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Micro/Nano Manufacturing

A special issue of Applied Sciences (ISSN 2076-3417). This special issue belongs to the section "Mechanical Engineering".

Deadline for manuscript submissions: closed (31 March 2019) | Viewed by 77036

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Special Issue Editors


E-Mail Website1 Website2
Guest Editor
Institute for Micro Integration (IFM), University of Stuttgart, Allmandring 9b, 70569 Stuttgart, Germany
Interests: microtechnology; micromanufacturing; nanomanufacturing; microsystems technology; system integration; electronic packaging; electronic assembly and interconnection technology; sensors; reliability
Special Issues, Collections and Topics in MDPI journals

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Guest Editor
Department of Mechanical Engineering, School of Engineering, University of Birmingham, Birmingham B15 2TT, UK
Interests: micromanufacturing; microreplication; micromachining; laser microprocessing; additive manufacturing; process chain design; functional surface patterning/texturing; process integration; technology maturity assessment
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Micro manufacturing is dealing with the fabrication of structures in the order of 0.1 to 1000 µm. The scope of nano manufacturing extends the size range of manufactured features to even smaller length scales below 100 nm. A sharp borderline between micro and nano manufacturing can hardly be drawn, such that both domains are treated as complementary within a closely interconnected scientific community. Both micro and nano manufacturing can be considered as important enablers for high-end products. Especially, such products are enabled by micro and nano features and structures to incorporate special optical, electronic, mechanical, fluidic or biological functions in existing and new emerging products and thus lead to unique selling points. Application fields include, but are not restricted to, metrology, industrial technology, automotive technology, medical technology, and life sciences. This Special Issue is dedicated to recent advances in research and development within the field of micro and nano manufacturing. Therefore, papers are welcome that report recent findings and advances in manufacturing technologies for producing products with micro and nano scale features and structures. Furthermore, papers that report applications underpinned by such advances in micro and nano manufacturing technologies are also welcomed. In particular, the Special Issue intends to cover, but is not limited to, the following topics:

  • Micro fabrication technologies, process chains and process characterisation;
  • Novel product designs, micro-assembly technologies and micro-handling;
  • Surface engineering and interface nanotechnology;
  • Process modelling and simulation;
  • Processing and characterisation of smart materials, multifunctional materials, nanomaterials and material related issues in micro and nano scale;
  • Micro and nano additive manufacturing technologies;
  • Micro and desktop factory concepts, systems, components and modules;
  • On-line monitoring and inspection systems/methods;
  • Standardization in micro manufacturing and micro factories;
  • Applications of micro and nano technologies: microreactor technologies, microsensors and actuators

Prof. Dr. André Zimmermann
Prof. Dr. Stefan Dimov
Guest Editors

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Keywords

  • micro manufacturing
  • nano manufacturing
  • manufacturing technology
  • micro structures
  • nano structures
  • microtechnology
  • micromechanics
  • microoptics
  • microsystems technology
  • sensor integration
  • multi material manufacturing
  • micro fabrication
  • micro and nano additive manufacturing
  • micro-assembly
  • micro-handling
  • surface engineering and interface nanotechnology
  • standardization in micro manufacturing and micro factories
  • micro and desktop factory concepts, systems, components and modules
  • microreactors
  • microsensors
  • micro actuators

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Published Papers (14 papers)

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Editorial

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3 pages, 170 KiB  
Editorial
Special Issue on “Micro/Nano Manufacturing”
by André Zimmermann and Stefan Dimov
Appl. Sci. 2019, 9(11), 2378; https://doi.org/10.3390/app9112378 - 11 Jun 2019
Cited by 2 | Viewed by 2917
Abstract
Micro manufacturing is dealing with the fabrication of structures in the order of 0 [...] Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)

Research

Jump to: Editorial

22 pages, 10474 KiB  
Article
From Nanostructural Characterization of Nanoparticles to Performance Assessment of Low Clinker Fiber–Cement Nanohybrids
by Styliani Papatzani and Kevin Paine
Appl. Sci. 2019, 9(9), 1938; https://doi.org/10.3390/app9091938 - 11 May 2019
Cited by 9 | Viewed by 3065
Abstract
With the current paper three nano-Montmorillonites (nMt) are applied in cement nanohybrids: an organomodified nMt dispersion, nC2; an inorganic nMt dispersion, nC3; and an organomodified powder, nC4. nC4 is fully characterized in this paper (X-ray diffraction, scanning electron microscopy/X-ray energy dispersive spectroscopy and [...] Read more.
With the current paper three nano-Montmorillonites (nMt) are applied in cement nanohybrids: an organomodified nMt dispersion, nC2; an inorganic nMt dispersion, nC3; and an organomodified powder, nC4. nC4 is fully characterized in this paper (X-ray diffraction, scanning electron microscopy/X-ray energy dispersive spectroscopy and thermal gravimetric analysis/differential thermogravimetry. Consecutively a ternary non pozzolanic combination of fiber–cement nanohybrids (60% Portland cement (PC) and 40% limestone (LS)) was investigated in terms of flexural strength, thermal properties, density, porosity, and water impermeability. Flexural strength was improved after day 28, particularly with the addition of the inorganic nMt dispersion. There was no change in density or enhancement in pozzolanic reactions for the powder nMt. Mercury intrusion porosimetry showed that the pore related parameters were increased. This can be attributed to mixing effects and the presence of fibers. Water impermeability tests yielded ambiguous results. Clearly, novel manufacturing processes of cement nanohybrids must be developed to eliminate mixing issues recorded in this research. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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17 pages, 2157 KiB  
Article
A Product Development Approach in The Field of Micro-Assembly with Emphasis on Conceptual Design
by Christoph Gielisch, Karl-Peter Fritz, Anika Noack and André Zimmermann
Appl. Sci. 2019, 9(9), 1920; https://doi.org/10.3390/app9091920 - 10 May 2019
Cited by 6 | Viewed by 3342
Abstract
Faster product lifecycles make long-term investments in machines for micro assembly riskier. Therefore, reconfigurable manufacturing systems gain more and more attention. But most companies are uncertain if a reconfigurable manufacturing system can fulfill their needs and justify the initial investment. New and improved [...] Read more.
Faster product lifecycles make long-term investments in machines for micro assembly riskier. Therefore, reconfigurable manufacturing systems gain more and more attention. But most companies are uncertain if a reconfigurable manufacturing system can fulfill their needs and justify the initial investment. New and improved techniques for product development have the potential to foster the utilization and decrease the investment risk for such systems. In this paper, four different methods for product development are reviewed. A set of criteria regarding micro assembly on reconfigurable manufacturing systems RMS is established. Based on those criteria and the assessment, a novel approach for a product development method is provided, which tries to combine the strengths of the beforehand presented approaches. It focuses on the conceptual design phase to overcome the customers’ uncertainty in the development process. For this, an abstract representation of a micro-assembly product idea as well as a decision tree for joining processes are established and validated by real product ideas using expert interviews. The validation shows that the conceptual design phase can be used as a useful tool in the product development process in the field of micro assembly. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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9 pages, 2862 KiB  
Article
Low-Temperature Plasma Nitriding of Mini-/Micro-Tools and Parts by Table-Top System
by Tatsuhiko Aizawa, Hiroshi Morita and Kenji Wasa
Appl. Sci. 2019, 9(8), 1667; https://doi.org/10.3390/app9081667 - 23 Apr 2019
Cited by 10 | Viewed by 3010
Abstract
Miniature products and components must be surface treated to improve their wear resistance and corrosion toughness. Among various processes, low-temperature plasma nitriding was employed to harden the outer and inner surfaces of micro-nozzles and to strengthen the micro-springs. A table-top nitriding system was [...] Read more.
Miniature products and components must be surface treated to improve their wear resistance and corrosion toughness. Among various processes, low-temperature plasma nitriding was employed to harden the outer and inner surfaces of micro-nozzles and to strengthen the micro-springs. A table-top nitriding system was developed even for simultaneous treatment of nozzles and springs. A single AISI316 micro-nozzle was nitrided at 673 K for 7.2 ks to have a surface hardness of 2000 HV0.02 and nitrogen solute content up to 10 mass%. In particular, the inner and outer surfaces of a micro-nozzle outlet were uniformly nitrided. In addition, the surface contact angle increased from 40° for bare stainless steels to 104° only by low-temperature plasma nitriding. A stack of micro-nozzles was simultaneously nitrided for mass production. Micro-springs were also nitrided to improve their stiffness for medical application. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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12 pages, 4821 KiB  
Article
Tunable Silver Nanoparticle Arrays by Hot Embossing and Sputter Deposition for Surface-Enhanced Raman Scattering
by Chu-Yu Huang and Ming-Shiuan Tsai
Appl. Sci. 2019, 9(8), 1636; https://doi.org/10.3390/app9081636 - 19 Apr 2019
Cited by 8 | Viewed by 3865
Abstract
Surface-enhanced Raman scattering (SERS) spectroscopy has attracted a lot of attention over the past 30 years. Due to its extreme sensitivity and label-free detection capability, it has shown great potential in areas such as analytical chemistry, biochemistry, and environmental science. However, the major [...] Read more.
Surface-enhanced Raman scattering (SERS) spectroscopy has attracted a lot of attention over the past 30 years. Due to its extreme sensitivity and label-free detection capability, it has shown great potential in areas such as analytical chemistry, biochemistry, and environmental science. However, the major challenge is to manufacture large-scale highly SERS active substrates with high controllability, good reproducibility, and low cost. In this study, we report a novel method to fabricate uniform silver nanoparticle arrays with tunable particle sizes and interparticle gaps. Using hot embossing and sputtering techniques, we were able to batch produce the silver nanoparticle arrays SERS active substrate with consistent quality and low cost. We showed that the proposed SERS active substrate has good uniformity and high reproducibility. Experimental results show that the SERS enhancement factor is affected by silver nanoparticles size and interparticle gaps. Furthermore, the enhancement factor of the SERS signal obtained from Rhodamine 6G (R6G) probe molecules was as high as 1.12 × 107. Therefore, the developed method is very promising for use in many SERS applications. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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13 pages, 5867 KiB  
Article
Effect of Process Parameters on the Generated Surface Roughness of Down-Facing Surfaces in Selective Laser Melting
by Amal Charles, Ahmed Elkaseer, Lore Thijs, Veit Hagenmeyer and Steffen Scholz
Appl. Sci. 2019, 9(6), 1256; https://doi.org/10.3390/app9061256 - 26 Mar 2019
Cited by 124 | Viewed by 8716
Abstract
Additive manufacturing provides a number of benefits in terms of infinite freedom to design complex parts and reduced lead-times while globally reducing the size of supply chains as it brings all production processes under one roof. However, additive manufacturing (AM) lags far behind [...] Read more.
Additive manufacturing provides a number of benefits in terms of infinite freedom to design complex parts and reduced lead-times while globally reducing the size of supply chains as it brings all production processes under one roof. However, additive manufacturing (AM) lags far behind conventional manufacturing in terms of surface quality. This proves a hindrance for many companies considering investment in AM. The aim of this work is to investigate the effect of varying process parameters on the resultant roughness of the down-facing surfaces in selective laser melting (SLM). A systematic experimental study was carried out and the effects of the interaction of the different parameters and their effect on the surface roughness (Sa) were analyzed. It was found that the interaction and interdependency between parameters were of greatest significance to the obtainable surface roughness, though their effects vary greatly depending on the applied levels. This behavior was mainly attributed to the difference in energy absorbed by the powder. Predictive process models for optimization of process parameters for minimizing the obtained Sa in 45° and 35° down-facing surface, individually, were achieved with average error percentages of 5% and 6.3%, respectively, however further investigation is still warranted. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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17 pages, 2891 KiB  
Article
Spatial Uncertainty Modeling for Surface Roughness of Additively Manufactured Microstructures via Image Segmentation
by Namjung Kim, Chen Yang, Howon Lee and Narayana R. Aluru
Appl. Sci. 2019, 9(6), 1093; https://doi.org/10.3390/app9061093 - 15 Mar 2019
Cited by 8 | Viewed by 3630
Abstract
Despite recent advances in additive manufacturing (AM) that shifts the paradigm of modern manufacturing by its fast, flexible, and affordable manufacturing method, the achievement of high-dimensional accuracy in AM to ensure product consistency and reliability is still an unmet challenge. This study suggests [...] Read more.
Despite recent advances in additive manufacturing (AM) that shifts the paradigm of modern manufacturing by its fast, flexible, and affordable manufacturing method, the achievement of high-dimensional accuracy in AM to ensure product consistency and reliability is still an unmet challenge. This study suggests a general method to establish a mathematical spatial uncertainty model based on the measured geometry of AM microstructures. Spatial uncertainty is specified as the deviation between the planned and the actual AM geometries of a model structure, high-aspect-ratio struts. The detailed steps of quantifying spatial uncertainties in the AM geometry are as follows: (1) image segmentation to extract the sidewall profiles of AM geometry; (2) variability-based sampling; (3) Gaussian process modeling for spatial uncertainty. The modeled spatial uncertainty is superimposed in the CAD geometry and finite element analysis is performed to quantify its effect on the mechanical behavior of AM struts with different printing angles under compressive loading conditions. The results indicate that the stiffness of AM struts with spatial uncertainty is reduced to 70% of the stiffness of CAD geometry and the maximum von Mises stress under compressive loading is significantly increased by the spatial uncertainties. The proposed modeling framework enables the high fidelity of computer-based predictive tools by seamlessly incorporating spatial uncertainties from digital images of AM parts into a traditional finite element model. It can also be applied to parts produced by other manufacturing processes as well as other AM techniques. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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10 pages, 12691 KiB  
Article
Fabrication of Multiscale-Structure Wafer-Level Microlens Array Mold
by Shuping Xie, Xinjun Wan and Xiaoxiao Wei
Appl. Sci. 2019, 9(3), 487; https://doi.org/10.3390/app9030487 - 31 Jan 2019
Cited by 5 | Viewed by 5814
Abstract
The design and manufacture of cost-effective miniaturized optics at wafer level, using
advanced semiconductor-like techniques, enables the production of reduced form-factor camera
modules for optical devices. However, suppressing the Fresnel reflection of wafer-level microlenses
is a major challenge. Moth-eye nanostructures not only satisfy [...] Read more.
The design and manufacture of cost-effective miniaturized optics at wafer level, using
advanced semiconductor-like techniques, enables the production of reduced form-factor camera
modules for optical devices. However, suppressing the Fresnel reflection of wafer-level microlenses
is a major challenge. Moth-eye nanostructures not only satisfy the antireflection requirement
of microlens arrays, but also overcome the problem of coating fracture. This novel fabrication
process, based on a precision wafer-level microlens array mold, is designed to meet the demand
for small form factors, high resolution, and cost effectiveness. In this study, three different kinds of
aluminum material, namely 6061-T6 aluminum alloy, high-purity polycrystalline aluminum, and pure
nanocrystalline aluminum were used to fabricate microlens array molds with uniform nanostructures.
Of these three materials, the pure nanocrystalline aluminum microlens array mold exhibited a
uniform nanostructure and met the optical requirements. This study lays a solid foundation for the
industrial acceptation of novel and functional multiscale-structure wafer-level microlens arrays and
provides a practical method for the low-cost manufacture of large, high-quality wafer-level molds. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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15 pages, 11130 KiB  
Article
Miniaturized Optical Encoder with Micro Structured Encoder Disc
by Jonathan Seybold, André Bülau, Karl-Peter Fritz, Alexander Frank, Cor Scherjon, Joachim Burghartz and André Zimmermann
Appl. Sci. 2019, 9(3), 452; https://doi.org/10.3390/app9030452 - 29 Jan 2019
Cited by 17 | Viewed by 15602
Abstract
A novel optical incremental and absolute encoder based on an optical application-specific integrated circuit (opto-ASIC) and an encoder disc carrying micro manufactured structures is presented. The physical basis of the encoder is the diffraction of light using a reflective phase grating. The opto-ASIC [...] Read more.
A novel optical incremental and absolute encoder based on an optical application-specific integrated circuit (opto-ASIC) and an encoder disc carrying micro manufactured structures is presented. The physical basis of the encoder is the diffraction of light using a reflective phase grating. The opto-ASIC contains a ring of photodiodes that represents the encryption of the encoder. It also includes the analog signal conditioning, the signal acquisition, and the control of a light source, as well as the digital position processing. The development and fabrication of the opto-ASIC is also described in this work. A laser diode was assembled in the center on top of the opto-ASIC, together with a micro manufactured polymer lens. The latter was fabricated using ultra-precision machining. The encoder disc was fabricated using micro injection molding and contains micro structures forming a blazed grating. This way, a 10-bit optical encoder with a form factor of only 1 cm3 was realized and tested successfully. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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10 pages, 2488 KiB  
Article
Fabrication of a Novel Culture Dish Adapter with a Small Recess Structure for Flow Control in a Closed Environment
by Reiko Yasuda, Shungo Adachi, Atsuhito Okonogi, Youhei Anzai, Tadataka Kamiyama, Keiji Katano, Nobuhiko Hoshi, Tohru Natsume and Katsuo Mogi
Appl. Sci. 2019, 9(2), 269; https://doi.org/10.3390/app9020269 - 14 Jan 2019
Cited by 3 | Viewed by 4832
Abstract
Cell culture medium replacement is necessary to replenish nutrients and remove waste products, and perfusion and batch media exchange methods are available. The former can establish an environment similar to that in vivo, and microfluidic devices are frequently used. However, these methods are [...] Read more.
Cell culture medium replacement is necessary to replenish nutrients and remove waste products, and perfusion and batch media exchange methods are available. The former can establish an environment similar to that in vivo, and microfluidic devices are frequently used. However, these methods are hampered by incompatibility with commercially available circular culture dishes and the difficulty in controlling liquid flow. Here, we fabricated a culture dish adapter using polydimethylsiloxane that has a small recess structure for flow control compatible with commercially available culture dishes. We designed U-shaped and I-shaped recess structure adapters and we examined the effects of groove structure on medium flow using simulation. We found that the U-shaped and I-shaped structures allowed a uniform and uneven flow of medium, respectively. We then applied these adaptors to 293T cell culture and examined the effects of recess structures on cell proliferation. As expected, cell proliferation was similar in each area of a dish in the U-shaped structure adapter, whereas in the early flow area in the I-shaped structure adapter, it was significantly higher. In summary, we succeeded in controlling liquid flow in culture dishes with the fabricated adapter, as well as in applying the modulation of culture medium flow to control cell culture. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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22 pages, 5169 KiB  
Article
Improving Surface Roughness of Additively Manufactured Parts Using a Photopolymerization Model and Multi-Objective Particle Swarm Optimization
by Namjung Kim, Ishan Bhalerao, Daehoon Han, Chen Yang and Howon Lee
Appl. Sci. 2019, 9(1), 151; https://doi.org/10.3390/app9010151 - 3 Jan 2019
Cited by 26 | Viewed by 6871
Abstract
Although additive manufacturing (AM) offers great potential to revolutionize modern manufacturing, its layer-by-layer process results in a staircase-like rough surface profile of the printed part, which degrades dimensional accuracy and often leads to a significant reduction in mechanical performance. In this paper, we [...] Read more.
Although additive manufacturing (AM) offers great potential to revolutionize modern manufacturing, its layer-by-layer process results in a staircase-like rough surface profile of the printed part, which degrades dimensional accuracy and often leads to a significant reduction in mechanical performance. In this paper, we present a systematic approach to improve the surface profile of AM parts using a computational model and a multi-objective optimization technique. A photopolymerization model for a micro 3D printing process, projection micro-stereolithography (PμSL), is implemented by using a commercial finite element solver (COMSOL Multiphysics software). First, the effect of various process parameters on the surface roughness of the printed part is analyzed using Taguchi’s method. Second, a metaheuristic optimization algorithm, called multi-objective particle swarm optimization, is employed to suggest the optimal PμSL process parameters (photo-initiator and photo-absorber concentrations, layer thickness, and curing time) that minimize two objectives; printing time and surface roughness. The result shows that the proposed optimization framework increases 18% of surface quality of the angled strut even at the fastest printing speed, and also reduces 50% of printing time while keeping the surface quality equal for the vertical strut, compared to the samples produced with non-optimized parameters. The systematic approach developed in this study significantly increase the efficiency of optimizing the printing parameters compared to the heuristic approach. It also helps to achieve 3D printed parts with high surface quality in various printing angles while minimizing printing time. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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12 pages, 11762 KiB  
Article
Manufacturing of Micro-Lens Array Using Contactless Micro-Embossing with an EDM-Mold
by Kangsen Li, Gang Xu, Xinfang Huang, Zhiwen Xie and Feng Gong
Appl. Sci. 2019, 9(1), 85; https://doi.org/10.3390/app9010085 - 26 Dec 2018
Cited by 23 | Viewed by 5663
Abstract
Micro embossing is an effective way to fabricate a polymethyl methacrylate (PMMA) specimen into micro-scale array structures with low cost and large volume production. A new method was proposed to fabricate a micro-lens array using a micro-electrical discharge machining (micro-EDM) mold. The micro-lens [...] Read more.
Micro embossing is an effective way to fabricate a polymethyl methacrylate (PMMA) specimen into micro-scale array structures with low cost and large volume production. A new method was proposed to fabricate a micro-lens array using a micro-electrical discharge machining (micro-EDM) mold. The micro-lens array with different shapes was established by controlling the processing parameters, including embossing temperature, embossing force, and holding time. In order to obtain the friction coefficient between the PMMA and the mold, ring compression tests were conducted on the Shenzhen University’s precision glass molding machine (SZU’s PGMM30). It was found that the friction coefficient between the PMMA specimen and the mold had an interesting change process with increasing of temperature, which affected the final shape and stress distribution of the compressed PMMA parts. The results of micro-optical imaging of micro-lens array indicated that the radius of curvature and local length could be controlled by adjusting the processing parameters. This method provides a basis for the fabrication and application of micro-lens arrays with low-cost, high efficiency, and mass production. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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15 pages, 3762 KiB  
Article
Chatter Identification of Three-Dimensional Elliptical vibration Cutting Process Based on Empirical Mode Decomposition and Feature Extraction
by Mingming Lu, Bin Chen, Dongpo Zhao, Jiakang Zhou, Jieqiong Lin, Allen Yi and Hao Wang
Appl. Sci. 2019, 9(1), 21; https://doi.org/10.3390/app9010021 - 21 Dec 2018
Cited by 4 | Viewed by 3343
Abstract
Three-dimensional elliptical vibration cutting (3D-EVC) is one of the machining methods with the most potential in ultra-precision machining; its unique characteristics of intermittent cutting, friction reversal, and ease of chip removal can improve the machinability of materials in the cutting processes. However, there [...] Read more.
Three-dimensional elliptical vibration cutting (3D-EVC) is one of the machining methods with the most potential in ultra-precision machining; its unique characteristics of intermittent cutting, friction reversal, and ease of chip removal can improve the machinability of materials in the cutting processes. However, there is still not much research about the chattering phenomenon in the 3D-EVC process. Therefore, based on the empirical mode decomposition (EMD) technique and feature extraction, a chatter identification method for 3D-EVC is proposed. In 3D-EVC operations, the vibration signal is collected by the displacement sensors and converted to frequency domain signal by fast Fourier transform (FFT). To identify tool cutting state using the vibration frequency signal, the vibration signals are decomposed using empirical mode decomposition (EMD), a series of intrinsic mode functions (IMFs), so the instantaneous frequency can be reflected by the vibration signals at any point. Then, selecting the primary IMFs which contain rich chatter information as the object in feature extraction identification, and two identification indexes, that is, the mean square frequency and self-correlation coefficient, are calculated for the primary IMFs by MATLAB software, to judge the chatter phenomenon. The experimental results showed that the mean square frequency and self-correlation coefficient of the three cutting states increase with the increase in the instability of the cutting state. The effectiveness of the improved chatter recognition method in 3D-EVC machining is verified. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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21 pages, 9899 KiB  
Article
Theoretical Study of Path Adaptability Based on Surface Form Error Distribution in Fluid Jet Polishing
by Yanjun Han, Lei Zhang, Cheng Fan, Wule Zhu and Anthony Beaucamp
Appl. Sci. 2018, 8(10), 1814; https://doi.org/10.3390/app8101814 - 3 Oct 2018
Cited by 21 | Viewed by 3799
Abstract
In the technology of computer-controlled optical surfacing (CCOS), the convergence of surface form error has a close relationship with the distribution of surface form error, the calculation of dwell time, tool influence function (TIF) and path planning. The distribution of surface form error [...] Read more.
In the technology of computer-controlled optical surfacing (CCOS), the convergence of surface form error has a close relationship with the distribution of surface form error, the calculation of dwell time, tool influence function (TIF) and path planning. The distribution of surface form error directly reflects the difference in bulk material removal depth across a to-be-polished surface in subsequent corrective polishing. In this paper, the effect of path spacing and bulk material removal depth on the residual error have been deeply investigated based on basic simulation experiments excluding the interference factors in the actual polishing process. With the relationship among the critical evaluation parameters of the residual error (root-mean-square (RMS) and peak-to-valley (PV)), the path spacing and bulk material removal depth are mathematically characterized by the proposed RMS and PV maps, respectively. Moreover, a variable pitch path self-planning strategy based on the distribution of surface form error is proposed to optimize the residual error distribution. In the proposed strategy, the influence of different bulk material removal depths caused by the distribution of surface form error on residual error is compensated by fine adjustment of the path spacing according to the obtained path spacing optimization models. The simulated experimental results demonstrate that the residual error optimization strategy proposed in this paper can significantly optimize the overall residual error distribution without compromising the convergence speed. The optimized residual error distribution obtained in sub-regions of the polished surface is more uniform than that without optimization and is almost unaffected by the distribution of parent surface form error. Full article
(This article belongs to the Special Issue Micro/Nano Manufacturing)
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