HR2合金微结构演化及塑性变形机理研究  

Microstructural evolution and plastic deformation mechanism of HR2 alloy

作　　者：尚福林[1] 陈雁[1] 张永梅[1] 杨增钦 余勇[2] 闫亚宾[2] 晏顺平[2] 李侃[3] 

机构地区：[1]西安交通大学航天航空学院,西安710049 [2]中国工程物理研究院总体工程研究所,四川绵阳621900 [3]中国航天科技集团公司第四研究院第四十一所,西安710025

出　　处：《中国科技论文》2016年第22期2589-2596,共8页China Sciencepaper

基　　金：高等学校博士学科点专项科研基金资助项目(20110201110019);国家自然科学NSAF联合基金资助项目(U1330116)

摘　　要：为建立准确可靠的塑性本构关系,研究了HR2抗氢钢在塑性变形过程中微结构演化以及变形机理;采用薄片状微小尺寸试样开展了单向拉伸准静态加载测试,分别将试样拉伸至不同应变量时进行卸载;利用金相分析、XRD和EBSD等微结构分析手段分析不同变形量情况下合金的微结构信息。结果表明:随着变形量增大,HR2钢原始的等轴晶被拉长,晶粒被细化;当变形量超过10%时,形变马氏体的含量逐渐增大;合金中位错明显增殖,位错密度增大;孪晶和织构在原始组织和拉伸试样中均少量存在;根据力学测试和微结构分析结果,HR2合金在常温准静态下主要表现为位错滑移变形机制,林位错机制明显;随着变形量的增加,形变马氏体产生并对塑性变形的影响逐渐增强,而孪晶和织构的影响可以忽略。This paper aims to investigate the microstructural evolution and plastic deformation mechanism of HR2 hydrogen resistant steel,and to develop a more accurate constitutive relation of plasticity.Uniaxial tensile tests using miniaturized specimens are conducted for HR2 alloy under quasi static loading conditions.The tensile tests are unloaded after reaching different amount of strains,and micro-structural analyses are done to follow the micro-structural evolution of the samples.The results show that the equiaxed grains in HR2 hydrogen resistant steel are elongated and refined with the increasing of deformation,and the dislocation multiplication occurs in the alloy as well.When the deformation exceeds 10%,the content of deformation martensite increases gradually.It is demonstrated that dislocation glide is the active deformation mechanism at quasi-static loading conditions.At the initial stage of plastic deformation,the solid solution atoms form Cottrell atmosphere which pins dislocation,which lead to dislocation forest mechanism.The martensitic phase transformation becomes apparent at the mediate deformation stages.In addition,the influence of twins and texture on dislocation motion can be ignored due to the limited content.

关 键 词：HR2合金 抗氢钢 微结构演化 塑性变形 变形机制 

分 类 号：TG142.1[一般工业技术—材料科学与工程]