Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
5.2
3.4
Journals
Materials
Special Issues
Novel Material and Technological Solutions in Foundry Engineering
materials-logo
Submit to Materials Review for Materials Propose a Special Issue

Journal Menu

► Journal Menu

Journal Browser

► Journal Browser
share announcement

Novel Material and Technological Solutions in Foundry Engineering

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Manufacturing Processes and Systems".

Deadline for manuscript submissions: closed (20 April 2022) | Viewed by 34089

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editor

Prof. Dr. Tomasz Wróbel

E-Mail Website
Guest Editor
Department of Foundry Engineering, Silesian University of Technology, 7 Towarowa Street, 44-100 Gliwice, Poland
Interests: cast steel; cast iron; Al alloys; layered castings; heat treatment
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Foundry engineering is still a strongly developing field of material science and an important branch of production of metallic materials. Publications concerning foundry engineering are very popular and usable for many academic scientists and engineering work in many industries. Therefore, given the great potential for development in this field of science and industry, I invite you to submit your valuable articles to this Special Issue entitled “Novel Material and Technological Solutions in Foundry Engineering”, published in the journal Materials. The scope of this Special Issue is focused on cast materials characterized by high usable properties. The issue covers both ferrous alloys, such as cast steel or cast iron, and nonferrous metals alloys, such as Al, Cu, Mg, and others. Moreover, as the title suggests, this Special Issue welcomes articles concerning technologies of layered and composite castings, pressure casting, semi-solid casting, continuous casting, and new technology of heat treatment of castings.

Once again, I cordially invite you to submit your original research papers or review articles that describe the current state of the art within the scope of this Special Issue “Novel Material and Technological Solutions in Foundry Engineering”.

Prof. Dr. Tomasz Wróbel
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Foundry engineering
  • Ferrous and nonferrous alloys
  • Innovative foundry technologies
  • Solidification and crystallization of metals and alloys
  • Computer simulation of foundry processes
  • Castings quality
  • Methods of castings repair
  • Microstructure
  • Mechanical properties

Published Papers (15 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

26 pages, 9384 KiB  
Article
Influence of Al/Ti Ratio and Ta Concentration on the As-Cast Microstructure, Phase Composition, and Phase Transformation Temperatures of Lost-Wax Ni-Based Superalloy Castings
by Małgorzata Grudzień-Rakoczy, Łukasz Rakoczy, Rafał Cygan, Konrad Chrzan, Ondrej Milkovič and Zenon Pirowski
Materials 2022, 15(9), 3296; https://doi.org/10.3390/ma15093296 - 4 May 2022
Cited by 2 | Viewed by 1592
Abstract
The as-cast microstructure, alloying element segregation, solidification behavior, and thermal stability of model superalloys based on Inconel 740 with various Al/Ti ratios (0.7, 1.5, 3.4) and Ta (2.0, 3.0, 4.0 wt%) concentrations were investigated via ThermoCalc simulations, scanning and transmission electron microscopy, energy-dispersive [...] Read more.
The as-cast microstructure, alloying element segregation, solidification behavior, and thermal stability of model superalloys based on Inconel 740 with various Al/Ti ratios (0.7, 1.5, 3.4) and Ta (2.0, 3.0, 4.0 wt%) concentrations were investigated via ThermoCalc simulations, scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, dilatometry, and differential scanning calorimetry. The solidification of the superalloys began with the formation of primary γ dendrites, followed by MC carbides. The type of subsequently formed phases depended on the superalloys’ initial Al/Ti ratio and Ta concentration. The results obtained from solidification simulations were compared to the obtained microstructures. For all castings, the dendritic regions consisted of fine γ′ precipitates, with their size mainly depending on the initial Al/Ti ratio, whereas in the interdendritic spaces, (Nb, Ta, Ti)C carbides and Nb-rich Laves phase precipitates were present. In high Al/Ti ratio superalloys, β-NiAl precipitates, strengthened by η and α-Cr phases, were observed. Based on dilatometric results, the dissolution of γ′ precipitates was accompanied by a substantial increase in the coefficient of thermal expansion. The end of the dilatation effect took place around the γ′ solvus temperature, as determined via calorimetry. Moreover, the bulk solidus temperature was preceded by the dissolution of the Laves phase, which may be accompanied by local melting. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

15 pages, 8133 KiB  
Article
Surface Phenomena at the Interface between Silicon Carbide and Iron Alloy
by Mirosław Cholewa, Tomasz Wróbel, Czesław Baron and Marcin Morys
Materials 2021, 14(22), 6762; https://doi.org/10.3390/ma14226762 - 10 Nov 2021
Viewed by 1302
Abstract
The paper discusses a potential composite produced using the casting method, where the matrix is gray cast iron with flake graphite. The reinforcement is provided by granular carborundum (β-SiC). The article presents model studies aimed at identifying the phenomena at the contact boundary [...] Read more.
The paper discusses a potential composite produced using the casting method, where the matrix is gray cast iron with flake graphite. The reinforcement is provided by granular carborundum (β-SiC). The article presents model studies aimed at identifying the phenomena at the contact boundary resulting from the interaction of the liquid matrix with solid reinforcement particles. The scope of the research included, primarily, the metallographic analysis of the microstructure of the resulting composite, carried out by using light (LOM) and scanning electron (SEM) microscopy with energy dispersive X-ray spectroscopy (EDS) analysis. The occurrence of metallic phases in the boundary zone was indicated, the contents and morphology of which can be optimized in order to achieve favorable functional properties, mainly the tribological properties of the composite. In addition, the results obtained confirm the possibility of producing similar composites based on selected iron alloys. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

15 pages, 10578 KiB  
Article
Shaping the Microstructure of High-Aluminum Cast Iron in Terms of the Phenomenon of Spontaneous Decomposition Generated by the Presence of Aluminum Carbide
by Robert Gilewski, Dariusz Kopyciński, Edward Guzik and Andrzej Szczęsny
Materials 2021, 14(20), 5993; https://doi.org/10.3390/ma14205993 - 12 Oct 2021
Cited by 3 | Viewed by 1361
Abstract
A suitable aluminum additive in cast iron makes it resistant to heat in a variety of environments and increases the abrasion resistance of the cast iron. It should be noted that high-aluminum cast iron has the potential to become an important eco-material. The [...] Read more.
A suitable aluminum additive in cast iron makes it resistant to heat in a variety of environments and increases the abrasion resistance of the cast iron. It should be noted that high-aluminum cast iron has the potential to become an important eco-material. The basic elements from which it is made—iron, aluminum and a small amount of carbon—are inexpensive components. This material can be made from contaminated aluminum scrap, which is increasingly found in metallurgical scrap. The idea is to produce iron castings with the highest possible proportion of aluminum. Such castings are heat-resistant and have good abrasive properties. The only problem to be solved is to prevent the activation of the phenomenon of spontaneous decomposition. This phenomenon is related to the Al4C3 hygroscopic aluminum carbide present in the structure of cast iron. Previous attempts to determine the causes of spontaneous disintegration by various researchers do not describe them comprehensively. In this article, the mechanism of the spontaneous disintegration of high-aluminum cast iron castings is defined. The main factor is the large relative geometric dimensions of Al4C3 carbide. In addition, methods for counteracting the phenomenon of spontaneous decay are developed, which is the main goal of the research. It is found that a reduction in the size of the Al4C3 carbide or its removal lead to the disappearance of the self-disintegration effect of high-aluminum cast iron. For this purpose, an increased cooling rate of the casting is used, as well as the addition of elements (Ti, B and Bi) to cast iron, supported in some cases by heat treatment. The tests are conducted on the cast iron with the addition of 34–36% mass aluminum. The molten metal is superheated to 1540 °C and then the cast iron samples are cast at 1420 °C. A molding sand with bentonite is used to produce casting molds. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

16 pages, 7723 KiB  
Article
Non-Equilibrium Crystallization of Monotectic Zn-25%Bi Alloy under 600 g
by Grzegorz Boczkal, Pawel Palka, Piotr Kokosz, Sonia Boczkal and Grazyna Mrowka-Nowotnik
Materials 2021, 14(15), 4341; https://doi.org/10.3390/ma14154341 - 3 Aug 2021
Viewed by 2024
Abstract
This study investigated the influence of supergravity on the segregation of components in the Zn–Bi monotectic system and consequently, the creation of an interface of the separation zone of both phases. The observation showed that near the separation boundary, in a very narrow [...] Read more.
This study investigated the influence of supergravity on the segregation of components in the Zn–Bi monotectic system and consequently, the creation of an interface of the separation zone of both phases. The observation showed that near the separation boundary, in a very narrow area of the order of several hundred microns, all types of structures characteristic for the concentration range from 0 to 100% bismuth occurred. An additional effect of crystallization in high gravity is a high degree of structural order and an almost perfectly flat separation boundary. This is the case for both the zinc-rich zone and the bismuth-rich zone. Texture analysis revealed the existence of two privileged orientations in the zinc zone. Gravitational segregation also resulted in a strong rearrangement of the heavier bismuth to the outer end of the sample, leaving only very fine precipitates in the zinc region. For comparison, the results obtained for the crystallization under normal gravity are given. The effect of high orderliness of the structure was then absent. Despite segregation, a significant part of bismuth remained in the form of precipitates in the zinc matrix, and the separation border was shaped like a lens. The described method can be used for the production of massive bimaterials with a directed orientation of both components and a flat interface between them, such as thermo-generator elements or bimetallic electric cell parts, where the parameters (thickness) of the junction can be precisely defined at the manufacturing stage. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

14 pages, 46282 KiB  
Article
Comprehensive Research and Analysis of a Coated Machining Tool with a New TiAlN Composite Microlayer Using Magnetron Sputtering
by Štefan Michna, Iryna Hren, Jan Novotný, Lenka Michnová and Václav Švorčík
Materials 2021, 14(13), 3633; https://doi.org/10.3390/ma14133633 - 29 Jun 2021
Cited by 2 | Viewed by 1757
Abstract
The application of thin monolayers helps to increase the endurance of a cutting tool during the drilling process. One such trendy coating is TiAlN, which guarantees high wear resistance and helps to “smooth out” surface defects. For this reason, a new type of [...] Read more.
The application of thin monolayers helps to increase the endurance of a cutting tool during the drilling process. One such trendy coating is TiAlN, which guarantees high wear resistance and helps to “smooth out” surface defects. For this reason, a new type of weak TiAlN microlayer with a new composition has been developed and applied using the HIPIMs magnetron sputtering method. The aim of this study was to analyze surface-applied micro coatings, including chemical composition (EDX) and microstructure in the area of the coatings. Microstructural characterization and visualization of the surface structures of the TiAlN layer were performed using atomic force microscopy. To study the surface layer of the coatings, metallographic cross-sectional samples were prepared and monitored using light and electron microscopy methods. The microhardness of the test layer was also determined. Analyses have shown that a 2-to-4-micron thick monolayer has a microhardness of about 2500 HV, which can help increase the life of cutting tools. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

21 pages, 7600 KiB  
Article
Dehydroxylation of Perlite and Vermiculite: Impact on Improving the Knock-Out Properties of Moulding and Core Sand with an Inorganic Binder
by Artur Bobrowski, Karolina Kaczmarska, Maciej Sitarz, Dariusz Drożyński, Magdalena Leśniak, Beata Grabowska and Daniel Nowak
Materials 2021, 14(11), 2946; https://doi.org/10.3390/ma14112946 - 29 May 2021
Cited by 3 | Viewed by 2485
Abstract
The article presents the results of research aimed at examining the type of swelling material introduced into moulding or core sand to improve their knock-out properties. Tests on Slovak perlite ore (three grain sizes), Hungarian perlite ore and ground vermiculite (South Africa) were [...] Read more.
The article presents the results of research aimed at examining the type of swelling material introduced into moulding or core sand to improve their knock-out properties. Tests on Slovak perlite ore (three grain sizes), Hungarian perlite ore and ground vermiculite (South Africa) were carried out. For this purpose, thermal and structural analyses (FTIR—Fourier Transform Infrared Spectroscopy), a chemical composition test (XRF-X-Ray Fluorescence), phase analysis (XRD—X-Ray Diffraction), and scanning electron microscopy (SEM—Scanning Electron Microscope) as well as final strength tests of moulding sands with the addition of perlite ore and vermiculite were carried out. The results of thermal studies were related to IR (Infrared Spectroscopy) spectra and XRD diffractograms. It has been shown that the water content in the pearlite ore is almost three times lower than in vermiculite, but the process of its removal is different. Moreover, the chemical composition of the perlite ore, in particular the alkali content and its grain size, may influence its structure. The phenomena of expansion (perlite) and peeling (vermiculite) have a positive effect on the reduction of the final sand strength and eliminate technological inconveniences (poor knocking out) that significantly limit the wide use of moulding sands with inorganic binders. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

10 pages, 9086 KiB  
Article
Repair of a Cracked Historic Maryan Bell by Gas Welding
by Dariusz Bartocha and Czesław Baron
Materials 2021, 14(10), 2504; https://doi.org/10.3390/ma14102504 - 12 May 2021
Cited by 1 | Viewed by 1522
Abstract
In this article, the range of works connected with the repair of a historical Maryan bell from 1639 are presented. The first attempts to repair damaged bells occurred in the 1930s in Poland. However, this process was stopped because of extensive technological difficulties. [...] Read more.
In this article, the range of works connected with the repair of a historical Maryan bell from 1639 are presented. The first attempts to repair damaged bells occurred in the 1930s in Poland. However, this process was stopped because of extensive technological difficulties. Welding and soldering-welding were the basic methods. There is one difference between these two methods—connecting surfaces are melted during the welding process but only heated until the melting temperature of the material added to the connection (that is the solder) during the soldering-welding process. It was important to heat the bell to the proper temperature during welding. Uneven heating causes the enlargement of existing cracks or the appearance of new ones, or even the complete destruction of the bell. Nowadays, a method of even heating using a special heating mat has been devised. Thanks to this method it is possible to control the heating and cooling process. The most important task during the whole operation of bell welding was obtaining the original sound. During this research, the chemical composition was examined to prepare a welding rod with a suitable chemical composition. After the repair process, an analysis of the sound of the bell was conducted. It was shown that the repair of bells is possible when correct thermal parameters are used. The most highly recommended technique for repairing bells is gas welding. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

17 pages, 7399 KiB  
Article
Effect of Chromium and Molybdenum Addition on the Microstructure of In Situ TiC-Reinforced Composite Surface Layers Fabricated on Ductile Cast Iron by Laser Alloying
by Damian Janicki
Materials 2020, 13(24), 5750; https://doi.org/10.3390/ma13245750 - 16 Dec 2020
Cited by 5 | Viewed by 1846
Abstract
In situ TiC-reinforced composite surface layers (TRLs) were produced on a ductile cast iron substrate by laser surface alloying (LA) using pure Ti powder and mixtures of Ti-Cr and Ti-Mo powders. During LA with pure Ti, the intensity of fluid flow in the [...] Read more.
In situ TiC-reinforced composite surface layers (TRLs) were produced on a ductile cast iron substrate by laser surface alloying (LA) using pure Ti powder and mixtures of Ti-Cr and Ti-Mo powders. During LA with pure Ti, the intensity of fluid flow in the molten pool, which determines the TRL’s compositional uniformity, and thus Ti content in the alloyed zone, was directly affected by the fraction of synthesized TiC particles in the melt—with increasing the TiC fraction, the convection was gradually reduced. The introduction of additional Cr or Mo powders into the molten pool, due to their beneficial effect on the intensity of the molten pool convection, elevated the Ti concentration in the melt, and, thus, the TiC fraction in the TRL. It was found that the melt enrichment of Cr, in conjunction with non-equilibrium cooling conditions, suppressed the martensitic transformation of the matrix, which lowered the total hardness of the TRL. Moreover, the presence of Cr in the melt (~3 wt%) altered the growth morphology of the synthesized primary TiC precipitates compared with that obtained using pure Ti. The addition of Mo in the melt produced (Ti, Mo)C primary precipitates that exhibited a nonuniform Mo distribution (coring structure). The dissolution of Mo in the primary TiC precipitates did not affect its growth morphology. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

13 pages, 9352 KiB  
Article
Development and Optimization of Tin/Flux Mixture for Direct Tinning and Interfacial Bonding in Aluminum/Steel Bimetallic Compound Casting
by Mohamed Ramadan, Abdulaziz S. Alghamdi, K. M. Hafez, Tayyab Subhani and K. S. Abdel Halim
Materials 2020, 13(24), 5642; https://doi.org/10.3390/ma13245642 - 10 Dec 2020
Cited by 14 | Viewed by 2156
Abstract
Interfacial bonding highly affects the quality of bimetallic bearing materials, which primarily depend upon the surface quality of a solid metal substrate in liquid–solid compound casting. In many cases, an intermediate thin metallic layer is deposited on the solid substrate before depositing the [...] Read more.
Interfacial bonding highly affects the quality of bimetallic bearing materials, which primarily depend upon the surface quality of a solid metal substrate in liquid–solid compound casting. In many cases, an intermediate thin metallic layer is deposited on the solid substrate before depositing the liquid metal, which improves the interfacial bonding of the opposing materials. The present work aims to develop and optimize the tinning process of a solid carbon steel substrate after incorporating flux constituents with the tin powder. Five ratios of tin-to-flux—i.e., 1:1, 1:5, 1:10, 1:15, and 1:20—were used for tinning process of carbon steel solid substrate. Furthermore, the effect of volume ratios of liquid Al-based bearing alloy to solid steel substrate were also varied—i.e., 5:1, 6.5:1 and 8.5:1—to optimize the microstructural and mechanical performance, which were evaluated by interfacial microstructural investigation, bonding area determination, hardness and interfacial strength measurements. It was found that a tin-to-flux ratio of 1:10 offered the optimum performance in AlSn12Si4Cu1/steel bimetallic materials, showing a homogenous and continuous interfacial layer structure, while tinned steels using other percentages showed discontinuous and thin layers, as in 1:5 and 1:15, respectively. Furthermore, bimetallic interfacial bonding area and hardness increased by increasing the volume ratio of liquid Al alloy to solid steel substrate. A complete interface bonding area was achieved by using the volume ratio of liquid Al alloy to solid steel substrate of ≥8.5. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

13 pages, 3360 KiB  
Article
Characteristics of Al-Si Alloys with High Melting Point Elements for High Pressure Die Casting
by Tomasz Szymczak, Grzegorz Gumienny, Leszek Klimek, Marcin Goły, Jan Szymszal and Tadeusz Pacyniak
Materials 2020, 13(21), 4861; https://doi.org/10.3390/ma13214861 - 29 Oct 2020
Cited by 10 | Viewed by 2307
Abstract
This paper is devoted to the possibility of increasing the mechanical properties (tensile strength, yield strength, elongation and hardness) of high pressure die casting (HPDC) hypoeutectic Al-Si alloys by high melting point elements: chromium, molybdenum, vanadium and tungsten. EN AC-46000 alloy was used [...] Read more.
This paper is devoted to the possibility of increasing the mechanical properties (tensile strength, yield strength, elongation and hardness) of high pressure die casting (HPDC) hypoeutectic Al-Si alloys by high melting point elements: chromium, molybdenum, vanadium and tungsten. EN AC-46000 alloy was used as a base alloy. The paper presents the effect of Cr, Mo, V and W on the crystallization process and the microstructure of HPDC aluminum alloy as well as an alloy from the shell mold. Thermal and derivative analysis was used to study the crystallization process. The possibility of increasing the mechanical properties of HPDC hypoeutectic alloy by addition of high-melting point elements has been demonstrated. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

16 pages, 10909 KiB  
Article
Study of Natural and Artificial Aging on AlSi9Cu3 Alloy at Different Ratios of Returnable Material in the Batch
by Dana Bolibruchová, Marek Matejka, Alena Michalcová and Justyna Kasińska
Materials 2020, 13(20), 4538; https://doi.org/10.3390/ma13204538 - 13 Oct 2020
Cited by 3 | Viewed by 2227
Abstract
Aluminum alloys currently play an important role in the production of castings in various industries, where important requirements include low component weight, reduction of the environmental impact and, above all, reduction of production costs of castings. One way to achieve these goals is [...] Read more.
Aluminum alloys currently play an important role in the production of castings in various industries, where important requirements include low component weight, reduction of the environmental impact and, above all, reduction of production costs of castings. One way to achieve these goals is to use recycled aluminum alloys. The effect of natural and artificial aging of AlSi9Cu3 alloy with different ratios of returnable material in the batch was evaluated by a combination of optical, scanning, transmission microscope and mechanical tests. An increase in the returnable material in the batch above 70% resulted in failure to achieve the minimum value required by the standard for tensile strength and ductility. The application of artificial aging had a positive effect on the microstructure and thus on the mechanical properties of experimental alloys. By analyzing the results from TEM, it can be stated that in the given cases there is a reduced efficiency of θ’-Al2Cu precipitate formation with an increase of the returnable material in the batch and in comparison with artificial aging, which is manifested by low mechanical properties. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Graphical abstract

24 pages, 29382 KiB  
Article
Analysis of γ′ Precipitates, Carbides and Nano-Borides in Heat-Treated Ni-Based Superalloy Using SEM, STEM-EDX, and HRSTEM
by Łukasz Rakoczy, Bogdan Rutkowski, Małgorzata Grudzień-Rakoczy, Rafał Cygan, Wiktoria Ratuszek and Anna Zielińska-Lipiec
Materials 2020, 13(19), 4452; https://doi.org/10.3390/ma13194452 - 8 Oct 2020
Cited by 15 | Viewed by 4423
Abstract
The microstructure of a René 108 Ni-based superalloy was systematically investigated by X-ray diffraction, light microscopy, energy-dispersive X-ray spectroscopy, and electron microscopy techniques. The material was investment cast in a vacuum and then solution treated (1200 °C-2h) and aged (900 °C-8h). The γ [...] Read more.
The microstructure of a René 108 Ni-based superalloy was systematically investigated by X-ray diffraction, light microscopy, energy-dispersive X-ray spectroscopy, and electron microscopy techniques. The material was investment cast in a vacuum and then solution treated (1200 °C-2h) and aged (900 °C-8h). The γ matrix is mainly strengthened by the ordered L12 γ′ phase, with the mean γ/γ′ misfit, δ, +0.6%. The typical dendritic microstructure with considerable microsegregation of the alloying elements is revealed. Dendritic regions consist of secondary and tertiary γ′ precipitates. At the interface of the matrix with secondary γ′ precipitates, nano M5B3 borides are present. In the interdendritic spaces additionally primary γ′ precipitates, MC and nano M23C6 carbides were detected. The γ′ precipitates are enriched in Al, Ta, Ti, and Hf, while channels of the matrix in Cr and Co. The highest summary concentration of γ′-formers occurs in coarse γ′ surrounding MC carbides. Borides M5B3 contain mostly W, Cr and Mo. All of MC carbides are enriched strongly in Hf and Ta, with the concentration relationship between these and other strong carbide formers depending on the precipitate’s morphology. The nano M23C6 carbides enriched in Cr have been formed as a consequence of phase transformation MC + γ → M23C6 + γ′ during the ageing treatment. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

13 pages, 4669 KiB  
Article
Non-Standard T6 Heat Treatment of the Casting of the Combustion Engine Cylinder Head
by Jacek Pezda and Jan Jezierski
Materials 2020, 13(18), 4114; https://doi.org/10.3390/ma13184114 - 16 Sep 2020
Cited by 8 | Viewed by 2419
Abstract
The introduction of new design solutions of cast components to the powertrain systems of passenger cars has resulted in an increased demand for optimization of mechanical properties obtained during heat treatment, assuring—at the same time—a suitable level of production capacity and limitation of [...] Read more.
The introduction of new design solutions of cast components to the powertrain systems of passenger cars has resulted in an increased demand for optimization of mechanical properties obtained during heat treatment, assuring—at the same time—a suitable level of production capacity and limitation of manufacturing costs. In this paper, research results concerning non-standard T6 heat treatment of a combustion engine cylinder head made of AlSi7Cu3Mg alloy are presented. It has been confirmed that the optimal process of heat treatment of this component, taking into consideration the criterion of material hardness, involves solutioning at a temperature of 500 °C for 1 h, and then aging for 2 h at 175 °C. As a result, HBS10/1000/30 hardness in the range of 105–130 was obtained, which means an increase from 35% to 60% in comparison to the as-cast, depending on the position of the measurement and spheroidization of precipitations of eutectic silicon. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Figure 1

13 pages, 3335 KiB  
Article
The Effect of Cooling Conditions on Martensite Transformation Temperature and Hardness of 15% Cr Chromium Cast Iron
by Mirosław Tupaj, Antoni Władysław Orłowicz, Andrzej Trytek, Marek Mróz, Grzegorz Wnuk and Anna Janina Dolata
Materials 2020, 13(12), 2760; https://doi.org/10.3390/ma13122760 - 18 Jun 2020
Cited by 7 | Viewed by 2249
Abstract
The research reported in the paper concerned the conditions of cooling high-chromium cast iron with about 15% Cr content capable to ensure completeness of transformation of supercooled austenite into martensite in order to obtain high hardness value of the material and thus its [...] Read more.
The research reported in the paper concerned the conditions of cooling high-chromium cast iron with about 15% Cr content capable to ensure completeness of transformation of supercooled austenite into martensite in order to obtain high hardness value of the material and thus its high resistance to abrasive wear. For testing, castings were prepared with dimensions 120 mm × 100 mm × 15 mm cast in sand molds in which one of cavity surfaces was reproduced with chills. From the castings, specimens for dilatometric tests were taken with dimensions 4 mm × 4 mm × 16 mm and plates with dimensions 50 mm × 50 mm × 15 mm for heat treatment tests. The dilatometric specimens were cut out from areas subject to interaction with the chill. The austenitizing temperature and time were 1000 °C and 30 min, respectively. Dilatograms of specimens quenched in liquid nitrogen were used to determine martensite transformation start and finish temperatures TMs and TMf, whereas from dilatograms of specimens quenched in air and in water, only TMs was red out. To secure completeness of the course of transformation of supercooled austenite into martensite and reveal the transformation finish temperature, it was necessary to continue cooling of specimens in liquid nitrogen. It has been found that TMs depended strongly on the quenching method whereas TMf values were similar for each of the adopted cooling conditions. The examined cooling variants were used to develop a heat treatment process allowing to obtain hardness of 68 HRC. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Graphical abstract

14 pages, 11365 KiB  
Article
Fabrication and Characterization of Sn-Based Babbitt Alloy Nanocomposite Reinforced with Al2O3 Nanoparticles/Carbon Steel Bimetallic Material
by Mohamed Ramadan, Abdulaziz S. Alghamdi, Tayyab Subhani and K. S. Abdel Halim
Materials 2020, 13(12), 2759; https://doi.org/10.3390/ma13122759 - 18 Jun 2020
Cited by 23 | Viewed by 2937
Abstract
Sn-based Babbitt alloy was reinforced with alumina nanoparticles to prepare a novel class of nanocomposites. The route of liquid metallurgy in combination with stirring mechanism was chosen to prepare nanocomposites with three different loadings of alumina nanoparticles, i.e., 0.25 wt%, 0.50 wt% and [...] Read more.
Sn-based Babbitt alloy was reinforced with alumina nanoparticles to prepare a novel class of nanocomposites. The route of liquid metallurgy in combination with stirring mechanism was chosen to prepare nanocomposites with three different loadings of alumina nanoparticles, i.e., 0.25 wt%, 0.50 wt% and 1.0 wt%. The molten mixture of metallic matrix and nanoparticles was poured over carbon steel substrate for solidification to manufacture a bimetallic material for bearing applications. The underlying aim was to understand the effect of nanoparticle addition on microstructural variation of Sn-based Babbitt alloy as well as bimetallic microstructural interface. The addition of 0.25 wt% and 0.50 wt% alumina nanoparticles significantly affected both the morphology and distribution of Cu6Sn5 hard phase in solid solution, which changed from needle and asterisk shape to spherical morphology. Nanocomposites containing up to 0.50 wt% nanoparticles showed more improvement in tensile strength than the one containing 1.0 wt% nanoparticles, due to nanoparticle-agglomeration and micro-cracks at the interface. The addition of 0.5 wt% nanoparticles significantly improved the wear resistance of Sn-based Babbitt alloy. Full article
(This article belongs to the Special Issue Novel Material and Technological Solutions in Foundry Engineering)
►▼ Show Figures

Graphical abstract

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-15
Back to TopTop