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The Effect of Rra Treatment on Mechanical Properties and Wear Behavior in Vanadium Micro-Alloyed Hadfield's Steel

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SSRN 2023年

作者： Wang, Rui Zhang, Wen Zhang, Fei Fu, Hao Huang, Qinyuan Wu, Hong Li, Zulai Shan, Quan School of Material Science and Engineering Kunming University of Science and Technology Kunming650093 China National & Local Joint Engineering Laboratory for Technology of Advanced Metallic Solidification Forming and Equipment Kunming650093 China Yunnan Kungang Wear Resistant Material Science Co. Ltd. Kunming650093 China State Key Laboratory of Powder Metallurgy Central South University Changsha410083 China

To solve the ongoing problems of micro-alloyed Hadfield’s steel, insufficient hardness and excessive deformation in the early working period, expensive alloying elements like Ti, Nb, and V have been utilized. However, traditional long-time, single-stage aging exacer-bates vanadium to assemble at the edge of initial precipitates, which diminishes estimated effects. For this, here we report the tremendous impact of retrogression and re-aging process(RRA) in this steel by booming the V (C, N) mean sized in 11nm. The procedure enhances the micro-hardness, yielding strength, tensile strength, and impact-wear resistance for more than 27.4%, 29.5%, 22.2%, and 51.5%, respectively. Moreover, the wear mechanism of RRA samples has been investigated in that micro-sized precipitates surrounded by numerous nano V(C, N) stick in the matrix and hinder the abrasive embedding consistently, thus decreasing the micro-cutting and micro-plowing. This new process maximizes the utilization of costly and nonrenewable vanadium and magnifies the impact-wear resistance under either medium or high-intensity working conditions. © 2023, The Authors. All rights reserved.

关键词： Wear resistance

The Influence of Nb on Hierarchical Microstructures in High-Entropy Superalloys

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SSRN 2024年

作者： Ma, Yiqin Ji, Qiuying Ngai, Sieglind Li, Jingzhen Pavel, Michael J. Weaver, Mark L. Zhang, Peng Li, Wei Wu, Yuan Vogel, Florian Jinan University Institute of Advanced Wear & Corrosion Resistant and Functional Materials Guangdong Province Guangzhou510632 China Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic Materials Guangdong Province Guangzhou510640 China School of Mechanical and Automobile Engineering South China University of Technology Guangdong Province Guangzhou510640 China Pico Electron Microscopy Center Innovation Institute for Ocean Materials Characterization Technology Center for Advanced Studies in Precision Instruments Hainan University Hainan Province Haikou570228 China Key Laboratory of Pico Electron Microscopy of Hainan Province Hainan University Hainan Province Haikou570228 China Jinan University Institute of Mass Spectrometry and Atmospheric Environment Guangdong Province Guangzhou510632 China Department of Metallurgical and Materials Engineering The University of Alabama TuscaloosaAL35401-0202 United States University of Science and Technology Beijing State Key Laboratory for Advanced Metals and Materials Beijing Beijing Beijing100083 China

In this investigation, we explore the impact of Nb on the microstructural and mechanical properties of high-entropy Superalloys (HESAs), focusing on hierarchical microstructures. Utilizing a series of HESAs with varying Nb contents, our study employs advanced characterization techniques, including differential scanning calorimetry (DSC) for thermal analysis, electron probe micro-analyzer (EPMA) for compositional analysis for the design of a homogenization treatment at 1,500 K/24 h. Transmission electron microscopy (TEM) reveals that the addition of Nb refines the γ' precipitates and influences the size and volume fraction of embedded hierarchical γ particles. ThermoCalc equilibrium phase analysis and Vegard’s-law calculations reveal a minimal lattice misfit between these phases, highlighting the interplay between Nb content and phase stability. Increasing Nb concentrations inhibit the formation of hierarchical γ particles. We observe an enhancement in hardness from 433 HV to 492 HV with increasing Nb. This study provides valuable insights into the role of Nb in HESAs with hierarchical microstructures, demonstrating its significant influence on γ particle formation within γ’ precipitates and mechanical strength. The findings advance our understanding of alloy design and pave the way for developing advanced HESAs for high-temperature applications. © 2024, The Authors. All rights reserved.

关键词： Entropy

Effect of Ti-Cr Filler on Microstructure, Mechanical Properties, and Thermal Shock Resistance of Tzm/Graphite Brazed Joints

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SSRN 2023年

作者： Liu, Dong-Guang Zou, Jin-Xin Zhang, Peng Zhou, Si-Wei Liu, Hui Li, Ze-Qun Anhui Province Key Lab of Aerospace Structural Parts Forming Technology and Equipment Industry & Equipment Technology Hefei University of Technology Hefei230009 China School of Materials Science and Engineering Hefei University of Technology Hefei230009 China Anhui YaLan Seal Component Co. Ltd Chuzhou233200 China Fujian Provincial Key Laboratory of Advanced Materials Processing and Application Fujian University of Technology Fuzhou350118 China Intelligent Manufacturing Institute Hefei University of Technology Hefei230009 China

One series of TZM/Ti-40Cr/graphite brazed joints were successfully obtained by connecting TZM alloy and graphite with Ti-40Cr filler through brazing in controlled atmosphere. The brazed joints' microstructure, mechanical properties, and thermal shock properties were characterized by X-ray diffraction, scanning electron microscopy, and a 3D laser confocal measuring microscope. The results indicated that the interface microstructure of TZM/graphite brazed joints was graphite/Cr3C2/TiC/Ti-Cr(Mo)/Ti-Mo(Cr)/TZM, and the thickness of the brazing seam increases with increasing temperature. In contrast, the thickness of the carbide reaction layer near the graphite side gradually becomes thicker. The shear tests showed that the joint's strength increased with the temperature increase in a specific temperature range. Maximum shear strength of 26.5 MPa was reached when the joint with groove structure brazed at 1480°C. The effect of holding time on the joints was similar to that of temperature, but the thickness of the carbide reaction layer did not change with holding time. The optimal brazing process for TZM/Ti-40Cr/graphite brazed joints was to hold for 20 min at 1480°C. TZM/Ti-40Cr/graphite brazed joints were subjected to a laser thermal shock test. The results indicated that, at most, TZM/Ti-40Cr/graphite brazed joints could only withstand laser thermal shock of 20A current. When the current rose to 40A, the TZM/Ti-40Cr/graphite joint was penetrated by laser, and the damage depth reached -253.67 μm and -254.824 μm. © 2023, The Authors. All rights reserved.

关键词： Brazing

Optimization of Microstructure and Properties of Brazed Diamond Interface Controlled by Micro-Mn Alloying of Cu Based Filler Metal

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SSRN 2023年

作者： Cui, Bing Liu, Zhengwei Du, Quanbin Jiang, Tao Liu, Juan Sui, Yudong Deng, Hailiang Tong, Baohong School of Materials Science and Engineering Anhui University of Technology Ma'anshan243002 China Henan Key Laboratory of Intelligent Manufacturing Equipment Integration for Super hard Materials Henan Mechanical and Electrical Vocational College Xinzheng451191 China National-Local Joint Engineering Laboratory for Technology of Advanced Metallic Solidification Forming and Equipment Kunming University of Science and Technology Kunming650093 China School of Mechanical Engineering Anhui University of Technology Ma'anshan243002 China

In this experiment, the brazing of diamond with Cu-Sn-Ti-Ga filler metal was investigated in depth, aiming at reducing the thickness of TiC layer, regulating the microstructural distribution at the interface between diamond abrasive grains and filler metal, and exploring the optimum amount of Mn element to be added. The microscopic interface between the cast filler metal and the post-brazing specimen was analyzed in detail using scanning electron microscope and energy spectrometer, and the effect of Mn element on the interfacial structure was investigated in conjunction with the first nature principle. The results show that with the increase of Mn element in the Cu-Sn-Ti-Ga filler metal, the supercooling degree of the filler metal increases, the Sn3Ti5 phase becomes fine, and the content of eutectic organization increases. On the contrary, the thickness of the TiC layer at the brazed diamond interface decreases with the addition of Mn elements, while the bias of Ti and Sn elements at the interface decreases. The smoothest filler metal and the smallest porosity at the diamond-grain-substrate interface can be observed when the addition of Mn reaches 4 wt.%. The results of the first-principles calculations further validate that manganese reduces the titanium-catalyzed diamond graphitizing, which in turn reduces the thickness of the TiC layer as well as the deviation of titanium at the interface. In addition, friction and wear tests show that the samples prepared at a Mn addition of 4 wt.% has the best cutting efficiency and the highest service life. © 2023, The Authors. All rights reserved.

关键词： Microstructure

Effect of Process Parameters on the Formability, Microstructure and Mechanical Properties of Laser-Arc Hybrid Welding of Q355b Steel

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SSRN 2022年

作者： Bi, Jiang Zhang, Liping Peng, Genchen Yuan, Xiaoming Li, Wen Zhang, Lijie Hebei Key Laboratory of Heavy Machinery Fluid Power Transmission and Control Yanshan University Qinhuangdao066004 China Jiangsu XCMG Construction Machinery Research Institution Ltd. Xuzhou221000 China Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education of China Yanshan University Qinhuangdao066004 China

Thick plate steel structure is widely used in construction machinery, pressure vessels, ships and other manufacturing fields. To obtain an acceptable welding quality and efficiency, the thick plate steel is always joined by laser-arc hybrid welding technology. In this paper, the Q355B steel with the thickness of 20 mm was taken as the research object, and the process of narrow groove laser-arc hybrid welding was studied. The results showed that the laser-arc hybrid welding method could realize one backing and two filling welding with the single groove angles of 8-12°. At different plate gaps of 0.5 mm, 1.0 mm and 1.5 mm, and the shape of weld seams were satisfied with no undercut, blowhole or other defects. The average tensile strength of welded joints was 486~493 MPa, and the fracture position was in the base metal area. Due to the high cooling rate, a large amount of lath martensite formed in heat affected zone (HAZ) and this zone exhibited higher hardness values. The impact roughness of the welded joint was almost 66-74 J with different groove angles. © 2022, The Authors. All rights reserved.

关键词： Microstructure

Significant strength improvement in dissimilar TiAl/Ti 2 AlNb joints by pulsed-current diffusion welding with Ti-6Al-4V Interlayer: Multifaceted strengthening mechanisms and high-temperature performance

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Intermetallics 2025年 185卷

作者： Jiafeng Fan Xiaoqiang Li Qi Jiang Penghui Tu Haoxi Zhang Xincheng Rong Wenjie Jian Shengguan Qu Chao Yang Guangdong Key Laboratory for Advanced Metallic Materials Fabrication and Forming National Engineering Research Center of Near-Net-Shape Forming for Metallic Materials South China University of Technology Guangzhou 510640 China

The development of high-strength TiAl/Ti 2 AlNb joints represents a pivotal and challenging research frontier in the fabrication of novel lightweight, high-temperature-resistant turbine components. In this study, we employed Ti-6Al-4V foils as an interlayer for the pulsed-current diffusion bonding (PCDB) of dissimilar TiAl/Ti 2 AlNb joints, a strategy that yielded remarkable results. The tensile strengths of the newly-developed joints at both room temperature and elevated temperatures showed substantial improvements compared to previously reported TiAl/Ti 2 AlNb joints. Specifically, the optimal PCDB joint exhibits a room-temperature strength of 607.8 MPa and a high-temperature strength of 527.9 MPa at 700 °C. The interfacial microstructure of this high-strength joint has unique structural features. The interlayer consists of an island-distributed α p phase and a lamellar α+β structure, while the diffusion bonding layers (DBLs) on both sides are respectively composed of the bilayered α 2 +α phases and the β phase strengthened by acicular α 2 . The strengthening mechanisms of the joints are multifaceted. They encompass solid-solution strengthening and second-phase strengthening of the interfacial microstructure, optimization of the phase composition within the interface. The reduction of thermal stress caused by the addition of the interlayer is also considered a reason for the improvement of high-temperature strength. This research not only furnishes insights into the design and manufacturing of high-performance TiAl/Ti 2 AlNb joints but also serves as a reference for their more extensive applications in cutting-edge aerospace and high-temperature engineering domains.

关键词： Diffusion bonding

The γ′ morphologies regulated by heat treatments change the deformation mechanisms in a novel nickel-based superalloy

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Journal of Alloys and Compounds 2025年 1032卷

作者： Fan, Xingyun Liu, Yanzhuo Ren, Qianlong Li, Xiaowei Du, Hongqiang Wei, Yongsheng Shi, Yingnan Hou, Xinmei Wang, Jinhui Jin, Peipeng Qinghai Provincial Key Laboratory of New Light Alloys Qinghai Provincial Engineering Research Center of High Performance Light Metal Alloys and Forming Salt Lake Chemical Engineering Research Complex Qinghai University Xining810016 China Qinghai provincial Engineering Research Center of Casting and Forging Qinghai Sino Titanium Qingduan Equipment Manufacture Ltd. Co. Haidong810700 China GAONA Aero Material Co. Ltd Beijing100081 China Department of Physical Chemistry University of Science and Technology Beijing Beijing100083 China

Near-isothermal forging is an effective method for manufacturing the parts of the superalloy. In this study, a novel as-extruded nickel-based superalloy (NNS) was subjected to heat treatment at varied temperatures to regulate the alloy microstructure. The results show that the morphologies of the secondary γ′ are flower-like, spherical, and cubic blocks treated at 1100 ℃, 1150 ℃ and 1175 ℃, respectively. A hot compression experiment was conducted to investigate the effect of γ′ on the deformation behaviors and the temperature and strain rate were set to 1150 ℃ and 0.01 s−1. The results show that the alloys after heat treatment at 1150 ℃ and 1175 ℃ do not show significant dynamic softening behavior during thermal compression. Notably, in the alloy heat-treated at 1175 ℃, the γ′ reprecipitated during hot compression, with significant distribution along grain boundaries. This enhanced the pinning effect on the grain boundaries, leading to increased flow stress during deformation (91.5 MPa). The true stress-strain curve indicates that, under the same deformation parameters, the alloy treated at 1175 ℃ exhibits significant dynamic softening during deformation, which is attributed to the formation of dynamic recrystallization (DRX). In addition to discontinuous (DDRX) and continuous dynamic recrystallization (CDRX), the γ′ induced DRX was also observed. It was found that the cubicization behavior of the secondary γ′ morphology after heat treatment at 1175 ℃ strengthens the hindrance to dislocation slip, which changes the hot compression deformation mechanisms of the alloys. © 2025 Elsevier B.V.

关键词： Dynamic recrystallization

Materials Removal Mechanism of Single Crystalline Sic with Laser-Induced Periodic Surface Structures (LIPSS)

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SSRN 2023年

作者： Chen, Pei Chi, Zhuangzhuang Pan, Rui Qin, Fei Qiu, Pei Huang, Jiaxu Xu, Shaolin Institute of Electronics Packaging Technology & Reliability Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Beijing Key Laboratory of Advanced Manufacturing Technology Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Institute of Intelligent Forming Equipment and System Faculty of Materials and Manufacturing Beijing University of Technology Beijing100124 China Department of Mechanical and Energy Engineering Southern University of Science and Technology Shenzhen518055 China

The surface modification by ultra-fast laser could regulate the mechanical properties of hard and brittle materials. Since silicon carbide (SiC) is too hard to be machined with acceptable removal rate and quality by mechanical abrasives, and femtosecond laser (fs-laser) assisted grinding could be a potential method to improve the machinability of SiC. Under fs-laser modulating, SiC surface could be modified to generate laser-induced periodic surface structures (LIPSS). Understanding the mechanical properties and material removal mechanism of the LIPPS surface is crucial to accomplish a high efficiency and quality machining process. This paper aims to investigate the effects of fs-laser modification on the mechanical properties, removal mechanism, removal efficiency, and microstructure changes of 4H-SiC surface during removal, together with those of the original 4H-SiC surface for comparison. The hardness and elastic recovery ability of the modified layer are determined by nano-indentation test, and the nano-scratch test is adopted to study the materials removal behavior. The removal efficiency and the quality of the modified surface is significantly improved. Phase transformation is observed in the scratching area, which reveals the existence of ductile mode removal. Moreover, the stress distribution and the change of scratching force on the surface of SiC before and after modification are studied by finite element method (FEM). The results show that the stress distribution and transmission when scratched on the modified surface is lower than that of the original surface, and the scratching force under the same scratch conditions is greatly reduced. Therefore, the fs-laser modification of SiC could be an effect method to improve the grinding efficiency and quality in mass production of industry. © 2023, The Authors. All rights reserved.

关键词： Silicon carbide

Hybrid forming mechanism of patternless casting and laser cladding

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Frontiers of Mechanical Engineering 2019年第4期14卷 393-401页

作者： Zhongde SHAN Fuzhen SUN Yang LIU China Academy of Machinery Science and Technology Beijing 100044China State Key Laboratory of Advanced Forming Technology&Equipment Beijing 100083China

In accordance with the requirement of manufacturing dies quickly and economically,a hybrid forming method of stamping dies for automobile panels is *** method combines digital patternless casting and high-power laser *** experimental study is conducted on the hybrid forming process and its trial production and application in the manufacturing of stamping dies for typical *** prove that the laser cladding layer exceeds HRC60(Rockwell hardness)and thus meets the production efficiency requirement of automobile *** rate of defects is well *** with traditional technology,this technology has remarkable advantages and advancement.

关键词： patternless casting laser cladding hybrid forming rapid tooling