娄照坤,刘继文,林雅婷,王君阳,张璐

• 1:沈阳航空航天大学材料科学与工程学院
• 2:沈阳航空航天大学航空制造工艺数字化国防重点学科实验室

摘要(Abstract)：

采用真空电弧熔炼炉制备了Co_(36)Ni_((37-x))Cr_(20)Al_3Ti_2Nb_x(x=2、3和4,原子分数，%)中熵合金，利用扫描电镜(SEM)、能谱仪(EDS)、透射电镜(TEM)及拉伸试验机等研究了合金的微观组织、力学性能、强化机制及变形机制。结果表明：随着Nb含量的增加，合金晶粒的平均尺寸增大，且晶界处析出相的成分和形状也发生改变。当Nb含量为2%和3%时，析出相为富Al、Nb的片状析出相，当Nb含量提升至4%时，出现了富Ti、Nb的块状析出相。随Nb含量的增加，合金的强度提高，伸长率下降。Nb含量由2%提升到4%,合金的屈服强度由940 MPa提升至1177 MPa,极限抗拉强度由1246 MPa提升至1271 MPa,伸长率由13.67%下降至3.75%。合金强度提升的原因是Nb元素的加入增强了固溶强化和沉淀强化。合金形变初期主要依靠层错诱导形变实现，合金变形后期主要依靠位错运动实现。

关键词(KeyWords)： 中熵合金;力学性能;强化机制;变形机制

Abstract:

Keywords:

基金项目(Foundation): 沈阳航空航天大学航空制造工艺数字化国防重点学科实验室开放基金资助项目(SHSYS202205);沈阳航空航天大学创新创业训练计划项目(D202302271902448979)

作者(Author): 娄照坤,刘继文,林雅婷,王君阳,张璐

DOI: 10.13289/j.issn.1009-6264.2023-0483

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