摘要
目的通过真空电弧熔炼、冷轧及热处理工艺,系统研究了热处理制度对(FeCoNi)_(86)Al_(7)Ti_(7)(原子数分数)高熵合金微观组织与力学性能的影响。方法采用X射线衍射(XRD)、扫描电子显微镜(SEM)和能谱分析(EDS)等表征手段,系统分析了合金的物相组成、显微结构及元素分布。结果再结晶态合金由FCC单相固溶体组成,具有典型的等轴晶粒特征,元素分布均匀,无明显的化学成分偏析。经过时效热处理后,合金的相结构与显微组织发生显著变化。在780℃时效4 h条件下,合金中形成了不规则片层状L2_(1)相;随时效温度的升高,不规则片层状L2_(1)相逐渐消失,仅在晶界观察到微量微米级L2_(1)相,同时基体中形成高密度、共格分布的球形L1_(2)纳米析出相。力学性能测试结果表明,780℃时效4 h样品具备最优综合性能,其屈服强度、抗拉强度与延伸率分别达到1067.2 MPa、1504.4 MPa和14.3%。结论本研究不仅为调控高熵合金的热处理性能提供了重要理论支撑,还为深入探究(FeCoNi)_(86)Al_(7)Ti_(7)高熵合金的微观组织与力学性能的内在关联提供了科学指导。
The work aims to systematically investigate the effects of heat treatment on the microstructure and mechanical properties of(FeCoNi)_(86)Al_(7)Ti_(7)(at.%)high-entropy alloys prepared by vacuum arc melting,cold rolling and heat treatment processes.Characterization techniques including X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy dispersive spectroscopy(EDS)were employed to systematically analyze the phase composition,microstructure and elemental distribution of this alloy.The recrystallized alloy consisted of a single-phase face-centered-cubic(FCC)solid solution with typical equiaxed grains and uniform elemental distribution,showing no significant chemical segregation.After aging treatment,notable changes in phase constitution and microstructure were observed.At 780℃for 4 h,irregular lamellar L2_(1) phases formed in the alloy.As the aging temperature increased,these irregular lamellar L2_(1) phases gradually disappeared,with only a small amount of micron-sized L2_(1) phases at grain boundaries,while a high density of coherent spherical L1_(2) nanoprecipitates formed in the matrix.Mechanical tests revealed that the sample aged at 780℃for 4 h exhibited the best combination of properties,with yield strength,tensile strength and elongation reaching 1067.2 MPa,1504.4 MPa and 14.3%.This work not only provides crucial theoretical support for regulating the properties of high-entropy alloys through heat treatment,but also offers scientific guidance for further exploring the intrinsic relationship between microstructure and mechanical properties in the(FeCoNi)_(86)Al_(7)Ti_(7) high-entropy alloy.
作者
杨圣豪
孙钦虎
陈志博
叶汇
赵友贤
马盼
贾延东
YANG Shenghao;SUN Qinhu;CHEN Zhibo;YE Hui;ZHAO Youxian;MA Pan;JIA Yandong(School of Materials Science and Engineering,Shanghai University of Engineering Science,Shanghai 201620,China;School of Materials Science and Engineering,Shanghai University,Shanghai 200444,China)
出处
《精密成形工程》
北大核心
2025年第12期54-61,共8页
Journal of Netshape Forming Engineering
基金
上海市大学生创新训练项目(cs2505009)
上海市探索者计划(25TS1401900)
上海市科技创新行动计划(24CL2901500)
上海市关键技术研发计划(25CL2902300)。
关键词
高熵合金
热处理
微观组织
力学性能
high-entropy alloy
heat treatment
microstructure
mechanical properties
