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Research on Heat Treatment of Advanced Metallic Materials
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Research on Heat Treatment of Advanced Metallic Materials

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

Deadline for manuscript submissions: closed (20 March 2023) | Viewed by 47743

Special Issue Editors

Prof. Dr. Guozheng Quan

E-Mail Website
Guest Editor
School of Material Science and Engineering, Chongqing University, Chongqing 400044, China
Interests: plastic mechanics modeling of alloys; multi-field and multi-scale dynamic coupling simulation of complex forming process; arc additive manufacturing and remanufacturing for components
Special Issues, Collections and Topics in MDPI journals
Dr. Chuntang Yu

E-Mail Website
Co-Guest Editor
School of Material Science and Engineering, Chongqing University of Technology, Chongqing 401320, China
Interests: nanostructure regulation of platinum-aluminum coatings; improvement of high-temperature service performance of thermal barrier coating system (TBCs); evaluation of galvanic corrosion of heterogeneous material connections; corrosion and protection of magnesium alloy
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Advanced metallic materials are the strong foundation of modern industry. It is the fact that metallic materials commonly serve as structural or functional materials for the innovative designs in lightweight, heat resistance, wearing resistance, etc. Excellent functional properties are so significant for more attractive and efficient products in term of improved properties or lower production cost. Heat treatment is a classic approach to adjust the microstructures and the corresponding properties for advanced metallic materials. Along with the rapid developments of advanced high resolution and analytical tools, and advanced heat treatment equipment and process design concept, our understanding of the structure-property relationships of advanced metallic materials have been tremendously extended. Consequently, excellent and even unthinkable serving performances have been achieved. It is always believed that the numerous innovations of heat treatment contribute to the innovative design in advanced metallic materials significantly.

This Special Issue aims at covering recent progress and new developments in relationships between the microstructure and serving properties of advanced metallic materials after heat treatment. All aspects related to heat treatment involving physical and numerical simulation, microstructural characterization, equipment, process design concept, etc. are covered. Review articles which describe the current state of the art are also welcomed.

Prof. Dr. Guozheng Quan
Dr. Chuntang Yu
Guest Editors

Manuscript Submission Information

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Keywords

  • microstructure
  • property
  • alloy
  • metal
  • heat treatment
  • physical simulation
  • numerical simulation
  • microstructural characterization
  • equipment
  • analysis

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Published Papers (25 papers)

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Research

14 pages, 7733 KiB  
Article
Feed Curves for Controlling Ring Rolling Stability in Large-Scale Flat Ring Rolling Process
by Dan Xie, Qiu-yue Ouyang, Luo-yu He and Wu-jiao Xu
Materials 2023, 16(9), 3383; https://doi.org/10.3390/ma16093383 - 26 Apr 2023
Cited by 6 | Viewed by 1566
Abstract
Due to the large wall thickness difference and serious instability in the large-scale ring rolling process, most studies on the feed curve are not suitable for a large-scale ring. The production cost of the large-scale ring is high, and if plastic instability occurs, [...] Read more.
Due to the large wall thickness difference and serious instability in the large-scale ring rolling process, most studies on the feed curve are not suitable for a large-scale ring. The production cost of the large-scale ring is high, and if plastic instability occurs, it will cause a great waste of resources. Therefore, in this study, a staged feed strategy based on the evolution of ring instability is proposed with the objective of controlling the rolling stability of a large-scale ring. Firstly, based on the law of rolling instability evolution, the rolling stage during the rolling process is divided. Secondly, the coordination of all rolling stages is proposed as a factor to design the feed curve. The feed scheme is determined using the central composite design (CCD) method, and then the established mathematical model is applied to obtain the radial feed curves of a large-scale flat ring with a 5 m diameter for different schemes. Next, the designed feed curve was submitted to finite element method (FEM) simulation. According to the FE simulation results, a rolling map for controlling roundness error, eccentricity and vibration is established. Finally, the feed curve in the stable region is input to the FE simulation and the production trial to obtain the results of roundness error, eccentricity and vibration. A comparison of the simulation and production trial results shows that they are in good agreement, which proves the reliability of the feed curve designed based on the stable rolling region in the roll map. Moreover, the machining amount for both the simulation and production trial is below the maximum machined value. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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22 pages, 7924 KiB  
Article
Characterization of Flow Behaviors by a PSO-BP Integrated Model for a Medium Carbon Alloy Steel
by Guozheng Quan, Yu Zhang, Sheng Lei and Wei Xiong
Materials 2023, 16(8), 2982; https://doi.org/10.3390/ma16082982 - 9 Apr 2023
Cited by 7 | Viewed by 1624
Abstract
In order to characterize the flow behaviors of SAE 5137H steel, isothermal compression tests at the temperatures of 1123 K, 1213 K, 1303 K, 1393 K, and 1483 K, and the strain rates of 0.01 s−1, 0.1 s−1, 1 [...] Read more.
In order to characterize the flow behaviors of SAE 5137H steel, isothermal compression tests at the temperatures of 1123 K, 1213 K, 1303 K, 1393 K, and 1483 K, and the strain rates of 0.01 s−1, 0.1 s−1, 1 s−1, and 10 s−1 were performed using a Gleeble 3500 thermo-mechanical simulator. The analysis results of true stress-strain curves show that the flow stress decreases with temperature increasing and strain rate decreasing. In order to accurately and efficiently characterize the complex flow behaviors, the intelligent learning method backpropagation–artificial neural network (BP-ANN) was combined with the particle swarm optimization (PSO), namely, the PSO-BP integrated model. Detailed comparisons of the semi-physical model with improved Arrhenius-Type, BP-ANN, and PSO-BP integrated model for the flow behaviors of SAE 5137H steel in terms of generative ability, predictive ability, and modeling efficiency were presented. The comparison results show that the PSO-BP integrated model has the best comprehensive ability, BP-ANN is the second, and semi-physical model with improved Arrhenius-Type is the lowest. It indicates that the PSO-BP integrated model can accurately describe the flow behaviors of SAE 5137H steel. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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16 pages, 5643 KiB  
Article
Forming Analysis and Heat Treatment of TC31 Titanium Alloy Component with High Ribs and Thin Webs
by Heping Deng, Wu Min, Anjun Mo, Yi Qin, Shixin Peng, Fanjiao Gongye, Shishan Li and Jie Zhou
Materials 2023, 16(7), 2860; https://doi.org/10.3390/ma16072860 - 3 Apr 2023
Cited by 1 | Viewed by 1451
Abstract
TC31 is a new type of high-temperature titanium alloy, but few researchers have studied the combination of forming and heat treatment of a component using this material. The component with high ribs and thin webs was studied by numerical simulation and trail production. [...] Read more.
TC31 is a new type of high-temperature titanium alloy, but few researchers have studied the combination of forming and heat treatment of a component using this material. The component with high ribs and thin webs was studied by numerical simulation and trail production. Based on the establishment of the finite element model, the forming process was analyzed by simulation software, and the maximum forming load of the component was 1920 kN. Ultimately, there were no folding defects of the component during the forming process. The material flow law was revealed by selecting the typical section of the component, and then the forming process was verified and the fully filled component was obtained. After that, the component was subjected to post-processing, and three heat treatment methods were designed to conduct heat treatment experiments on it (heat treatment: solution treatment and aging treatment). By analyzing the influence of three heat treatment methods on mechanical properties, the optimal heat treatment method was obtained, namely a solution treatment at 960 °C for 2.5 h and aging treatment at 610 °C for 7 h. The ultimate tensile strength, yield strength, elongation, and section shrinkage of the component through forging forming and heat treatment are higher than those of original material; meanwhile, it also indicates that the designed heat treatment has a better effect on the high-temperature mechanical properties of this titanium alloy at 650 °C than that at 450 °C. The research on the combination of the forming and heat treatment of this component provides a reference for the engineering application of high-temperature titanium alloys. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 55503 KiB  
Article
Research on Postcuring Parameters Effect on the Properties of Fiberglass-Reinforced Silicone Resin Coil Bobbin
by Hongmei He, Qiqi He, Hongchen Gao, Wei Hu and Song Xue
Materials 2023, 16(7), 2588; https://doi.org/10.3390/ma16072588 - 24 Mar 2023
Viewed by 1196
Abstract
With the growing demand for insulation parts in extreme service environments, such as nuclear power, aviation, and other related fields, fiberglass-reinforced silicone resin (FRSR) has become a popular choice due to its exceptional physical and chemical properties in high-temperature and electromagnetic working environments. [...] Read more.
With the growing demand for insulation parts in extreme service environments, such as nuclear power, aviation, and other related fields, fiberglass-reinforced silicone resin (FRSR) has become a popular choice due to its exceptional physical and chemical properties in high-temperature and electromagnetic working environments. To enhance the performance of FRSR molded parts that can adapt to more demanding extreme environments, the oven postcuring process parameters on thermal stability and mechanical properties of the bobbin were investigated. The curing behavior of FRSR was analyzed by using thermogravimetric analysis (TGA) and the differential scanning calorimetry (DSC) method, and the bobbins were manufactured based on the testing results. Subsequently, the bobbins were oven postcured at different conditions, and the heat resistance and mechanical properties were analyzed by TGA and tensile tests. The results revealed that the tensile strength of the bobbin increased by 122%, and the weight loss decreased by 0.79% at 350 °C after baking at 175 °C for 24 h. The optimal process parameters for producing bobbins to meet the criteria of nuclear installations were determined to be a molding temperature of 120 °C, molding pressure of 50 MPa, pressure holding time of 3 min, oven postcuring temperature of 175 °C, and postcuring time of 24 h. The molded products have passed the thermal aging performance test of nuclear power units. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 2417 KiB  
Article
Study of Flow Stress Models and Ductile Fracture Criteria for CHN327 Nickel-Based Superalloy
by Yufeng Xia, Wenbin Yang, Yingyan Yu, Haihao Teng and Qian Cheng
Materials 2023, 16(6), 2232; https://doi.org/10.3390/ma16062232 - 10 Mar 2023
Viewed by 1299
Abstract
The plastic deformation behavior of a CHN327 nickel-based superalloy under temperatures ranging from 600 °C to 700 °C and strain rates ranging from 0.001 to 0.1 s−1 was investigated using uniaxial high-temperature tensile tests. The stress–strain curves obtained by the tests showed [...] Read more.
The plastic deformation behavior of a CHN327 nickel-based superalloy under temperatures ranging from 600 °C to 700 °C and strain rates ranging from 0.001 to 0.1 s−1 was investigated using uniaxial high-temperature tensile tests. The stress–strain curves obtained by the tests showed that the maximum stress decreased as the temperature increased, while it increased as the strain rate increased. Based on the extensive data obtained in the experiment, three constitutive models (Hollomon, Swift, and the modified Voce equation) were employed to predict the constitutive relation. It was found that the modified Voce equation had the highest correlation coefficient and the best prediction accuracy. Thereafter, in order to predict the fracture of CHN327 during high-temperature tensile deformation, five ductile fracture criteria (Freudenthal, C&L, Brozzo, Ayada, and the R&T model), and the modified Voce equation obtained were incorporated into the finite element software (DEFORM). According to the results, except for the C&L and Brozzo models, all of the other ductile fracture criteria (DFCs) were suitable for predicting the damage distribution of the CHN327 alloy in tensile tests. For all of the DFCs considered, the R&T model provided the most accurate predictions, whose mean error was only 8.9%, far less than the values that other models predicted. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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17 pages, 9138 KiB  
Article
Study on Hot Tensile Deformation Behavior and Hot Stamping Process of GH3625 Superalloy Sheet
by Shixin Peng, Jie Zhou, Jie Peng, Heping Deng, Fanjiao Gongye and Jiansheng Zhang
Materials 2023, 16(5), 1927; https://doi.org/10.3390/ma16051927 - 25 Feb 2023
Cited by 3 | Viewed by 1427
Abstract
Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800–1050 °C and strain rates of 0.001, 0.01, 0.1, 1, and 10 s−1 on a Gleeble-3500 metallurgical processes simulator. The effect of temperature and holding time on [...] Read more.
Hot tensile tests of the GH3625 superalloy were carried out under the temperature range of 800–1050 °C and strain rates of 0.001, 0.01, 0.1, 1, and 10 s−1 on a Gleeble-3500 metallurgical processes simulator. The effect of temperature and holding time on grain growth was investigated to determine the proper heating schedule of the GH3625 sheet in hot stamping. The flow behavior of the GH3625 superalloy sheet was analyzed in detail. The work hardening model (WHM) and the modified Arrhenius model, considering the deviation degree R (R-MAM), were constructed to predict the stress of flow curves. The results showed that WHM and R-MAM have good prediction accuracy by evaluating the correlation coefficient (R) and the average absolute relative error (AARE). Additionally, the plasticity of the GH3625 sheet at elevated temperature drops with the increasing temperature and decreasing strain rate. The best deformation condition of the GH3625 sheet in the hot stamping is in the range of 800~850 °C and 0.1~10 s−1. Finally, a hot stamped part of the GH3625 superalloy was produced successfully, which had higher tensile strength and yield strength than the as-received sheet. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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14 pages, 6130 KiB  
Article
Study on the Removal of Oxide Scale Formed on 300 M Steel Special-Shaped Hot Forging Surfaces during Heating at Elevated Temperature by a High-Pressure Water Descaling Process
by Fanjiao Gongye, Jie Zhou, Jie Peng, Haicheng Zhang, Shixin Peng, Shishan Li and Heping Deng
Materials 2023, 16(4), 1745; https://doi.org/10.3390/ma16041745 - 20 Feb 2023
Cited by 7 | Viewed by 1971
Abstract
Numerical simulations and experiments were utilized to study the removal of oxide scale formed on 300 M steel special-shaped hot forging surfaces during heating at elevated temperature by a high-pressure water descaling process. Specifically, the experimental setup of the special-shaped hot forging was [...] Read more.
Numerical simulations and experiments were utilized to study the removal of oxide scale formed on 300 M steel special-shaped hot forging surfaces during heating at elevated temperature by a high-pressure water descaling process. Specifically, the experimental setup of the special-shaped hot forging was designed and manufactured according to the descaling parameters and simulation results obtained from the hot rolling process. The force states of three typical hot forging surfaces impinged by high-pressure water jets were analyzed. Moreover, the mechanism of the high-pressure water descaling process was proposed based on the research results. The numerical simulations and experimental results revealed that the velocity distribution of the high-pressure water jets is relatively different in various areas of the special-shaped hot forging surfaces. Therefore, the descaling performance is synergistically influenced by the velocity of the high-pressure water jet and the shape of the special-shaped hot forging. Given a certain spray pressure, the value of impact force Fi plays a significant role in the descaling of the typical hot forging. The larger the value of Fi on the typical hot forging surface, the easier it is to remove the oxide scale, and vice versa. Accordingly, the difficulty of removing the oxide scale formed on the 300 M steel special-shaped hot forging surfaces during heating at elevated temperature by a high-pressure water descaling process is in the following order: plane surface < convex surface < concave surface. Additionally, only the inner-layer FeO of the oxide scale remained after the high-pressure water descaling process due to the appearance of FeO-Fe2SiO4 eutectic in the FeO layer. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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11 pages, 4110 KiB  
Article
Understanding of Excellent Mechanical Performance of 304L Manufactured by Optimal Selective Laser Melting (SLM) Conditions
by Yaxin Ma, Yifei Gao, Lei Zhao, Hong Zhang, Dongling Li, Lixia Yang and Chuntang Yu
Materials 2023, 16(4), 1661; https://doi.org/10.3390/ma16041661 - 16 Feb 2023
Cited by 2 | Viewed by 1630
Abstract
The optimal SLM conditions of 304L stainless steel were obtained by single factor and orthogonal tests. Results indicated that the optimal hardness (75 HRB) and Relative Density (RD 99.24%) could be obtained when the laser output power was 190 W, the scanning distance [...] Read more.
The optimal SLM conditions of 304L stainless steel were obtained by single factor and orthogonal tests. Results indicated that the optimal hardness (75 HRB) and Relative Density (RD 99.24%) could be obtained when the laser output power was 190 W, the scanning distance was 0.09 mm and the scanning speed was 800 mm/s. The microstructure of fish scales was uniform and compact with a few pores in the optimal sample. The fine particles were randomly distributed near the edge of the molten pool, and some preferred granular columnar crystal structures were formed. Abundant entanglement dislocations were observed between cell structures, forming dislocation clusters. Spherical nano-precipitates, rich in Si, Mn, and O, were also observed near cell structures. The mechanical properties of the specimens were highly anisotropic, and there were obvious necking and ductility at the tensile fracture. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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11 pages, 7232 KiB  
Article
Microstructure Evolution and Enhanced Hot Workability of TiC/Ti-6Al-4V Composites Fabricated by Melt Hydrogenation
by Xuan Wang, Siyu Chen, Yingmei Tan, Longhui Yao, Liang Wang, Yanqing Su and Jingjie Guo
Materials 2022, 15(24), 8884; https://doi.org/10.3390/ma15248884 - 12 Dec 2022
Cited by 3 | Viewed by 1619
Abstract
Improving the hot workability and reducing the processing cost are critical steps to expanding the application of TiC/Ti-6Al-4V composites. This study employed melt hydrogenation to fabricate TiC/Ti-6Al-4V composites under a mixed atmosphere of hydrogen and argon. Experimental results indicated that hydrogen had an [...] Read more.
Improving the hot workability and reducing the processing cost are critical steps to expanding the application of TiC/Ti-6Al-4V composites. This study employed melt hydrogenation to fabricate TiC/Ti-6Al-4V composites under a mixed atmosphere of hydrogen and argon. Experimental results indicated that hydrogen had an obvious influence on the growth and morphology of eutectic TiC particles, and the size of eutectic TiC and primary β grains was significantly increased. As a result, large-sized eutectic TiC was distributed along the grain boundaries of primary β grains. Hot compression results showed that the peak flowing stress of composites was reduced by hydrogen, which resulted in an improvement of hot workability, especially in the (α + β) phase region, and the best results were obtained at 900 °C/0.01 s−1, at which the peak stress decreased from 241 ± 9 to 190 ± 8 MPa (a decrease of 21.2%). Inspection of the microstructure after hot compression showed that hydrogen improved the proportion of DRX grains from ~62.7% to ~83.2%, and hydrogen also decreased the density of dislocations, which were attributed to hydrogen accelerating atomic diffusion. Enhanced hot workability resulted from hydrogen atoms decreasing the atomic bonding force of the titanium matrix, hydrogen reducing the β/(α + β) transition temperature, the higher proportion of DRX, and the higher mobility of dislocations. It is expected that the findings of this study may support the development of a simple and efficient method to reduce the processing cost of TiC/Ti-6Al-4V composites. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 7458 KiB  
Article
Gradient Structure Design and Welding-Hammering Hybrid Remanufacturing Process of Continuous Casting Rollers
by Jiansheng Zhang, Guiqian Xiao, Jie Peng, Yingyan Yu and Jie Zhou
Materials 2022, 15(23), 8588; https://doi.org/10.3390/ma15238588 - 1 Dec 2022
Cited by 1 | Viewed by 1570
Abstract
To improve the service life and reduce the repair cost of continuous casting rollers, a new welding-hammering hybrid remanufacturing process in which the roller was designed with a gradient structure was proposed, and corresponding equipment was developed. First, the failure modes and their [...] Read more.
To improve the service life and reduce the repair cost of continuous casting rollers, a new welding-hammering hybrid remanufacturing process in which the roller was designed with a gradient structure was proposed, and corresponding equipment was developed. First, the failure modes and their causes for a continuous casting roller were analyzed by numerical simulation. The cyclic tension–compression shear stress, cyclic tension–compression normal stress, thermal cycle, and highly corrosive environment caused fatigue cracking and overall peeling of the roller surface. Second, the gradient structure composed of a base layer, transition layer, and strengthened layer of a continuous casting roller was designed, and materials for each layer were selected according to their different service conditions. Third, novel equipment for continuous welding-hammering composite remanufacturing was developed, and the optimized process parameters were obtained through welding experiments. Finally, an application test was carried out; the microscopic analysis showed that refined grains, fewer welding defects, and better surface toughness were obtained. Compared with traditional remanufacturing processes without hammering, the welding-hammering hybrid process achieved a forged structure instead of as-cast structure, which significantly improved the service life of the continuous casting roller by about 100%. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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10 pages, 2479 KiB  
Article
Effects of Solution Treatment on Damping Capacities of Binary Mg-X (X = Ga and Er) Alloys
by Xiaoyang Dong, Jinxing Wang, Zichuan Wang, Xiyu Wang, Cong Dang, Zhicheng Wan, Yi Zou, Jingfeng Wang and Fusheng Pan
Materials 2022, 15(22), 8172; https://doi.org/10.3390/ma15228172 - 17 Nov 2022
Viewed by 1572
Abstract
Designing new materials for vibration and noise reduction that are lightweight is of great significance for industrial development. Magnesium (Mg) alloy is considered one of the best damping metal structural materials because of its low density, high specific strength, good energy storage characteristics [...] Read more.
Designing new materials for vibration and noise reduction that are lightweight is of great significance for industrial development. Magnesium (Mg) alloy is considered one of the best damping metal structural materials because of its low density, high specific strength, good energy storage characteristics and rich resources. Solution atoms have an important effect on the damping capacities of Mg alloys, but the relevant laws have not been completely clarified. In this work, two kinds of alloying elements (Ga and Er) with various atomic sizes were selected to study the metallographic structure and damping capacities of binary Mg-X (X = Ga and Er) alloys in the as-cast and solid solution states, respectively. Solution treatment can improve the damping capacities of binary Mg-X (X = Ga and Er) alloys, and the damping mechanisms of the two solid solution alloys are consistent with the G-L damping mechanism. The influence of alloy elements with different atomic sizes on damping capacities is also different. This influence is due to the various radii of solute atoms and Mg atoms which can result in different degrees of lattice distortion. This work provides a research basis for development and design of high-performance damping Mg alloy materials. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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12 pages, 9708 KiB  
Article
Evaluation of Different Tools of Precision Finishing for Sun Gear with Inner-Outer Tooth Shapes
by Qiang Liang, Xianming Zhang, Yunqi Liu, Jie Zhou and Zuofa Liu
Materials 2022, 15(22), 8081; https://doi.org/10.3390/ma15228081 - 15 Nov 2022
Viewed by 1450
Abstract
Aiming at the technical difficulty of poor teeth accuracy of the extruded sun gears, an innovative precision finishing approach was developed as the subsequent process of producing high-quality sun gears, and three finishing tools were designed, namely mandrel with gap, mandrel without gap [...] Read more.
Aiming at the technical difficulty of poor teeth accuracy of the extruded sun gears, an innovative precision finishing approach was developed as the subsequent process of producing high-quality sun gears, and three finishing tools were designed, namely mandrel with gap, mandrel without gap and interference mandrel. A finite element prediction method was proposed by using the post-processing toolbox of DEFORM software to study the distribution laws of outer and inner teeth deviations of the reshaped sun gear. Moreover, the effects of various precision finishing tools on the formability of sun gear (such as tooth deformation, tool stress and tooth accuracy) were investigated. The results show that the tooth accuracy class of the reshaped outer teeth in profile and helix were seventh and eighth, respectively, and the total M-value error of the inner teeth was decreased to 72.3 μm and the reduction ratio was 73.8% by adopting the interference mandrel, which indicates that the finishing effect of the interference mandrel was better than that of mandrels for both with gap and without gap, and the forming accuracy of the finished teeth could be considerably improved. Therefore, the interference mandrel can be recommended as the optimum finishing tool in the manufacture of precision sun gears. The simulated results were in good agreement with experimental ones within a maximum error of 14.4%, which proves the practicability of the sizing approach and the dependability of the finite element prediction method. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 10666 KiB  
Article
Path Generation Strategy and Wire Arc Additive Manufacturing of Large Aviation Die with Complex Gradient Structure
by Jiansheng Zhang, Guiqian Xiao, Jie Peng, Yingyan Yu and Jie Zhou
Materials 2022, 15(17), 6115; https://doi.org/10.3390/ma15176115 - 2 Sep 2022
Cited by 4 | Viewed by 1797
Abstract
To realize automatic wire arc additive manufacturing (WAAM) of a large aviation die with a complex gradient structure, a new contour-parallel path generation strategy was proposed and practically applied. First, the planar curve was defined as a vertical slice of a higher-dimensional surface [...] Read more.
To realize automatic wire arc additive manufacturing (WAAM) of a large aviation die with a complex gradient structure, a new contour-parallel path generation strategy was proposed and practically applied. First, the planar curve was defined as a vertical slice of a higher-dimensional surface and a partial differential equation describing boundary evolution was derived to calculate the surface. The improved Finite Element Method (FEM) and Finite Difference Method (FDM) were used to solve this partial differential equation. Second, a cross section of a large aviation die was used to test the path-generation algorithms. The results show that FEM has a faster solving speed than FDM under the same solving accuracy because the solving domain of FEM mesh was greatly reduced and the boundary mesh could be refined. Third, the die was divided into three layers: base layer, transition layer (Fe-based material) and strengthening layer (Co-based material) according to the difference of the temperature and stress field, and corresponding WAAM process parameters has been discussed. The optimum welding parameters are obtained as follows: voltage is 28 V, wire feeding speed is 8000 mm/min and welding speed is 450 mm/min. Finally, the path generation strategy was practically applied to the remanufacture of the large aircraft landing gear die with a three-layer structure. The application test on aircraft landing gear dies justified the effectiveness of the algorithms and strategy proposed in this paper, which significantly improved the efficiency of the WAAM process and the service life of large aviation dies with complex gradient structures. The microstructure of the fusion zone shows that the base metal and welding material can be fully integrated into the welding process. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 7869 KiB  
Article
Influence of Surfacing Fe-Based Alloy Layers on Wire Arc Additive Manufactured Ni-Based Superalloys Material on Its Microstructure and Wear Properties
by Yingyan Yu, Zhiyuan Qu, Jiansheng Zhang and Jie Zhou
Materials 2022, 15(17), 6020; https://doi.org/10.3390/ma15176020 - 31 Aug 2022
Cited by 2 | Viewed by 1606
Abstract
Wire arc additively manufactured (WAAM) Ni-based materials have good properties but are costly and hard to cut, leading to difficulties in machining after welding and wasting the materials. To overcome these shortcomings, this work proposes a method of surfacing Fe-based alloy layers on [...] Read more.
Wire arc additively manufactured (WAAM) Ni-based materials have good properties but are costly and hard to cut, leading to difficulties in machining after welding and wasting the materials. To overcome these shortcomings, this work proposes a method of surfacing Fe-based alloy layers on WAAM Ni-based material. The effect of this method on the microstructure and wear properties of WAAM Ni-based materials is discussed. In this work, a Fe-based alloy (JX103) was welded as the last layers of the WAAM Ni-based superalloy (JX201) material. The hardness, microstructure, and wear behavior of the material with different residual Fe-based materials were tested and analyzed. Our results indicate that the surface hardness was smoothly increased from HV350 to HV400 by overlaying Fe-based alloy layers. Microstructure analysis shows that γ-Fe gradually disappears, and the carbide form changes from WAAM Ni-based superalloys to Fe-based alloys. In the fusion boundary, the occurrence of cellular dendritic growth, a type -Ⅱ boundary, and low dilution indicate good crack resistance and good connection performance between these two materials. The wear test showed that the wear resistance of JX201 was decreased by changing the last layer to JX103. However, as the residual thickness of JX103 decreased, the influence gradually reduced. Meanwhile, the wear mechanism changed from severe abrasive and adhesive wear to light abrasive wear. When the thickness is less than 0.5 mm, the wear weight per minute is at the same level as the sample without JX103. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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19 pages, 39705 KiB  
Article
Microstructural Evolution and Hardness Responses of 7050 Al Alloy during Processing
by Yuting Zhou, Jie Zhou, Xinrui Xiao, Shishan Li, Mingliang Cui, Peng Zhang, Shuai Long and Jiansheng Zhang
Materials 2022, 15(16), 5629; https://doi.org/10.3390/ma15165629 - 16 Aug 2022
Cited by 7 | Viewed by 1545
Abstract
The thermal-mechanical process (TMP) plays an important role in the industrial production of 7050 Al alloys for aircraft components. In this work, the microstructural evolution and influence on hardness of a 7050 alloy ingot, during the process from preheating, deformation and cooling to [...] Read more.
The thermal-mechanical process (TMP) plays an important role in the industrial production of 7050 Al alloys for aircraft components. In this work, the microstructural evolution and influence on hardness of a 7050 alloy ingot, during the process from preheating, deformation and cooling to final heat treatment, have been investigated considering the effect of temperature and the post-deformation cooling path. The results showed that an increasing temperature and decreasing cooling rate during TMP can lead to enhanced hardness of the alloy after heat treatment. Moreover, the variation of recrystallization before and after heat treatment was strongly dependent on the cooling path after deformation. Finally, this study provided a general understanding on the relationship between microstructural evolution and harness of the 7050 alloy. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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26 pages, 16689 KiB  
Article
Description of Dynamic Recrystallization Behaviors and Grain Evolution Mechanisms during the Hot Forming Process for SAE 5137H Steel
by Yu-Qing Zhang, Guo-Zheng Quan, Sheng Lei, Jiang Zhao and Wei Xiong
Materials 2022, 15(16), 5593; https://doi.org/10.3390/ma15165593 - 15 Aug 2022
Cited by 4 | Viewed by 1640
Abstract
Describing the dynamic recrystallization (DRX) behaviors and grain evolution mechanisms in the hot forming process contributes to controlling microstructures and enhancing mechanical properties of materials. Here, the isothermal compression experiments for SAE 5137H steel were conducted under temperatures of 1123–1483 K and strain [...] Read more.
Describing the dynamic recrystallization (DRX) behaviors and grain evolution mechanisms in the hot forming process contributes to controlling microstructures and enhancing mechanical properties of materials. Here, the isothermal compression experiments for SAE 5137H steel were conducted under temperatures of 1123–1483 K and strain rates of 0.01–10 s−1. The DRX kinetics models, including DRX volume fraction and grain size models, and the meso-scale cellular automaton (CA) models, were established based on the obtained true stress–strain curves and microstructure observation results. In order to dynamically reveal DRX behaviors and grain morphology evolution, a multi-field and multi-scale coupling finite element (FE) model for the hot compression process was developed by embedding the solved DRX kinetics models and CA models. Results show that the DRX volume fraction and grain size increase with temperature increasing and strain rate decreasing. The DRX grains are easier to nucleate at the initial grain boundaries. As strain increases, DRX grains grow up by devouring the matrix grains until DRX occurs completely. The microstructures after compression are composed of equiaxed DRX grains. Finally, the comparisons of grain size between experimental results and simulation results were performed. The mean relative errors between experimental results and predicted results from DRX kinetics models, and between experimental results and predicted results from CA models, were evaluated as 6.5% and 6.0%, respectively. It proves that the developed FE model can well describe the microstructure evolution in the hot deformation process of SAE 5137H steel. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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15 pages, 7680 KiB  
Article
Quantitative Distribution Characterization and Correlation Study of Composition, Structure and Hardness of Rim Region in Railway Wheel
by Dongling Li, Haizhou Wang, Xuejing Shen, Shuangping Lin, Haozhou Feng, Ya Peng, Fan Jiang and Xuefan Zhou
Materials 2022, 15(14), 4762; https://doi.org/10.3390/ma15144762 - 7 Jul 2022
Cited by 1 | Viewed by 1570
Abstract
The railway wheel is the key component of high-speed railway train. To assure the safety in service, higher requirements are put forward in this study for the composition, microstructure uniformity, and comprehensive properties of wheel materials. In this paper, the high throughput quantitative [...] Read more.
The railway wheel is the key component of high-speed railway train. To assure the safety in service, higher requirements are put forward in this study for the composition, microstructure uniformity, and comprehensive properties of wheel materials. In this paper, the high throughput quantitative distribution characterization methods of composition, microstructure, inclusions and Vickers hardness of high-speed railway wheel materials based on the spark source original position analysis technique, high throughput scanning electron microscope (SEM) combined with image batch processing technology, and automatic two-dimensional quantitative distribution analysis technique of inclusions and micro hardness have been studied. The distribution trend of the content of nine elements, size and quantity of sulfides and oxides, ferrite area fraction, and Vickers hardness from the wheel tread surface to the radial depth of about 50 mm below the surface has been discussed. The influence of inclusions distribution on the element segregation and the effect of rim-chilling process with different water spraying angle on the distribution of microstructure and micro hardness have been investigated. It was found that unsynchronized cooling on both sides of the rim altered the phase behavior of ferrite and pearlite and obvious inhomogeneity distribution of ferrite appeared, which led to the asymmetrical Vickers hardness in areas near or away from the flange. Based on the quantitative characterization of area fraction and micro hardness on the same location of wheel rim, a statistical mapping relationship between ferrite area fraction and Vickers hardness was established. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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11 pages, 5166 KiB  
Article
Optimization of Process Parameters and Analysis of Microstructure and Properties of 18Ni300 by Selective Laser Melting
by Yaxin Ma, Yifei Gao, Lei Zhao, Dongling Li and Zhengxing Men
Materials 2022, 15(14), 4757; https://doi.org/10.3390/ma15144757 - 7 Jul 2022
Cited by 9 | Viewed by 1916
Abstract
In this research, we studied the influence of process parameters on the quality of selective laser melting of 18Ni300 maraging steel. The effects of laser power and scanning speed on the relative density and hardness of 18Ni300 were studied by single-factor experiment and [...] Read more.
In this research, we studied the influence of process parameters on the quality of selective laser melting of 18Ni300 maraging steel. The effects of laser power and scanning speed on the relative density and hardness of 18Ni300 were studied by single-factor experiment and the orthogonal experimental method. The relative optimal process parameters of 18Ni300 were obtained when the layer thickness was 0.03 mm, and the hatch space was 0.1 mm. The microstructures and mechanical properties of the samples formed under different process parameters were characterized. The results showed that the optimal hardness and relative density of the sample were 44.7 HRC and 99.98% when the laser power was 230 W and the scanning speed was 1100 mm/s, respectively; the microstructure of the material was uniform and dense, exhibiting few pores. Some columnar crystals appeared along the boundary of the molten pool due to vertical epitaxial growth. The orientation of fine grains at the boundary of the molten pool was random, and some coarse columnar crystals in the molten pool exhibited a certain orientational preference along the <001> orientation. In the case of optimal process parameters, the SLM-formed 18Ni300 was composed of 99.5% martensite and 0.5% retained austenite; the indentation hardness was distributed in the range of 3.2–5 GPa. The indentation modulus was between 142.8–223.4 GPa, exhibiting stronger fluctuations than the indentation hardness. The sample’s mechanical properties showed obvious anisotropy, while the tensile fracture characteristics exhibited necking. The tensile fracture morphology was ductile, and large equiaxed dimples and holes could be observed in the fiber area, accompanied by tearing characteristics. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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18 pages, 6927 KiB  
Article
Experimental and Simulation Study for the Influence of Thermal Pre-Deformation on Subsequent Aging Precipitation Kinetics of Al-Zn-Mg-Cu Alloy
by Qian Sun, Sha Yu, Hong Wang, Huijuan Ma, Huanhuan Li and Zhili Hu
Materials 2022, 15(13), 4634; https://doi.org/10.3390/ma15134634 - 1 Jul 2022
Cited by 5 | Viewed by 2001
Abstract
Deformation and heat treatment are important means to strengthen aluminum alloys. However, the influence mechanism of pre-strain on aging precipitation kinetics and its effect on mechanical properties are still not clear. In this work, uniaxial isothermal tensile tests with different strains and artificial [...] Read more.
Deformation and heat treatment are important means to strengthen aluminum alloys. However, the influence mechanism of pre-strain on aging precipitation kinetics and its effect on mechanical properties are still not clear. In this work, uniaxial isothermal tensile tests with different strains and artificial aging treatments for Al-Zn-Mg-Cu alloys have been carried out. Then, a model describing the precipitates kinetic behavior has been developed to investigate the effect of thermal pre-strain on subsequent aging precipitation kinetics and peak aging microhardness based on the microstructure characterization by TEM, SAXS and XRD tests. In addition, the role of dislocations on the aging precipitation kinetics is also explored. The experimental results show that the peak aging microhardness of the Al-Zn-Mg-Cu alloy reveals a tendency to decrease and increase and then the peak aging time firstly decreases and then keeps almost constant with the increase in the strain. The calculations demonstrate that the precipitate average size almost remains unchanged, while the precipitate volume fraction decreases and then increases with the increase in strain, which is consistent with the change in peak aging microhardness. It also indicates that dislocations can promote precipitate nucleation and growth, while the actual effect depends on the dislocation density, which is closely dependent on the pre-deformation condition, especially for the precipitate nucleation. In particular, when the dislocation density after thermal pre-deformation is not enough, it will slightly inhibit precipitate nucleation but promote precipitate growth, which could shorten the peak aging time, with the peak aging strength being guaranteed. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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15 pages, 7943 KiB  
Article
Influence of Post-Bond Heat Treatment on Microstructure and Creep Behavior of the Brazed Single-Crystal Nickel Superalloy
by Xingyu Hou, Shiyang Wang, Keqiang Qiu, Yuan Sun, Yanhong Yang and Yizhou Zhou
Materials 2022, 15(12), 4053; https://doi.org/10.3390/ma15124053 - 7 Jun 2022
Cited by 5 | Viewed by 1972
Abstract
Post-bond heat treatment (PBHT) is an effective way to improve the bonding quality of a brazed joint. Herein, brazing of a nickel-based single crystal superalloy is carried out using a Ni-Cr-Co-B-Si-Al-Ti-W-Mo filler alloy, and the microstructure and creep property of the brazed joint [...] Read more.
Post-bond heat treatment (PBHT) is an effective way to improve the bonding quality of a brazed joint. Herein, brazing of a nickel-based single crystal superalloy is carried out using a Ni-Cr-Co-B-Si-Al-Ti-W-Mo filler alloy, and the microstructure and creep property of the brazed joint are systematically investigated using scanning electron microscopy (SEM), Thermo-Calc software, an electron probe micro-analyzer (EPMA), X-ray diffractometer, confocal scanning laser microscope (CSLM), and transmission electron microscopy (TEM). The results reveal that the as-prepared joint only consists of an isothermally solidified zone (ISZ) and an athermally solidified zone (ASZ), where the cubic γ′ phase is observed in the ISZ, and skeleton-like M3B2, γ + γ′ eutectic and reticular G phases are observed in the ASZ. Furthermore, the γ + γ′ eutectic and G phases disappear and the M3B2 alters from a skeleton-like to block-like shape in the ASZ after PBHT. Meanwhile, some lath-like M3B2 phases are precipitated at the edge of the ISZ and several M3B2 phases are precipitated in the base metal, forming a new zone in the brazed joint, namely at the diffusion affected zone (DAZ). Owing to the removal of low melting point eutectics from the as-prepared joint, the creep life also increases from 188 h to 243 h after PBHT. The current work provides a method for the optimization of brazed joints based on the Ni-based single crystal superalloy. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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12 pages, 3029 KiB  
Article
Optimization of the Heat Dissipation Performance of a Lithium-Ion Battery Thermal Management System with CPCM/Liquid Cooling
by Xiaoping Zeng, Zhengxing Men, Fang Deng and Cheng Chen
Materials 2022, 15(11), 3835; https://doi.org/10.3390/ma15113835 - 27 May 2022
Cited by 8 | Viewed by 2476
Abstract
In view of the harsh conditions of rapid charging and discharging of electric vehicles, a hybrid lithium-ion battery thermal management system combining composite phase change material (PCM) with liquid cooling was proposed. Based on the numerical heat transfer model, a simulation experiment for [...] Read more.
In view of the harsh conditions of rapid charging and discharging of electric vehicles, a hybrid lithium-ion battery thermal management system combining composite phase change material (PCM) with liquid cooling was proposed. Based on the numerical heat transfer model, a simulation experiment for the battery thermal management system was carried out. Taking the maximum temperature and temperature difference of the battery module as the objectives, the effects of PCM thickness, the liquid flow rate and the cross-sectional area of the liquid channel on the temperature of the battery module were analyzed using response surface methodology (RSM). The results show that 31 groups of candidate parameter combinations can be obtained through response surface analysis, and phase change material (PCM) thickness should be minimized in order to improve space utilization in the battery module. The optimal parameter combination is a flow rate of 0.4 m/s and a PCM thickness of 5.58 mm, with the cross-sectional area of the liquid channel as 3.35 mm2. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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13 pages, 5347 KiB  
Article
Effect of Annealing Process on the Microstructure and Texture of Cold-Rolled High-Purity Al-0.5%Cu Plates
by Kuiwen Yuan, Jiaxin Chen, Dan Yang and Zhiqing Zhang
Materials 2022, 15(10), 3489; https://doi.org/10.3390/ma15103489 - 12 May 2022
Cited by 2 | Viewed by 1913
Abstract
As a kind of typical high stacking fault energy materials, recrystallization behavior of high purity Al-0.5%Cu alloy is significantly influenced by the annealing process. In this study, different heating rate, target temperature, and holding time were discovered to have profound impact on the [...] Read more.
As a kind of typical high stacking fault energy materials, recrystallization behavior of high purity Al-0.5%Cu alloy is significantly influenced by the annealing process. In this study, different heating rate, target temperature, and holding time were discovered to have profound impact on the microstructures and textures of Al-0.5%Cu plates. Electron backscatter diffraction (EBSD), scanning electron microscope (SEM), and X-ray diffraction (XRD) were utilized for analyzing the evolution of the microstructure and texture in the subsequent microstructural characterization. Vickers hardness tests were employed for measuring hardness of specimens. The results showed that no obvious recrystallization was observed at lower temperature and the composition of texture influenced by rising temperature, heating rate affected initial recrystallization temperature, grain size, and strength of textures. After recrystallizing completely, the size of microstructures and the distribution of textures had little change with the extension of holding time. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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22 pages, 15925 KiB  
Article
Response Surface of Speed-Loading Path to Grain Refinement during Current-Heating Compression at SAE 5137H Steel
by Guo-Zheng Quan, Kun Yang, Yan-Ze Yu, Xue Sheng, Zhi-Hang Wen and Chao-Long Lu
Materials 2022, 15(10), 3484; https://doi.org/10.3390/ma15103484 - 12 May 2022
Cited by 1 | Viewed by 1437
Abstract
In thermal deformation of materials, grain refinement induced by dynamic recrystallization (DRX) is often pursued to obtain excellent mechanical properties. Here, the thermal deformation behaviors of SAE 5137H steel were investigated and characterized at temperature and strain rate range of 1123–1483 K and [...] Read more.
In thermal deformation of materials, grain refinement induced by dynamic recrystallization (DRX) is often pursued to obtain excellent mechanical properties. Here, the thermal deformation behaviors of SAE 5137H steel were investigated and characterized at temperature and strain rate range of 1123–1483 K and 0.01–10 s−1. Meanwhile, a design approach in speed-loading paths for grain refinement during current-heating compression was proposed, and these paths are linked to a typical three-dimensional (3D) response surface. Depending on the acquired stress–strain curves, the flow behaviors of this steel were analyzed and the typical 3D processing map was constructed to clarify the stable processing parameter domains during the continuous deformation process. Then, by the typical 3D processing map and microstructure observation, the 3D deformation mechanism map was constructed to connect the processing parameters and microstructural mechanisms. Subsequently, the 3D activation energy map was constructed to evaluate these deformation mechanisms, and the enhanced deformation mechanism map was constructed. Eventually, based on the enhanced deformation mechanism map, the speed-loading paths for SAE 5137H steel during current-heating compression were designed and they are mapped in a 3D response surface. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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16 pages, 80751 KiB  
Article
Development of Induction Heating System Ensuring Increased Heating Efficiency of the Charge Material in a Forging
by Marek Hawryluk, Marcin Rychlik, Michał Pietrzak, Piotr Górski and Jan Marzec
Materials 2022, 15(4), 1516; https://doi.org/10.3390/ma15041516 - 17 Feb 2022
Cited by 1 | Viewed by 2965
Abstract
This study performs a complex analysis and review of the currently applied methods of inductively heating the charge material in hot die forging processes, as well as elaborates and verifies a more effective heating method. On this basis, a device for inductive heating [...] Read more.
This study performs a complex analysis and review of the currently applied methods of inductively heating the charge material in hot die forging processes, as well as elaborates and verifies a more effective heating method. On this basis, a device for inductive heating using variable frequency inductors was designed and constructed, which made it possible to reduce the scale and decarburization with respect to the heater used so far. In the first place, the temperature distributions in the heater in the function of time were modeled with the use of the CEDRAT FLUX software. The aim of the research was to analyze the temperature gradient and value diversification on the surface and in the material core, as well as to determine the process stability. The following stage was designing and constructing a heater with an automatic system of loading and positioning of the charge on the exit, as well as with a possibility of working in a fully automated system adjusted to the work center. The last stage of investigations was the verification of the elaborated effective heating method on the basis of a short production series and a continuous work for the period of 8 h, both in the quantitative and qualitative aspect (reduced oxidation and decarburization as well as a gradient between the core and the surface). The obtained results confirm the effectiveness of the proposed solution referring to heating the charge material, especially in the aspect of stability and repeatability of the process, as well as a significant reduction in oxidation and decarburization of the material surface. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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16 pages, 10689 KiB  
Article
Wear-Resistance Improvement of 65Mn Low-Alloy Steel through Adjusting Grain Refinement by Cyclic Heat Treatment
by Ying Tong, Yu-Qing Zhang, Jiang Zhao, Guo-Zheng Quan and Wei Xiong
Materials 2021, 14(24), 7636; https://doi.org/10.3390/ma14247636 - 11 Dec 2021
Cited by 10 | Viewed by 3394
Abstract
Refined microstructures achieved by cyclic heat treatment significantly contribute to improving the wear resistance of steels. To acquire the refined microstructures of 65Mn low-alloy steel, first, the specimens were solid solution-treated; then, they were subjected to cyclic heat treatment at cyclic quenching temperatures [...] Read more.
Refined microstructures achieved by cyclic heat treatment significantly contribute to improving the wear resistance of steels. To acquire the refined microstructures of 65Mn low-alloy steel, first, the specimens were solid solution-treated; then, they were subjected to cyclic heat treatment at cyclic quenching temperatures of 790–870 °C and quenching times of 1–4 with a fixed holding time of 5 min. The mechanical properties of 65Mn low-alloy steel in terms of hardness, tensile strength, elongation and wear resistance were characterized. Afterwards, the effect of cyclic heat treatment on microstructure evolution and the relationships between grain refinement and mechanical properties’ improvement were discussed. The results show that the average grain size firstly decreased and then increased with the increase in the quenching temperature. Hardness increased with grain refinement when the temperature was lower than 830 °C. Once the temperature exceeded 830 °C, hardness increased with the temperature increase owing to the enrichment of carbon content in the martensite. With the increase in cyclic quenching times, hardness continuously increased with grain refinement strengthening. In addition, both tensile strength and elongation could be significantly improved through grain refinement. The relationships among wear loss, hardness and average grain size showed that wear resistance was affected by the synthesis reaction of grain refinement and hardness. Higher hardness and refined grain size contributed to improving the wear resistance of 65Mn low-alloy steel. Full article
(This article belongs to the Special Issue Research on Heat Treatment of Advanced Metallic Materials)
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