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Effect of alloying elements on microstructure, mechanical and damping properties of Cr-Mn-Fe-V-Cu high-entropy alloys

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Journal of Materials Science & Technology 2018年第11期34卷 2014-2021页

作者： Ruokang Song Fan Ye Chenxi Yang sujun wu School of Materials Science and Engineering Beihang University (BUAA)

A series of new Cr-Mn-Fe-V-Cu high-entropy alloys were prepared by arc melting and suction *** is found that with the addition of Cu, the structure of the alloys evolved from BCC ＋ BCC1 phases to BCC ＋ FCC phases. With increase of Cu, the volume fraction of the Cu-Mn-rich FCC phase increased, and the morphology of the FCC phase transformed from granular particles to long strips and blocks. Compared with other reported HEAs, the Cr-Mn-Fe-V-Cu HEAs exhibit a good balance between strength and ductility. The CrMn0.3 FeVCu0.06 alloy with granular FCC particles exhibits the highest compressive yield strength（1273 MPa） and excellent ductility（εf= 50.7%）. Quantitative calculations for different strengthening mechanisms demonstrate that dislocation and precipitate strengthening are responsible for high strength of the CrMn0.3 FeVCu0.06 alloy, while the solid solution strengthening effect is very low because of its small atomic-size difference. In addition, the CrMn0.3 FeVCu0.06 alloy exhibits good damping capacity due to its high dislocation and interface damping effects. Therefore, the dislocation density and distribution of FCC phase are the crucial factors for improvement of both mechanical properties and damping capacity of the HEAs.

关键词： High-entropy alloy Phase formation Mechanical properties Damping capacity

Anisotropic growth of nano-precipitates governed by preferred orientation and residual stress in an Al-Zn-Mg-Cu alloy

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Journal of Materials Science & Technology 2024年第21期188卷 234-251页

作者： Runze Wang Hongyun Luo sujun wu Tianshu Zhao Xin Wang Robert O.Ritchie School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of Aerospace Materials and Performance Beihang UniversityBeijing 100191China Beijing Key Laboratory of Advanced Nuclear Materials and Physics Beihang UniversityBeijing 100191China Beijing Advanced Innovation Centre for Biomedical Engineering Beihang UniversityBeijing 100191China Surface Engineering Institution AECC Beijing Institute of Aeronautical MaterialsBeijing 100095China Department of Materials Science and Engineering University of CaliforniaBerkeleyCA 94720USA

Through an understanding of diffusion,precise control of the size distribution of nano-precipitates can be essential to developing superior properties in precipitation-strengthened *** a significant influence of crystallographic orientation on the diffusion process is known to exist in low-symmetry hexagonal close-packed alloys,such anisotropic diffusion is still unidentified in high-symmetry cubic *** this work,we reveal the diffusion-controlled coarsening induced anisotropic growth process of nano-precipitates in an Al-Zn-Mg-Cu *** experimental and theoretical studies demonstrate that with an increase in the residual stress,the diffusion-controlled coarsening rate is slow along thefiber texture in the alloy matrix with smaller grain *** such,we find that the diffusion activation energy will be increased along the preferred orientation with largest residual stress,which leads to a reduced diffusion-controlled coarsening ***,we demonstrate that the increase in the volume fraction of nano-precipitates originates from the rapid grain-boundary controlled coarsening of the grainboundary *** on these results,an underlying microstructural design strategy is proposed,involving the crystallographic orientation,the residual stress and the grain boundaries to manipulate the precipitate size distribution in this class of alloys.

关键词： Aluminum alloy Precipitate coarsening behavior Preferred orientation Diffusion coefficient Residual stress

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晋南牛ApoA1基因克隆及组织表达谱分析

中国草食动物科学 2025年第1期45卷 1-10页

作者：李希宋菲菲王曦王宏浩吴苏君张元庆张变英山西农业大学动物科学学院山西农业大学生态农牧研究所

为研究晋南牛载脂蛋白A1(ApoA1)基因的结构、生物学功能及其在不同组织中的表达变化规律，本试验以晋南牛肝脏组织总RNA为模板，克隆ApoA1基因序列，并利用多种生物信息学在线分析软件对晋南牛的ApoA1基因进行生物信息学分析及构建系统... 详细信息

为研究晋南牛载脂蛋白A1(ApoA1)基因的结构、生物学功能及其在不同组织中的表达变化规律，本试验以晋南牛肝脏组织总RNA为模板，克隆ApoA1基因序列，并利用多种生物信息学在线分析软件对晋南牛的ApoA1基因进行生物信息学分析及构建系统发育进化树。利用荧光定量PCR方法检测晋南牛心脏、肝脏、脾脏、肺脏和肾脏等组织中ApoA1基因的表达情况。结果表明，晋南牛ApoA1基因的CDS序列全长852 bp，与黄牛ApoA1基因的同源性为98.00%。晋南牛ApoA1蛋白的分子量为30 276.35 Da，由265个氨基酸残基构成，属于亲水性蛋白，有20处磷酸化位点。在ApoA1的二级结构中，α-螺旋占92.08%，属于全α类蛋白。ApoA1蛋白与ApoA2、ApoB、ApoE、ApoC2、ApoC3、SCARB1、LPL、ABCA1等蛋白存在相互作用。基于ApoA1序列同源性构建的系统发育进化树表明，晋南牛与黄牛的亲缘关系最近，与野牛的亲缘关系最远。ApoA1基因在晋南牛肝脏、心脏、脾脏、肺脏和肾脏组织中均有表达，且以肝脏中的相对表达量最高，肾脏中的相对表达量最低。

关键词：晋南牛 ApoA1 克隆组织表达

镉胁迫下野生大豆苗期性状全基因组关联分析及耐镉候选基因筛选

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河南农业科学 2025年第1期54卷 40-54页

作者：车雅丽吴苏峻王坤杨王艳丽张锴乔亚科袁泉河北科技师范学院农学与生物科技学院/河北省作物逆境生物学重点实验室河北秦皇岛066000 河北科技师范学院分析测试中心河北秦皇岛066000 集发农业梦想王国河北秦皇岛066000

野生大豆是栽培大豆的近源种,具有丰富的耐逆等位基因。为筛选耐镉野生大豆种质资源并解析其耐镉分子机制,以冀东地区205份野生大豆品系作为研究材料,采用水培试验,设置镉胁迫和对照(不进行镉胁迫)2个处理以及2022年11月和2023年7月2个... 详细信息

野生大豆是栽培大豆的近源种,具有丰富的耐逆等位基因。为筛选耐镉野生大豆种质资源并解析其耐镉分子机制,以冀东地区205份野生大豆品系作为研究材料,采用水培试验,设置镉胁迫和对照(不进行镉胁迫)2个处理以及2022年11月和2023年7月2个环境重复,测定苗期地上部鲜质量(SFW)、地下部鲜质量(RFW)、株高(PH)、根长(RL),计算鲜质量根冠比(RSR)、各性状对应的耐镉系数(CTC)及各个野生大豆材料的耐镉综合评价值(D值),同时进行全基因组关联分析(GWAS),并对15号染色体上的显著单核苷酸多态性(SNP)进行单倍型分析。结果表明,除RSR外,镉胁迫处理幼苗性状平均值均低于对照;频率分析结果显示,2个环境下的CTC均表现为正态分布,呈现数量性状遗传特性;参照D值筛选出13份耐镉野生大豆种质。主成分分析显示,205份野生大豆材料可被分为3个类群;连锁不平衡(LD)分析发现,205份野生大豆自然群体在100 kb处出现衰减。GWAS分析共检测到195个与野生大豆耐镉性状显著相关的SNP,单个SNP可解释1.95%~25.43%的表型变异。根据SNP的物理位置共鉴定到591个候选基因,其中11个候选基因分别由多个SNP重复关联到,属于一因多效。更重要的是,根据功能注释发现了2个金属耐性蛋白(MTPs)基因和2个重金属相关蛋白(HIPPs)基因,分别是LOC114386540(MTP 10-like)、LOC114388453(MTP 10-like)、LOC114369981(HIPP 36-like)和LOC114381753(HIPP 37-like),这4个基因为阐明野生大豆耐镉性状遗传的分子机制奠定了基础。单倍型分析发现,15号染色体上的单倍型2的平均耐镉系数最大,属于优异单倍型。

关键词：野生大豆镉胁迫全基因组关联分析(GWAS) 耐镉系数候选基因

Influence of different rolling processes on microstructure and strength of the Al–Cu–Li alloy AA2195

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Progress in Natural Science:Materials International 2022年第1期32卷 87-95页

作者： Fan Ye Ling Mao Jian Rong Baoshuai Zhang Lijun Wei Sihan Wen Haojun Jiao sujun wu International Research Center for Advanced Structural and Biomaterials School of Materials Science and Engineering Beihang University School of Materials Science and Engineering Beihang University Aerospace Research Institute of Materials & Processing Technology

The influence of different rolling processes on precipitation behaviour, crystallography texture, grain morphology,and their consequent effects on tensile properties for Al–Cu–Li alloy AA2195 was investigated in the present *** H-T8 samples(hot rolled + T8) presented better tensile strength and ductility(with serious strength anisotropy) than the HC-T8 samples(hot rolled + cold rolled + T8), due to their different microstructures and textures. The higher dislocation density was found in the H-T8 samples, which promoted the nucleation of main strengthening phase T1in the matrix and suppressed the grain boundary precipitation, resulted in better strength and ductility. The increase of the dynamic recovery(DRV) during hot rolling enhanced the generation of Brass texture, and brought serious strength anisotropy. The cold rolling was performed after the hot-rolling process for the HC-T8 samples which increased deformation energy and resulted in full recrystallization of the deformed microstructure during the following solution treatment. The formation of recrystallized microstructure reduced the dislocation density and the heterogeneous precipitate nucleation positions which limited the strengthening phase precipitation in matrix and accelerated the precipitation along grain boundaries, resulted in fewer T1precipitates, coarse grain-boundary precipitates(GBPs), and wider precipitate-free zones(PFZs). The localized strain may be concentrated on the grain boundary to induce the dislocation pile-up, breaking of the GBPs, and intergranular fracture during stretching.

关键词： Al-Cu-Li alloys Rolling Mechanical properties Microstructure evolution Fracture

Fatigue Crack Growth Behavior of Different Zones in an Annealed Automatic Gas Tungsten Arc Weld Joint of TA16 and TC4 Titanium Alloys

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Journal of wuhan University of Technology(Materials Science) 2020年第6期35卷 1090-1097页

作者： SHAO Ling wu sujun PENG Wenya DATYE Amit JU Hongbo LIU Ying Research Institute of Zhejiang University-Taizhou Zhejiang UniversityTaizhou 318000China School of Materials Science and Engineering Beihang UniversityBeijing 100191China AECC Hunan Aviation Powerplant Research Institute Zhuzhou 412000China Department of Mechanical Engineering&Materials Science Yale UniversityNew HavenCT 06511USA Key Laboratory of Advanced Welding Technology of Jiangsu Province Jiangsu University of Science and TechnologyZhenjiang 212003China Institute of Technology of Aircraft Engine Beijing Research Institute of Aviation EngineeringBeijing 100024China

Based on the investigated microstructure of different zones in the annealed automatic gas tungsten arc weld joint of TA16 and TC4 titanium alloys,the mechanical property of them was assessed under fatigue crack growth rate *** evaluation of fatigue crack growth rate,three points bending specimens were *** correlation between the range of stress intensity factor and crack growth rate was determined in different zones of the annealed weld *** crack growth rates were obviously different in different zones of weld joint of dissimilar titanium alloys,due to their different *** electron microscope examinations were conducted on the fracture surface in order to determine the relevant fracture mechanisms and crack growth mechanisms with respect to the details of microstructure.

关键词： dissimilar titanium alloys joining weld joint microstructure fatigue crack growth rate fracture

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调磁环材料性能对永磁齿轮损耗的影响研究

机械工程学报 2022年第22期58卷 269-275页

作者：鲁仰辉罗帅吴素君北京航空航天大学材料科学与工程学院北京100191 国家电投集团科学技术研究院有限公司北京102209

磁场调制型永磁齿轮作为一种新型永磁变速装置,易产生较大磁场损耗,降低永磁齿轮工作效率,限制其传递能力的进一步提升。提出整体成型动力传动式调磁环提高了扭矩传动能力,建立调磁环三维模型开展了强度、刚度和损耗计算,并结合永磁齿... 详细信息

磁场调制型永磁齿轮作为一种新型永磁变速装置,易产生较大磁场损耗,降低永磁齿轮工作效率,限制其传递能力的进一步提升。提出整体成型动力传动式调磁环提高了扭矩传动能力,建立调磁环三维模型开展了强度、刚度和损耗计算,并结合永磁齿轮性能测试分析了调磁环骨架材料和调磁极片材料的损耗,研究三种不同调磁环承载骨架材料参数对永磁齿轮损耗和效率的影响,对永磁齿轮参数进行优化并确定最优扭矩骨架承载材料。结果表明,特种工程塑料调磁环骨架材料能大幅降低永磁齿轮损耗,有效提升传动效率,永磁齿轮实测传动效率可达93.8%。

关键词：磁齿轮永磁变速损耗调磁环材料特种工程塑料

K417G服役涡轮导向叶片的组织性能及热疲劳损伤机理分析

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稀有金属材料与工程 2019年第5期48卷 1517-1522页

作者：宋若康马东吴素君北京航空航天大学

对服役后低压涡轮导向叶片的组织性能及热疲劳行为进行了系统研究,结果表明,K417G合金在服役后组织发生明显的弱化,γ’相的网状组织长大、粗化严重高温拉伸与室温拉伸试验结果的对比表明,K417G合金在高温下力学性能出现大幅降低,这主... 详细信息

对服役后低压涡轮导向叶片的组织性能及热疲劳行为进行了系统研究,结果表明,K417G合金在服役后组织发生明显的弱化,γ’相的网状组织长大、粗化严重高温拉伸与室温拉伸试验结果的对比表明,K417G合金在高温下力学性能出现大幅降低,这主要是由于合金内析出相之间的相界面和晶界在高温下成为合金的薄弱环节,易成为裂纹的起源位置,从而降低了强度,断裂方式也从室温下的韧性断裂逐渐转变为沿晶特征的脆性断裂;叶片在热疲劳应力作用下表面的涂层发生开裂、脱落,基体合金被氧化,氧化物在应力作用下开裂、脱落而形成疲劳裂纹源;热疲劳试验数据的拟合结果表明随着温度循环周次的增加,裂纹扩展速率呈减小的趋势,这是由于随循环周次的增加,二次裂纹出现并生长,释放了热应力,从而降低了裂纹扩展速率。

关键词： K417G合金导向叶片组织弱化热疲劳

一对一责任制助产护理模式对初产妇分娩方式和产程的影响研究

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中国全科医学 2019年第A01期22卷 213-216页

作者：吴素君浙江省兰溪市妇幼保健计划生育服务中心妇产科

目的探究和分析一对一责任制助产护理模式对初产妇分娩方式和产程的影响。方法选择兰溪市妇幼保健计划生育服务中心妇产科2017-01-01至2018-08-30收治的初产妇200例为研究对象。采用随机数字表法将其分为对照组和研究组,各100例。对照... 详细信息

目的探究和分析一对一责任制助产护理模式对初产妇分娩方式和产程的影响。方法选择兰溪市妇幼保健计划生育服务中心妇产科2017-01-01至2018-08-30收治的初产妇200例为研究对象。采用随机数字表法将其分为对照组和研究组,各100例。对照组采用常规助产护理模式干预,研究组采用一对一责任制助产护理模式干预。对比两组分娩方式(顺产、剖宫产),第一、二、三产程时间,产后2 h出血量,新生儿Apgar评分,母婴不良事件发生率。结果研究组顺产率(85.0%)高于对照组(61.0%)(P0.05)。研究组产后2 h出血量﹝(86.8±20.6)ml﹞少于对照组﹝(124.5±27.9)ml﹞,新生儿Apgar评分﹝(9.2±0.7)分﹞高于对照组﹝(7.3±0.8)分﹞(P<0.05)。研究组母婴不良事件发生率(2.0%)低于对照组(19.0%)(P<0.05)。结论对初产妇采用一对一责任制助产护理模式干预,不仅能提高产妇顺产率、缩短其总产程时间,还能减少其产后出血量、降低母婴不良事件发生率,对提高初产妇分娩质量和保障母婴安全具有重要意义。

关键词：围生期医护一对一责任制助产护理模式分娩产程初产妇