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Physical Metallurgy of Metals and Alloys

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Metals and Alloys".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 33325

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Special Issue Editors

State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
Interests: bulk metallic glasses; high-entropy alloys; titanium alloys; metallic composites; precision metal plastic forming; powder metallurgy; incremental sheet forming
Special Issues, Collections and Topics in MDPI journals
State Key Laboratory of Advanced Design and Manufacture for Vehicle Body, College of Mechanical and Vehicle Engineering, Hunan University, Changsha 410082, China
Interests: superalloys; metal cutting; composites; additive manufacturing; laser processing/cutting
Special Issues, Collections and Topics in MDPI journals
School of Mechanical Engineering and Electronic Information, China University of Geosciences, Wuhan 430074, China
Interests: microforming; ultrasonic forming; ultrasonic machining; additive manufacturing
Special Issues, Collections and Topics in MDPI journals
Key Laboratory for New Type of Functional Materials of Hebei Province, School of Materials Science and Engineering, Hebei University of Technology, Tianjin 300400, China
Interests: solidification behavior of light alloys; bulk metallic glass composites; strengthening and toughening of metals and their fatigue behavior; functional metal materials for water treatment
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Physical metallurgy is important in the design and optimization of advanced materials with superior physical and mechanical properties over their service lives via microstructural modifications and processing techniques. The goal of this Special Issue on the physical metallurgy of metals and alloys is to bring together information on the recent progress, novel technologies, advanced equipment described in our works on the design and development of advanced metals and alloys and provide guidelines/benchmarks for further research in related areas. Composites, intermetallics, and nanomaterials as well as functional materials will be also included.

Examples of some of the recent advances relating to the design, properties, and processing of advanced metals and alloys include novel material processing techniques, manufacturing methods/theories, microstructural characterization, modelling development, and advanced equipment. Conventional and nonconventional processes relating to machining, forming, laser processing, additive/subtractive manufacturing, surface modification, and the solidification of high performance alloys/metals are also included.  

Topics of papers that will be considered for publication in this Special Issue of Materials can include all the above classes of materials and the areas of physical metallurgy, process metallurgy, materials science, and processing techniques. Specific areas of interest also include titanium/nickel-based superalloys, intermetallics, advanced metallic materials, nanomaterials, metal matrix composites, functional materials, related synthesis and processing techniques, finite element modelling, statistical analysis, physical/mechanical property characterization, experimental validation, and other relevant phenomena. Full papers, short communications, and reviews are all welcome.

Dr. Pan Gong
Dr. Maojun Li
Dr. Guangchao Han
Dr. Xin Wang
Guest Editors

Manuscript Submission Information

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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

  • advanced metallic alloys
  • combinatorial alloy design
  • additive manufacturing and powder metallurgy
  • energy field-assisted machining and plastic forming technologies
  • solidification and casting
  • high-energy beam welding
  • heat treatment and surface treatment
  • microstructure-property characterization
  • simulation and modelling
  • strengthening and toughening technologies

Related Special Issue

Published Papers (24 papers)

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Research

11 pages, 2840 KiB  
Article
DSC Analysis of the Effect of Cold Deformation on the Precipitation Kinetics of a Binary Cu-Sc Alloy
by Ramona Henle, Julia Dölling, Ulrich Prahl, Gerrit Nandi and Andreas Zilly
Materials 2023, 16(9), 3462; https://doi.org/10.3390/ma16093462 - 29 Apr 2023
Cited by 1 | Viewed by 949
Abstract
The present study aimed to investigate the effect of cold deformation on the precipitation kinetics of a binary CuSc alloy containing 0.4 wt.% scandium using the experimental analysis method of differential scanning calorimetry (DSC). Non-deformed and 75% cross-section-reduced cold-rolled supersaturated specimens were tested [...] Read more.
The present study aimed to investigate the effect of cold deformation on the precipitation kinetics of a binary CuSc alloy containing 0.4 wt.% scandium using the experimental analysis method of differential scanning calorimetry (DSC). Non-deformed and 75% cross-section-reduced cold-rolled supersaturated specimens were tested in non-isothermal DSC runs at up to five different heating rates. The DSC results showed that cold rolling significantly accelerated the precipitation process in the binary alloy, leading to a decrease in the initial and peak temperatures of the exothermic reactions. The activation energies calculated with the Kissinger method indicated that the precipitation activation energy decreased with increasing cold deformation. The findings of this study provide worthy implications to further optimize the processing of Cu-Sc alloys with improved mechanical properties. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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14 pages, 10513 KiB  
Article
Numerical Prediction of Microstructure Evolution of Small-Diameter Stainless Steel Balls during Cold Skew Rolling
by Jing Zhou, Shengqiang Liu, Baoyu Wang and Hao Xu
Materials 2023, 16(8), 3246; https://doi.org/10.3390/ma16083246 - 20 Apr 2023
Cited by 1 | Viewed by 664
Abstract
The wear resistance and hardness of stainless steel (SS) balls formed by cold skew rolling are effectively improved due to the change in internal microstructure. In this study, based on the deformation mechanism of 316L stainless steel, a physical mechanism-based constitutive model was [...] Read more.
The wear resistance and hardness of stainless steel (SS) balls formed by cold skew rolling are effectively improved due to the change in internal microstructure. In this study, based on the deformation mechanism of 316L stainless steel, a physical mechanism-based constitutive model was established and implemented in a subroutine of Simufact to investigate the microstructure evolution of 316L SS balls during the cold skew rolling process. The evolution of equivalent strain, stress, dislocation density, grain size, and martensite content was studied via simulation during the steel balls’ cold skew rolling process. The corresponding skew rolling experiments of steel balls were carried out to verify the accuracy of the finite element (FE) model results. The results showed that the macro dimensional deviation of steel balls fluctuates less, and the microstructure evolution agrees well with the simulation results, which proves that the established FE model has high credibility. It shows that the FE model, coupled with multiple deformation mechanisms, provides a good prediction of the macro dimensions and internal microstructure evolution of small-diameter steel balls during cold skew rolling. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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15 pages, 6372 KiB  
Article
Numerical Simulation of Slag Entrainment by Vortex Flux during Tapping at Converter
by Chengyong Huang, Ye Sun, Wei Liu, Jingshe Li, Shufeng Yang and Jianfeng Dong
Materials 2023, 16(8), 3209; https://doi.org/10.3390/ma16083209 - 19 Apr 2023
Cited by 2 | Viewed by 873
Abstract
In order to improve the yield of steel produced in the converter and the quality of the molten steel, and to understand the distribution of the flow field in the converter and ladle during the steelmaking process, the CFD fluid simulation software Fluent [...] Read more.
In order to improve the yield of steel produced in the converter and the quality of the molten steel, and to understand the distribution of the flow field in the converter and ladle during the steelmaking process, the CFD fluid simulation software Fluent 2020 R2 was used to analyze the flow field of the converter static steelmaking process. The aperture of the steel outlet and the timing of the vortex formation under different angles were studied, as well as the disturbance level of the injection flow in the ladle molten pool. The study revealed that in the steelmaking process, the emergence of tangential vectors caused the entrainment of slag by the vortex, whereas in the later stages of steelmaking, the turbulent flow of slag disrupted the vortex, resulting in its dissipation. When the converter angle increases to 90°, 95°, 100°, and 105°, the eddy current occurrence time is 43.55 s, 66.44 s, 68.80 s, and 72.30 s, and the eddy current stabilization time is 54.10 s, 70.36 s, 70.95 s, and 74.26 s, respectively. When the converter angle is 100–105°, it is suitable to add alloy particles into the ladle molten pool. When the tapping port diameter is 220 mm, the eddy current inside the converter changes and the mass flow rate of the tapping port is “oscillating”. When the aperture of the steel outlet was 210 mm, the steelmaking time could be shortened by about 6 s without affecting the internal flow field structure of the converter. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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11 pages, 4626 KiB  
Article
On the Aging Kinetics of a Flame-Resistant AZ91D-1.5%Ca Magnesium Alloy Processed with Ultrasonic Vibration
by Inês V. Gomes, Fabrizio D’Errico, José L. Alves and Hélder Puga
Materials 2023, 16(8), 3152; https://doi.org/10.3390/ma16083152 - 17 Apr 2023
Viewed by 980
Abstract
The Mg-Al-Zn-Ca system has demonstrated excellent flame resistance and mechanical properties in the as-cast condition. However, the potential of these alloys to be heat-treated, e.g., by aging, as well as the influence of the initial microstructure on the precipitation kinetics, is yet to [...] Read more.
The Mg-Al-Zn-Ca system has demonstrated excellent flame resistance and mechanical properties in the as-cast condition. However, the potential of these alloys to be heat-treated, e.g., by aging, as well as the influence of the initial microstructure on the precipitation kinetics, is yet to be comprehensively explored. Ultrasound treatment was applied during the solidification of an AZ91D-1.5%Ca alloy to promote microstructure refinement. Samples from treated and non-treated ingots were subjected to solution treatment at 415 °C for 480 min, followed by aging at 175 °C for up to 4920 min. The results showed that the ultrasound-treated material could reach the peak-age condition in a shorter period than the non-treated one, suggesting accelerated precipitation kinetics and, thus, enhanced aging response. However, the tensile properties showed a decrease in the peak age compared to the as-cast condition, probably due to the formation of precipitates at the grain boundaries that promote the formation of microcracks and intergranular early fracture. This research shows that tailoring the material’s as-cast microstructure may positively affect its aging response, shortening the heat treatment duration, thereby making the process less expensive and more sustainable. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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13 pages, 5285 KiB  
Article
A Lightweight AlCrTiV0.5Cux High-Entropy Alloy with Excellent Corrosion Resistance
by Zhen Peng, Baowei Li, Zaibin Luo, Xuefei Chen, Yao Tang, Guannan Yang and Pan Gong
Materials 2023, 16(7), 2922; https://doi.org/10.3390/ma16072922 - 06 Apr 2023
Cited by 5 | Viewed by 1218
Abstract
Lightweight high-entropy alloys (HEAs) are a new class of low-density, high strength-to-weight ratio metallic structural material. Understanding their corrosion behavior is crucial for designing microstructures for their practical applications. This work investigates the electrochemical corrosion behavior of lightweight HEAs AlCrTiV0.5Cux [...] Read more.
Lightweight high-entropy alloys (HEAs) are a new class of low-density, high strength-to-weight ratio metallic structural material. Understanding their corrosion behavior is crucial for designing microstructures for their practical applications. This work investigates the electrochemical corrosion behavior of lightweight HEAs AlCrTiV0.5Cux (x = 0, 0.2, 0.4, 0.6, 0.8, and 1.0) in a 0.6 M NaCl solution. These HEAs were produced by vacuum arc melting. In contrast to 304L stainless steel, all of the alloys exhibited lower current density levels caused by self-corrosion, with AlCrTiV0.5 demonstrating the highest corrosion resistance (0.131 μA/cm2). Corrosion resistance decreased along with the content of copper because copper segregation accelerated local corrosion throughout the alloy. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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16 pages, 6354 KiB  
Article
A Comparative Study on Microstructural Characterization of Thick High Strength Low Alloy Steel Weld by Arc Welding and Laser Welding
by Yunxia Chen, Xiao Xu, Yanjing Liu and Haichao Cui
Materials 2023, 16(6), 2212; https://doi.org/10.3390/ma16062212 - 09 Mar 2023
Cited by 1 | Viewed by 1326
Abstract
Welding and the behavior of the weldments are important, since welding of high strength low alloy (HSLA) steels is a conventional method for manufacturing industrial parts. This work conducts a comparative investigation of microstructural characteristics and mechanical properties for joints of 16-mm-thick HSLA [...] Read more.
Welding and the behavior of the weldments are important, since welding of high strength low alloy (HSLA) steels is a conventional method for manufacturing industrial parts. This work conducts a comparative investigation of microstructural characteristics and mechanical properties for joints of 16-mm-thick HSLA Q890 steel produced by multi-layer multi-pass shielded metal arc welding (SMAW) with filler wire and single-layer autogenous laser beam welding (LBW). The mechanical properties of the welded joints were assessed in terms of tensile and impact using butt joints. The results show that tensile failure occurred in the base metal during the tensile tests for most of the trials. The ultimate tensile strength and percent elongation of the LBW welded joint (973.5 MPa and 10%) are higher than those of the SMAW joint (951 MPa and 2.9%) due to the filler filling process of the SMAW process. The Charpy impact energy of the weld metal (16.4 J and 15.1 J) is lower than that of the heat-affected zone (18.5 J and 19.5 J) in the LBW joint and the SMAW joint. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 3146 KiB  
Article
Formation of TiB2–MgAl2O4 Composites by SHS Metallurgy
by Chun-Liang Yeh and Fu-You Zheng
Materials 2023, 16(4), 1615; https://doi.org/10.3390/ma16041615 - 15 Feb 2023
Cited by 2 | Viewed by 829
Abstract
TiB2–MgAl2O4 composites were fabricated by combustion synthesis involving metallothermic reduction reactions. Thermite reagents contained Al and Mg as dual reductants and TiO2 or B2O3 as the oxidant. The reactant mixtures also comprised elemental Ti [...] Read more.
TiB2–MgAl2O4 composites were fabricated by combustion synthesis involving metallothermic reduction reactions. Thermite reagents contained Al and Mg as dual reductants and TiO2 or B2O3 as the oxidant. The reactant mixtures also comprised elemental Ti and boron, as well as a small amount of Al2O3 or MgO to serve as the combustion moderator. Four reaction systems were conducted and all of them were exothermic enough to proceed in the mode of self-propagating high-temperature synthesis (SHS). The reaction based on B2O3/Al/Mg thermite and diluted with MgO was the most exothermic, while that containing TiO2/Al/Mg thermite and Al2O3 as the diluent was the least. Depending on different thermites and diluents, the combustion front temperatures in a range from 1320 to 1720 °C, and combustion wave velocity from 3.9 to 5.7 mm/s were measured. The XRD spectra confirmed in situ formation of TiB2 and MgAl2O4. It is believed that MgAl2O4 was synthesized through a combination reaction between Al2O3 and MgO, both of which can be totally or partially produced from the metallothermic reduction of B2O3 or TiO2. The microstructure of the TiB2–MgAl2O4 composite exhibited fine TiB2 crystals surrounded by large densified MgAl2O4 grains. This study demonstrated an energy-saving and efficient route for fabricating MgAl2O4-containing composites. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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18 pages, 9876 KiB  
Article
Multipass Friction Stir Processing of Laser-Powder Bed Fusion AlSi10Mg: Microstructure and Mechanical Properties
by Akbar Heidarzadeh, Mahsa Khorshidi, Roghayeh Mohammadzadeh, Rasoul Khajeh, Mohammadreza Mofarrehi, Mousa Javidani and X.-Grant Chen
Materials 2023, 16(4), 1559; https://doi.org/10.3390/ma16041559 - 13 Feb 2023
Cited by 7 | Viewed by 1371
Abstract
The effect of multipass friction stir processing (FSP) on the microstructure and mechanical properties of an AlSi10Mg alloy produced by laser-powder bed fusion was investigated. FSP was performed at a rotational speed of 950 rpm and traverse speed of 85 mm/min. The results [...] Read more.
The effect of multipass friction stir processing (FSP) on the microstructure and mechanical properties of an AlSi10Mg alloy produced by laser-powder bed fusion was investigated. FSP was performed at a rotational speed of 950 rpm and traverse speed of 85 mm/min. The results indicated that FSP destroyed the coarse grain structure in the as-built AlSi10Mg by generating fine and equiaxed grain structures with shear texture components of A1*(111)[1¯1¯2] and A2*(111)[112¯], in addition to causing fragmentation and refinement of the Si networks. FSP reduced the tensile strength slightly but significantly improved ductility. One-pass FSP exhibited superior mechanical properties compared with the two- and three-pass scenarios. The higher strength of the one-pass sample was attributed to the strengthening mechanisms induced by the Si particles, which were grown by repeated FSP. The higher ductility of the one-pass sample was explained using the kernel and grain average misorientations. Furthermore, the post-FSP microstructural evolution and fracture behavior of the samples were discussed. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 7875 KiB  
Article
Improving the Thermal Stability of the Fine-Grained Structure in the Cu-15Ni-8Sn Alloy during Solution Treatment by the Additions of Si and Ti
by Chao Zhao, Daoxi Li, Xiaotao Liu, Minghan Sun, Zhi Wang, Zongqiang Luo and Weiwen Zhang
Materials 2023, 16(3), 1252; https://doi.org/10.3390/ma16031252 - 01 Feb 2023
Cited by 2 | Viewed by 1012
Abstract
Grain refinement has been found to be an effective method for simultaneously enhancing strength and toughness. To avoid the sharp coarsening of grains in Cu-Ni-Sn alloys during solution treatment and thereby overcoming the tradeoff between strength and ductility, this work attempted to modify [...] Read more.
Grain refinement has been found to be an effective method for simultaneously enhancing strength and toughness. To avoid the sharp coarsening of grains in Cu-Ni-Sn alloys during solution treatment and thereby overcoming the tradeoff between strength and ductility, this work attempted to modify the composition and improve the thermal stability of the fine-grained structure in Cu-Ni-Sn alloys. The grain growth behavior during a solution treatment of the Cu-15Ni-8Sn alloys with/without Si and Ti additions was systematically investigated. The result reveals that compared to the grain size of 146 μm in the based alloy (without trace additions) after solution processing at 1073 K for 2 h, the fine-grained structure with a size below 20 μm is maintained owing to the benefit from Si and Ti addition. It was observed that the addition of Si and Ti offer the inhibition effect on the dissolution of the γ phase and Ni16Si7Ti6 particles after solution treatment. The grain boundary movement is severely hindered by these two aspects: the pinning effect from these particles, and the drag effect induced by additional solute atoms. Based on the analysis of grain growth kinetics, the activation energy of grain growth is increased from 156 kJ/mol to 353 kJ/mol with the addition of Si and Ti. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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12 pages, 5020 KiB  
Article
Metallographic Mechanism of Embrittlement of 15 μm Ultrafine Quaternary Silver Alloy Bonding Wire in Chloride Ions Environment
by Jun-Ren Zhao, Fei-Yi Hung and Che-Wei Hsu
Materials 2023, 16(3), 1066; https://doi.org/10.3390/ma16031066 - 25 Jan 2023
Cited by 2 | Viewed by 986
Abstract
Chloride ions contained in the sealing compound currently used in the electronic packaging industry not only interact with intermetallic compounds but also have a serious impact on silver alloy wires. A 15 μm ultrafine quaternary silver-palladium-gold-platinum alloy wire was used in this study. [...] Read more.
Chloride ions contained in the sealing compound currently used in the electronic packaging industry not only interact with intermetallic compounds but also have a serious impact on silver alloy wires. A 15 μm ultrafine quaternary silver-palladium-gold-platinum alloy wire was used in this study. The wire and its bonding were immersed in a 60 °C saturated sodium chloride solution (chlorination experiment), and the strength and elongation before and after chlorination were measured. Finally, the fracture surface and cross-section characteristics were observed using a scanning electron microscope and focused ion microscope. The results revealed that chloride ions invade the wire along the grain boundary, and chlorides have been generated inside the cracks to weaken the strength and elongation of the wire. In addition, chloride ions invade the interface of the wire bonding to erode the aluminum substrate after immersing it for enough long time, causing galvanic corrosion, which in turn causes the bonding joint to separate from the aluminum substrate. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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17 pages, 9211 KiB  
Article
Grain Structure Formation and Texture Modification through Multi-Pass Friction Stir Processing in AlSi10Mg Alloy Produced by Laser Powder Bed Fusion
by Akbar Heidarzadeh, Mousa Javidani, Mohammadreza Mofarrehi, Pouyan Motalleb-nejad, Roghayeh Mohammadzadeh, Hamidreza Jafarian and X.-Grant Chen
Materials 2023, 16(3), 944; https://doi.org/10.3390/ma16030944 - 19 Jan 2023
Cited by 5 | Viewed by 1289
Abstract
A new strategy is proposed to modify the grain structure and crystallographic texture of laser-powder bed fusion AlSi10Mg alloy using multi-pass friction stir processing (FSP). Accordingly, 1–3 passes of FSP with 100% overlap were performed. Scanning electron microscopy and electron backscattered diffraction were [...] Read more.
A new strategy is proposed to modify the grain structure and crystallographic texture of laser-powder bed fusion AlSi10Mg alloy using multi-pass friction stir processing (FSP). Accordingly, 1–3 passes of FSP with 100% overlap were performed. Scanning electron microscopy and electron backscattered diffraction were used for microstructural characterization. Continuous dynamic recrystallization and geometric dynamic recrystallization are the governing mechanisms of grain refinement during FSP. The stir zones have bimodal grain structures containing large and fine grains. The multi-pass FSP caused a considerable increase in the volume fraction of the large-grained area in the stir zone, which contained higher values of low-angle boundaries and sharp shear texture components of B(11¯2)[110] and B¯(1¯12¯)[1¯1¯0]. The formation of low-energy grain boundaries in the stir zone and alignment of the low-energy crystallographic planes with the surface of the sample made the strategy of using multi-pass FSP a promising candidate for corrosion resistance enhancement in future studies. Moreover, the detailed evolution of the grains, texture components, grain boundaries, and Si particles is discussed. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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15 pages, 67508 KiB  
Article
Grinding Temperature and Surface Integrity of Quenched Automotive Transmission Gear during the Form Grinding Process
by Xiaoyang Jiang, Ke Liu, Yong Yan, Maojun Li, Pan Gong and Hong He
Materials 2022, 15(21), 7723; https://doi.org/10.3390/ma15217723 - 02 Nov 2022
Cited by 10 | Viewed by 1308
Abstract
Grinding burn is an undesired defect in gear machining, and a white layer is an indication of severe burn that is detrimental to gear surface performance. In this work, the influence of grinding parameters on the thickness of the white layer during form [...] Read more.
Grinding burn is an undesired defect in gear machining, and a white layer is an indication of severe burn that is detrimental to gear surface performance. In this work, the influence of grinding parameters on the thickness of the white layer during form grinding of quenched transmission gear was investigated, and the microstructure evolution and mechanism of severe burn formation were analyzed. The grinding temperature increased with the grinding depth and grinding speed, with the highest level of ~290 °C. The thickness of the white layer exceeded 100 μm when the grinding depth was 0.03 mm, and the top layer was a plastic deformation layer followed by a fine-grained martensite layer. Coarse-grained acicular martensite was found at the interface between the white layer and softened dark layer. The mechanical effect and thermal softening mainly contributed to the formation of white layer stratification. The ground surface topography showed several scratches and typical grooves; when grinding depth increased to 0.03 mm, the grinding surface roughness Sa was relatively high and reached up to ~0.60 μm, mainly owing to severe plastic deformation under grinding wheel extrusion and the thermal effect. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 4878 KiB  
Article
Versatile Medium Entropy Ti-Based Bulk Metallic Glass Composites
by Tianzeng Liu, Yanchun Zhao, Li Feng and Pan Gong
Materials 2022, 15(20), 7304; https://doi.org/10.3390/ma15207304 - 19 Oct 2022
Viewed by 928
Abstract
An ultra-strong Ti-based bulk metallic glass composite was developed via the transformation-induced plasticity (TRIP) effect to enhance both the ductility and work-hardening capability of the amorphous matrix. The functionally graded composites with a continuous gradient microstructure were obtained. It was found that the [...] Read more.
An ultra-strong Ti-based bulk metallic glass composite was developed via the transformation-induced plasticity (TRIP) effect to enhance both the ductility and work-hardening capability of the amorphous matrix. The functionally graded composites with a continuous gradient microstructure were obtained. It was found that the austenitic center possesses good plasticity and toughness. Furthermore, the amorphous surface exhibited high strength and hardness, as well as excellent wear corrosion resistance. Compared with the Ti-6Al-4V alloy, bulk metallic glass composites (BMGCs) exhibit better spontaneous passivation behavior during the potential dynamic polarization. No crystallization was observed on the friction surface, indicating their good friction-reduction and anti-wear properties. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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8 pages, 2699 KiB  
Article
Glass-Forming Ability and Corrosion Behavior of Ti-Based Amorphous Alloy Ti-Zr-Si-Fe
by Ling Bai, Ziyang Ding, Haiying Zhang and Chunxiang Cui
Materials 2022, 15(20), 7229; https://doi.org/10.3390/ma15207229 - 17 Oct 2022
Viewed by 931
Abstract
Ti-based alloy Ti75Zr11Si9Fe5 (At %) and Ti66Zr11Si15Fe5Mo3 (At %) ribbons are fabricated by a single roller spun-melt technique, according to the three empirical rules. Both alloys are found to have a large, supercooled liquid region (ΔTx) before crystallization that reaches 80–90 [...] Read more.
Ti-based alloy Ti75Zr11Si9Fe5 (At %) and Ti66Zr11Si15Fe5Mo3 (At %) ribbons are fabricated by a single roller spun-melt technique, according to the three empirical rules. Both alloys are found to have a large, supercooled liquid region (ΔTx) before crystallization that reaches 80–90 K. The results show that both alloys possess excellent glass-forming abilities. The electrochemical measurement proves both amorphous alloys possess relatively high corrosion resistance in 3 mass% NaCl solution. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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13 pages, 8787 KiB  
Article
Effect of Aging Treatment on Microstructural Evolution and Mechanical Properties of the Electron Beam Cold Hearth Melting Ti-6Al-4V Alloy
by Jiaxin Yu, Zhengpei Yin, Zhirong Huang, Shuai Zhao, Haiguang Huang, Kun Yu, Rongfeng Zhou and Han Xiao
Materials 2022, 15(20), 7122; https://doi.org/10.3390/ma15207122 - 13 Oct 2022
Cited by 8 | Viewed by 1244
Abstract
Ti-6Al-4V (Ti64 or TC4) alloy is widely used in the industrial field. However, there have been few studies of the TC4 alloy melted by electron beam cold hearth melting (EBCHM) technology. Aging treatment has a considerable influence on the secondary α-phase in titanium [...] Read more.
Ti-6Al-4V (Ti64 or TC4) alloy is widely used in the industrial field. However, there have been few studies of the TC4 alloy melted by electron beam cold hearth melting (EBCHM) technology. Aging treatment has a considerable influence on the secondary α-phase in titanium alloys. Therefore, TC4 alloy melted by EBCHM technology was investigated in this study. The effect of different aging times on the microstructural evolution and mechanical properties of titanium alloy sheets was evaluated. The results showed that, with increase in aging time, the primary α-phase enlarged and grain globularization occurred. In addition, some transformed β-phases disappeared. The strength and Vickers hardness of the heat-treated sheets decreased, while the plasticity increased with increase in aging time, indicating that the mechanical properties developed with evolution of the microstructure. After aging at 560 °C for 2 h, the properties overall were optimal. The type of fracture of the samples was ductile fracture; the dimples became larger with increase in aging time. After heat treatment, the recrystallized nucleus, substructures and HAGBs increased, while the deformed structure and LAGBs decreased. Some grains had rotated following heat treatment, indicating that anisotropy was greatly reduced. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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26 pages, 14257 KiB  
Article
Alloying Elements Effect on the Recrystallization Process in Magnesium-Rich Aluminum Alloy
by Vladimir Aryshenskii, Fedor Grechnikov, Evgenii Aryshenskii, Yaroslav Erisov, Sergey Konovalov, Maksim Tepterev and Alexander Kuzin
Materials 2022, 15(20), 7062; https://doi.org/10.3390/ma15207062 - 11 Oct 2022
Cited by 1 | Viewed by 1554
Abstract
This paper addresses the study of the complex effect of alloying elements (magnesium, manganese, copper and zirconium) on changes in magnesium-rich aluminum alloy composition, fine and coarse particle size and number, recrystallization characteristics and mechanical properties. The data obtained made it possible to [...] Read more.
This paper addresses the study of the complex effect of alloying elements (magnesium, manganese, copper and zirconium) on changes in magnesium-rich aluminum alloy composition, fine and coarse particle size and number, recrystallization characteristics and mechanical properties. The data obtained made it possible to analyze change in the chemical composition, sizes of intermetallic compounds and dispersoids depending on alloying elements content. The effect of the chemical composition on the driving force and the number of recrystallization nuclei was studied. It was established that the addition of alloying elements leads to grain refinement, including through the activation of a particle-stimulated nucleation mechanism. As a result, with Mg increase from 4 to 5%, addition of 0.5% Mn and 0.5% Cu, the grain size decreased from 72 to 15 µm. Grain refinement occurred due to an increase in the number of particle-stimulated nuclei, the number of which at minimal alloying rose from 3.47 × 1011 to 81.2 × 1011 with the maximum concentration of Mg, Mn, Cu additives. The retarding force of recrystallization, which in the original alloy was 1.57 × 10−3 N/m2, increased to 5.49 × 10−3 N/m2 at maximum alloying. The influence of copper was especially noticeable, the introduction of 0.5% increasing the retarding force of recrystallization by 2.39 × 10−3 N/m2. This is due to the fact that copper has the most significant effect on the size and number of intermetallic particles. It was established that strength increase without ductility change occurs when magnesium, manganese and copper content increases. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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14 pages, 4988 KiB  
Article
Experimental and Simulation Investigation of Nd Additions on As-Cast Microstructure and Precipitate Development in Mg–Nd System Alloys
by Xuewei Yan, Bin Su, Xuemei Yang, Qingdong Xu, Xiaopeng Zhang, Jing Wang and Zhenhua Wen
Materials 2022, 15(7), 2535; https://doi.org/10.3390/ma15072535 - 30 Mar 2022
Cited by 2 | Viewed by 1377
Abstract
The microstructure and precipitate evolution of as-cast Mg–Nd alloys with different contents of Nd was investigated via experimental and simulation methods. The research showed that the as-cast microstructure of Mg–Nd alloy consisted of α-Mg dendrites and the intermetallic phases. A metastable β [...] Read more.
The microstructure and precipitate evolution of as-cast Mg–Nd alloys with different contents of Nd was investigated via experimental and simulation methods. The research showed that the as-cast microstructure of Mg–Nd alloy consisted of α-Mg dendrites and the intermetallic phases. A metastable β phase precipitated, followed by α-Mg dendrites that could be confirmed as Mg12Nd by X-ray diffraction (XRD) analysis. The amount of β-Mg12Nd presented a rising trend with increasing Nd additions. In addition, the tertiary phase was also observed in as-cast Mg–Nd alloy when Nd content was greater than 3 wt.%, which precipitated from the oversaturated α-Mg matrix. The tertiary phase should be β1-Mg3Nd, which is also a metastable phase with a face-centered cubic lattice. However, it is a pity that the tertiary phase was not detected by the XRD technique. Moreover, an effective cellular automaton (CA) model was explored and applied to simulate the time-dependent α-Mg/β1-Mg3Nd eutectic growth. The simulated results of α-Mg/β1-Mg3Nd eutectic growth in Mg-3Nd presented that the growth of α-Mg dendrites was accompanied by the nucleation and growth of β1-Mg3Nd precipitates and eventually formed a eutectic structure. The eutectic morphologies for Mg–Nd system alloys with different Nd contents were also simulated using the proposed model, and the results revealed that α-Mg dendrite was a refinement, and the amount of α-Mg/β1-Mg3Nd eutectic was promoted, with increasing Nd content. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 2541 KiB  
Article
Improved Anti-Vulcanization and Bonding Performance of a Silver Alloy Bonding Wire by a Cathodic Passivation Treatment with Palladium
by Guannan Yang, Zhiqiang Zhou, Haide Zhang, Yu Zhang, Zhen Peng, Pan Gong, Xin Wang and Chengqiang Cui
Materials 2022, 15(7), 2355; https://doi.org/10.3390/ma15072355 - 22 Mar 2022
Cited by 3 | Viewed by 1522
Abstract
As a traditional interconnect material, silver alloy bonding wires are widely used in electronic packaging, but their propensity to vulcanize quickly has not been sufficiently addressed. The current surface anti-oxidation and anti-sulfidation treatments are often accompanied by a decline in bonding performance, which [...] Read more.
As a traditional interconnect material, silver alloy bonding wires are widely used in electronic packaging, but their propensity to vulcanize quickly has not been sufficiently addressed. The current surface anti-oxidation and anti-sulfidation treatments are often accompanied by a decline in bonding performance, which hinders the use of silver alloy bonding wires in new applications. In the present paper, we develop a new cathodic passivation treatment in a Pd-containing solution for silver bonding wires, which not only significantly improves their vulcanization resistance, but also maintains their bonding performance. The surface of the treated wires remains unaffected after vulcanization in 0.3 μg/m3 of ammonium sulfide for 60 min. Compared to a Pd-free passivation treatment, the bonding strength of the wire passivated with the Pd-containing solution improves from 0.20 to 0.27 N. XPS analysis confirms the existence of Pd on the surface of the wire. The solder ball formed an obtuse angle instead of a sharp angle on the pad, which is beneficial for bonding strength. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 4565 KiB  
Article
Metallization on Sapphire and Low-Temperature Joining with Metal Substrates
by Jiajun Fang, Qiaoxin Zhang, Zhou Luo, Wei Huang, Zhenyu Liu, Zhiwen Chen, Xueqiang Cao and Li Liu
Materials 2022, 15(5), 1783; https://doi.org/10.3390/ma15051783 - 26 Feb 2022
Cited by 2 | Viewed by 1981
Abstract
To meet the packaging requirements of sapphire in special electronic components, there is an urgent need for a joining process that can realize a good connection between sapphire and dissimilar metals at a low temperature. In this work, the surface of a sapphire [...] Read more.
To meet the packaging requirements of sapphire in special electronic components, there is an urgent need for a joining process that can realize a good connection between sapphire and dissimilar metals at a low temperature. In this work, the surface of a sapphire substrate was successfully catalytically activated and metallized by an electroless nickel plating process. Moreover, the solderability and interconnection of metallized sapphire with Sn-based solders were evaluated and investigated at 250 °C, and the wetting angle of the Sn-based solders on sapphire on sapphire without and with metallization was 125° and 51°, respectively. The interfacial microscopic morphology and element distribution in the Cu/Sn-Ag solder/sapphire solder joints were analyzed. It was found that the middle solder layer has diffused during the reflow process, inferring good adhesion between sapphire and Cu substrate with the aid of the Ni-P deposition. Thus, a sapphire welding method with a simple process suitable for practical applications is demonstrated. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 13352 KiB  
Article
Designing High Entropy Bulk Metallic Glass (HE-BMG) by Similar Element Substitution/Addition
by Hongyu Ding, Hengwei Luan, Hengtong Bu, Hongjie Xu and Kefu Yao
Materials 2022, 15(5), 1669; https://doi.org/10.3390/ma15051669 - 23 Feb 2022
Cited by 5 | Viewed by 1658
Abstract
In this paper, we report that two newly designed high entropy bulk metallic glasses (HE-BMGs), Ti20Hf20Cu20Ni20Be20 with a critical diameter of 2 mm, and Ti16.7Zr16.7Nb16.7Cu16.7Ni16.7 [...] Read more.
In this paper, we report that two newly designed high entropy bulk metallic glasses (HE-BMGs), Ti20Hf20Cu20Ni20Be20 with a critical diameter of 2 mm, and Ti16.7Zr16.7Nb16.7Cu16.7Ni16.7Be16.7 with a critical diameter of 1.5 mm, can be fabricated by copper mold casting method. These newly developed HE-BMGs exhibited a high fracture strength over 2300 MPa. The glass forming ability and atomic size distribution characteristics of the HE-BMGs are discussed in detail. Moreover, a parameter δ′ was proposed to evaluate the atomic size distribution characteristics in different HEAs. It showed that this new parameter is closely related to the degree of lattice distortion and phase selection of high-entropy alloys. Adjusting the value of δ′ parameter by similar element substitution/addition would be beneficial for designing high entropy bulk metallic glasses. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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8 pages, 3067 KiB  
Article
Effect of Radiofrequency Plasma Spheroidization Treatment on the Laser Directed Energy Deposited Properties of Low-Cost Hydrogenated-Dehydrogenated Titanium Powder
by Min Liu, Liufei Huang, Congcong Ren, Dou Wang, Qiang Li and Jinfeng Li
Materials 2022, 15(4), 1548; https://doi.org/10.3390/ma15041548 - 18 Feb 2022
Cited by 1 | Viewed by 1269
Abstract
Titanium for additive manufacturing presents a challenge in the control of costs in the fabrication of products with expanding applications compared with cast titanium. In this study, hydrogenated–dehydrogenated (HDH) titanium powder with a low cost was employed to produce spherical Ti powder using [...] Read more.
Titanium for additive manufacturing presents a challenge in the control of costs in the fabrication of products with expanding applications compared with cast titanium. In this study, hydrogenated–dehydrogenated (HDH) titanium powder with a low cost was employed to produce spherical Ti powder using the radiofrequency plasma (RF) technique. The spherical Ti powder was used as the raw material for laser directed energy deposition (LDED) to produce commercially pure titanium (CP-Ti). Microstructural analyses of the powder revealed that RF treatment, not only optimized the shape of the titanium powder, but also benefited in the removal of the residual hydride phase of the powder. Furthermore, the LDED-HDH-RF-produced samples showed an excellent combination of tensile strength and tensile ductility compared to the cast and the LDED-HDH-produced samples. Such an enhancement in the mechanical properties was attributed to the refinement of the α grain size and the dense microstructure. The present work provides an approach for LDED-produced CP-Ti to address the economic and mechanical properties of the materials, while also providing insights into the expanding application of HDH titanium powder. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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11 pages, 7015 KiB  
Article
The Microstructure and Corrosion Resistance of Fe-B-W-Mn-Al Alloy in Liquid Zinc
by Zixiang Luo, Ke Liu, Zizhen Cui, Xuemei Ouyang, Chen Zhang and Fucheng Yin
Materials 2022, 15(3), 1092; https://doi.org/10.3390/ma15031092 - 30 Jan 2022
Cited by 3 | Viewed by 2195
Abstract
The microstructure, interfacial characteristics, and corrosion resistance of Fe-W-Mn-Al-B alloys in molten zinc at 520 °C have been investigated using scanning electron microscopy (SEM), X-ray diffractometry (XRD), and electron probe micro-analysis (EPMA). The experimental results indicate that the Fe-B alloy with 11 wt.% [...] Read more.
The microstructure, interfacial characteristics, and corrosion resistance of Fe-W-Mn-Al-B alloys in molten zinc at 520 °C have been investigated using scanning electron microscopy (SEM), X-ray diffractometry (XRD), and electron probe micro-analysis (EPMA). The experimental results indicate that the Fe-B alloy with 11 wt.% W, 7 wt.% Mn, and 4 wt.% Al addition displays a lamellar eutectic microstructure and excellent corrosion resistance to molten zinc. The toughness of M2B-type borides in the hyper-eutectic Fe-4.2B-11W-7Mn-4Al alloy can be more than doubled, reaching 10.5 MPa·m1/2, by adding Mn and Al. The corrosion layer of the Fe-3.5B-11W-7Mn-4Al alloy immersed in molten zinc at 520 °C comprises Fe3AlZnx, δ-FeZn10, ζ-FeZn13, and η-Zn. The lamellar borides provide the mechanical protection for α-(Fe, Mn, Al), and the thermal stability of borides improves as the fracture toughness of the borides increases, which jointly contribute to the improvement of the corrosion resistance to the molten zinc. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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12 pages, 3905 KiB  
Article
Fabrication and Properties of Zn-3Mg-1Ti Alloy as a Potential Biodegradable Implant Material
by Shuo Zhang, Pengkai Yuan, Xin Wang, Tiebao Wang, Lichen Zhao and Chunxiang Cui
Materials 2022, 15(3), 940; https://doi.org/10.3390/ma15030940 - 26 Jan 2022
Cited by 3 | Viewed by 1622
Abstract
A Zn-3Mg-1Ti alloy was fabricated by ultrasonic treatment of Zn-Mg alloy melt using a Ti ultrasonic radiation rod. The microstructure, phase structure, mechanical properties, degradation property, and in vitro cytotoxicity were investigated systematically. The obtained Zn-3Mg-1Ti alloy is composed of the Zn, Mg [...] Read more.
A Zn-3Mg-1Ti alloy was fabricated by ultrasonic treatment of Zn-Mg alloy melt using a Ti ultrasonic radiation rod. The microstructure, phase structure, mechanical properties, degradation property, and in vitro cytotoxicity were investigated systematically. The obtained Zn-3Mg-1Ti alloy is composed of the Zn, Mg2Zn11, and TiZn16. Owing to the grain refinement and second phase reinforcement, the mechanical properties of Zn-3Mg-1Ti alloy is improved. In addition, the Zn-3Mg-1Ti alloy exhibits minimal cytotoxicity compared to pure Zn and Zn-1Ti alloy. Electrochemical tests show that the Zn-3Mg-1Ti alloy has an appropriate degradation rate in Hank’s solution. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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10 pages, 5705 KiB  
Article
Effect of Cooling Rate on the Microstructure Evolution and Mechanical Properties of Iron-Rich Al–Si Alloy
by Xiao Shen, Shuiqing Liu, Xin Wang, Chunxiang Cui, Pan Gong, Lichen Zhao, Xu Han and Zirui Li
Materials 2022, 15(2), 411; https://doi.org/10.3390/ma15020411 - 06 Jan 2022
Cited by 6 | Viewed by 1876
Abstract
The mechanical properties of iron-rich Al–Si alloy is limited by the existence of plenty of the iron-rich phase (β-Al5FeSi), whose unfavorable morphology not only splits the matrix but also causes both stress concentration and interface mismatch with the Al matrix. The [...] Read more.
The mechanical properties of iron-rich Al–Si alloy is limited by the existence of plenty of the iron-rich phase (β-Al5FeSi), whose unfavorable morphology not only splits the matrix but also causes both stress concentration and interface mismatch with the Al matrix. The effect of the cooling rate on the tensile properties of Fe-rich Al–Si alloy was studied by the melt spinning method at different rotating speeds. At the traditional casting cooling rate of ~10 K/s, the size of the needle-like β-Al5FeSi phase is about 80 μm. In contrast, the size of the β-Al5FeSi phase is reduced to 500 nm and the morphology changes to a granular morphology with the high cooling rate of ~104 K/s. With the increase of the cooling rate, the morphology of the β-Al5FeSi phase is optimized, meanwhile the tensile properties of Fe-rich Al–Si alloy are greatly improved. The improved tensile properties of the Fe-rich Al-Si alloy is attributed to the combination of Fe-rich reinforced particles and the granular silicon phase provided by the high cooling rate of the melt spinning method. Full article
(This article belongs to the Special Issue Physical Metallurgy of Metals and Alloys)
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