoring for immediate corrective actions
- Predictive analytics for process optimization
Integration with AM- Seamless integration from design to finishing stages
- Reduction of disruptions, enhancing overall efficiency
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Kantaros, A.; Ganetsos, T.; Petrescu, F.I.T.; Ungureanu, L.M.; Munteanu, I.S. Post-Production Finishing Processes Utilized in 3D Printing Technologies. Processes 2024, 12, 595. https://doi.org/10.3390/pr12030595

AMA Style

Kantaros A, Ganetsos T, Petrescu FIT, Ungureanu LM, Munteanu IS. Post-Production Finishing Processes Utilized in 3D Printing Technologies. Processes. 2024; 12(3):595. https://doi.org/10.3390/pr12030595

Chicago/Turabian Style

Kantaros, Antreas, Theodore Ganetsos, Florian Ion Tiberiu Petrescu, Liviu Marian Ungureanu, and Iulian Sorin Munteanu. 2024. "Post-Production Finishing Processes Utilized in 3D Printing Technologies" Processes 12, no. 3: 595. https://doi.org/10.3390/pr12030595

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