李芳镖,高宁,李奕鹏,洪钢,赵尚泉,冉广

• 1:厦门大学能源学院
• 2:中国科学院近代物理研究所

摘要(Abstract)：

使用分子动力学方法计算模拟了Σ3{112}晶界上含有不同大小和浓度He泡的钨晶体的拉伸性能。应用共近邻分析法和位错分析法分析了晶体屈服前的微观结构演化机理。结果表明:当晶界上无He泡或只含有小尺寸单He泡时,在拉伸屈服前都经历了弹性阶段和结构相变阶段;在结构相变阶段,晶格原子的相对位置发生了变化。拉伸过程中,小He泡造成的晶格损伤会自动恢复,对晶体屈服应力和屈服应变无显著影响,He泡的能量受周围晶格钨原子间距的影响。晶界上的大尺寸He泡造成晶格损伤无法恢复,并且He泡越大,晶格损伤越大,相应地屈服应变、屈服应力和弹性模量越小。晶界上高浓度的He泡易导致晶界脆化,使钨晶体在屈服后就开始断裂分离。

关键词(KeyWords)： 分子动力学;Σ3{112}晶界;金属钨;He泡;拉伸性能

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(11675230,11375242,U1832112);; 厦门大学能源学院发展基金(2018NYFZ01)

作者(Author): 李芳镖,高宁,李奕鹏,洪钢,赵尚泉,冉广

DOI: 10.13289/j.issn.1009-6264.2019-0099

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