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Modification and aging precipitation behavior of hypereutectic AI-21wt.%Si alloy treated by P+Ce combination

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China Foundry 2014年第6期11卷 516-521页

作者： Liu Pei Wang Aiqin xie jingpei Materials Science and Engineering School of Henan University of Science and Technology

In the present study, the tested hypereutectic Al-21wt.%Si alloys were prepared by modifying the melt using different proportions of P and Ce, and then applying T6 heat treatment. The modification effects and mechanism of P＋Ce complex modifier on the Si phase of hypereutectic Al-21wt.%Si alloy were studied, and the aging precipitation behavior after modification was characterized by means of tensile strength measurement, OM, SEM and TEM analysis. The results show that the massive primary silicon phase particles are significantly refined after modification, while the needle-like eutectic silicon crystals become fibrous and short. It was found that the mechanism of phosphorus modification on the primary silicon can be attributed to heterogeneous nucleation of AlP, while the modification mechanism of Ce can be explained by adsorbing-twinning theory. In the aged microstructure of the modified hypereutectic Al-21wt.%Si alloy, there existed some strengthening phases such as AI4Cu9, Al2Cu, AlCu3, and Al57Mn12. The P＋Ce complex modifier not only affected the size of primary silicon and eutectic silicon, but also the aging behavior of alloys under the heat treatment process. When Al-21wt.%Si alloy was modified using 0.08%wt.P ＋ 0.6wt.% Ce, the aging precipitates were dispersed uniformly in the alloy, and its mechanical properties at room and elevated temperatures are optimized （Rm = 287.6 MPa at RT, Rm = 210 MPa at 300 ℃）.

关键词： combination modification hypereutectic Al-21wt.%Si alloy microstructure aging precipitation

Superior strength-plasticity synergy in a heterogeneous lamellar Ti_(2)AlC/TiAl composite with unique interfacial microstructure

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Journal of Materials Science & Technology 2023年第28期159卷 21-32页

作者： Pei Liu Bo Hou Aiqin Wang jingpei xie Zhenbo Wang Feng Ye College of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471023China Provincial and Ministerial Co-construction of Collaborative Innovation Center for Non-ferrous Metal New Materials and Advanced Processing Technology Luoyang 471023China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

Improving the plasticity of TiAl alloys at room temperature has been a longstanding challenge for the de-velopment of next-generation aerospace *** adopting the nacre-like architecture design strategy,we have obtained a novel heterogeneous lamellar Ti_(2)AlC/TiAl composite with superior strength-plasticity synergy,i.e.,compressive strength of∼2065 MPa and fracture strain of∼27%.A combination of micropil-lar compression and large-scale atomistic simulation has revealed that the superior strength-plasticity synergy is attributed to the collaboration of Ti_(2)AlC reinforcement,lamellar architecture and heteroge-neous *** specifically,multiple deformation modes in Ti_(2)AlC,i.e.,basal-plane dislocations,atomic-scale ripples and kink bands,could be activated during the compression,thus promoting the plas-tic deformation capability of ***,the lamellar architecture could not only induce sig-nificant stress redistribution and crack deflection between Ti_(2)AlC and TiAl,but also generate high-density SFs and DTs interactions in TiAl,leading to an improved strength and strain hardening *** addi-tion,profuse unique Ti_(2)AlC(1¯10¯3)/TiAl(111)interfaces in the composite could dramatically contribute to the strength and plasticity due to the interface-mediated dislocation nucleation and obstruction *** findings offer a promising paradigm for tailoring microstructure of TiAl matrix composites with extraordinary strength and plasticity at ambient temperature.

关键词： Ti_(2)AlC/TiAl composite Heterogeneous lamellar microstructure Micropillar compression Interface-mediated deformation Strength-plasticity synergy

Effect of Heat Treatment on Microstructure and Mechanical Properties of Si Cp/2024 Aluminum Matrix Composite

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Journal of Wuhan University of Technology(Materials Science) 2015年第6期30卷 1229-1233页

作者：柳培王爱琴 xie jingpei HAO Shiming School of Materials Science and Engineering Henan University of Science and Technology School of Physical and Engineering Henan University of Science and Technology

SiCp/2024 aluminum alloy matrix composite was prepared by powder metallurgy method. Effects of heat treatment on the microstructure and mechanical properties of composite were investigated by SEM, EDS, XRD, HREM, tensile and hardness tests. The experimental results showed that SiC particles distributed uniformly in the matrix and were in good combination with matrix. The tensile strength and hardness were improved significantly after heat treatment. With the increase of solid solution temperature, the alloy phases dissolved in the matrix gradually. When the solid solution temperature arrived at 505 ℃, the alloy phases dissolved thoroughly, and the composite exhibited the highest tensile strength and hardness（σb=360 MPa, HBS=104）. The main strengthening phase was Al2Cu, which was granular and distributed dispersively in the matrix. Effect of T6 was better than that of T4 at the same solid solution temperature.

关键词： SiCp/2024 aluminum matrix heat treatment microstructure mechanical properties

Influence of Different Al Contents on Microstructure, Tensile and Wear Properties of Zn-based Alloy

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Journal of Materials Science & Technology 2010年第7期26卷 648-652页

作者： Shuqing Yan jingpei xie Zhongxia Liu Wenyan Wang Aiqin Wan Jiwen Li Department of Physics and Laboratory of Materials Physics of the Ministry of Education of China Zhengzhou University Zhengzhou 450052 China College of Materials Science and Engineering Henan University of Science and Technology Luoyang 471003 China

The influence of different Al contents on the microstructure, hardness, tensile and wear behavior of Zn-based alloys was investigated in the present study. The test results show that alloy with 27% Al content shows the higher ultimate strength and elongation percent at room and elevated temperatures. It also exhibits the higher wear resistance at all loads in view of the higher tightness of Zn-27Al alloy. Increasing Al content from 33% to 48% results in improvement of ultimate strength and elongation percent at room and elevated temperatures. However, the ultimate strength and elongation percent of the ZA48 alloy are still lower than that of Zn-27Al alloys. The reason can be attributed to the increasing segregation and voids with increasing Al contents.

关键词： Zinc-based alloys Mechanical property Wear property

Contact Resistance and Arc Erosion of Tungsten-copper Contacts in Direct Currents

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 816-822页

作者：马窦琴 xie jingpei LI Jiwen WANG Aiqin WANG Wenyan School of Materials Science and Engineering Henan University of Science and Technology Luoyang 471023 China Non-ferrous Metal Generic Technology Collaborative Innovation Center of Henan Province Luoyang 471023 China

The arc erosion under medium direct currents in the argon flow was tested on tungsten-copper（W-Cu） contacts which were processed by hot extrusion and heat treatment. The scanning electron microscopy（SEM） and transmission electron microscopy（TEM） were used to study the microstructure of the W-Cu powders and compacts. The contact resistance, arcing energy, and arcing time were continuously measured by JF04C contact materials test system. Changes in tungsten-copper contact surface were observed by SEM. The test results showed that the arcing time and arcing energy all increase with current and voltage, but the changes of average contact resistance are more complicated. For a short arcing time, the average contact resistance decreases with increasing current due to the vaporization of Cu. However, for a longer arcing time, it slightly increases due to the formation of high resistant films, compound copper tungsten. The formation of compound copper tungsten was confirmed by the increased Rc kept in the range from 1.1 to 1.6 mΩ. The compound copper tungsten is first exposed with a tungsten and copper-rich surface, and then totally exposed due to evaporation of copper from the surface. At last a stabilized surface is created and the crystals decrease from 8 μm to 2 μm caused by the arc erosion.

关键词： Tungsten-copper contacts arc erosion contact resistance surface analysis

TiC纳米颗粒强化9Cr耐热钢的微观组织及力学性能

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金属热处理 2025年第1期50卷 187-195页

作者：朱晓龙王争辉王文焱谢敬佩刁晓刚张飞扬河南科技大学材料科学与工程学院河南洛阳471023 洛阳洛北重工机械有限公司河南洛阳471100 中信重工洛阳重铸铁业有限责任公司河南洛阳471632

为提高汽轮机用耐热钢的高温强度,制备了添加不同含量TiC纳米颗粒(质量分数分别为0%、0.01%、0.05%、0.1%)的9Cr耐热钢,利用高温激光扫描共聚焦显微镜(LSCM)、光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)等分析了含0.01%TiC纳米颗粒... 详细信息

为提高汽轮机用耐热钢的高温强度,制备了添加不同含量TiC纳米颗粒(质量分数分别为0%、0.01%、0.05%、0.1%)的9Cr耐热钢,利用高温激光扫描共聚焦显微镜(LSCM)、光学显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)等分析了含0.01%TiC纳米颗粒耐热钢的显微组织,并通过拉伸和冲击试验分析了力学性能。结果表明,TiC纳米颗粒的加入能明显增强9Cr耐热钢的600℃高温强度,且当添加量为0.01%时,抗拉强度最大为356 MPa,断裂时应变为38%;含0.01%TiC纳米颗粒的9Cr耐热钢在空冷条件下得到马氏体组织,第二相碳化物类别为M_(6)C,TiC纳米颗粒分布在晶内起到弥散强化作用;添加量为0.01%的耐热钢经1040℃退火+990℃正火+740℃回火后的综合力学性能优良,硬度、抗拉强度、屈服强度、伸长率和断面收缩率分别为177 HBS、734 MPa、538 MPa、15.45%和31.15%,拉伸断口观察有大量韧窝,为韧性断裂;室温冲击吸收能量为116 J,韧脆转变温度FATT_(50)为-15℃。

关键词：纳米颗粒增强 9Cr耐热钢汽轮机微观组织力学性能

Numerical simulation of stress field in inclusions of large rudder arm steel castings

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China Foundry 2009年第3期6卷 219-225页

作者： Yang Dixin xie jingpei Zhang Kefeng Liu Zongfa Wang Aiqin Wang Wenyan School of Material Science and Engineering Henan University of Science and TechnologyLuoyang 471003HenanChina School of Material Science and EngineeringHenan University of Science and TechnologyLuoyang 471003HenanChina School of Material Science and EngineeringHenan University of Science and TechnologyLuoyang 471003HenanChina School of Material Science and EngineeringHenan University of Science and TechnologyLuoyang 471003HenanChina School of Material Science and EngineeringHenan University of Science and TechnologyLuoyang 471003HenanChina School of Material Science and EngineeringHenan University of Science and TechnologyLuoyang 471003HenanChina

The influence of non-metallic inclusions on quality and performance of steel depends on not only the quantity of inclusions,but also the type,shape,size,distribution,and deformation behavior. In this paper,ANSYS finite element analysis software is used to simulate the stress field of inclusions appearing in heavy rudder arm steel castings,the effects of inclusion type,shape,distribution,and various loading conditions were studied. The micromechanics of inclusions in such castings were also analyzed. Such research provides further clarification on reaction mechanism of inclusions under complex loading conditions.

关键词： ANSYS inclusions stress concentration maximum stress

Influence of titanium content on wear resistance of electrolytic low-titanium eutectic Al-Si piston alloys

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China Foundry 2008年第3期5卷 162-166页

作者： Wang Jiefang xie jingpei Yan Shuqing Liu Zhongxia Weng Yonggang Wang Mingxing Song Tianfu The Key Laboratory of Material Physics Ministry of Education Zhengzhou University Zhengzhou 450052 Henan China Henan University of Science and Technology Luoyang Henan China

The wear resistance of six kinds of the electrolytic low-titanium eutectic AI-Si piston alloys with various Ti content ranging from 0.00wt.% to 0.21wt.% has been studied. A new method of adding Ti is adopted in the electrolytic low-titanium aluminum alloy ingots. The electrolytic low-titanium eutectic AI-Si piston alloys are produced by remelting the electrolytic low-titanium aluminum alloy, crystal silicon, pure magnesium, AI-50%Cu and AI-10%Mn master alloy. The wear experiments are conducted using MM200 wear testing machine under lubricating condition. The results indicate that the better wear resistance and the less weight loss are achieved in the study for the eutectic AI-Si piston alloys with 0.08wt.%-0.12wt.% Ti content. The highest ultimate tensile strength of 135.94 MPa at 300℃ and HV141.70 hardness of the alloys are obtained at 0.12wt.% and 0.08wt.% Ti content, respectively. The wear mechanism of the eutectic AI-Si piston alloys under lubricating condition is abrasive wear.

关键词： electrolytic low-titanium aluminum alloy eutectic Al-Si piston alloy wear resistance

Damping Property of Supersaturated ZnA127Ce Alloy during Natural Aging

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Journal of Materials Science & Technology 2001年第1期17卷 9-10页

作者： jingpei xie Yaomin ZHU Yanpei SONG Xiaoying WANG and Quande CHEN Dept.of Material Engineering , Luoyang Institute of Technology, Luoyang 471039. China Dept.of Material Engineering Luoyang Institute of Technology

The microstructures and damping property of supersaturated ZnA127Ce alloy during natural aging have been investigated. H-800 TEM was mainly used to research the microstructures. The relationship between microstructure and damping property was primarily studied. The results showed that solution plus natural aging was the best heat treatment, which could improve the damping property. Both continuous precipitation and cellular reaction occurred during the aging. Continuous precipitation follows the sequence: β→spherical GP zones→elliptical GP zones→intermediate phase R→n. The cellular reaction can be written as follows:β→a+n+ε.

关键词： Ce Damping Property of Supersaturated ZnA127Ce Alloy during Natural Aging