摘要
利用光学显微镜、X射线衍射和透射电镜研究了Ti6Al4V合金置氢后的微观组织变化,分析了氢化物的形成机制,通过硬度测试分析了置氢对Ti6Al4V合金硬度的影响。研究结果表明:置氢可以显著降低(α+β)/β转变温度,置氢后的组织中存在斜方结构的马氏体α"和面心立方结构的氢化物δ,氢化物δ不仅可以从α相内析出,还可以从β相析出。文章认为,δ在α相内的形成过程是基于氢元素扩散的相变过程,而β相内的δ是共析反应βH→α+δ的产物。硬度测试的结果显示:随着氢含量的增加,Ti6Al4V合金的硬度增加,这是氢化物析出强化、氢固溶强化、氢与位错的相互作用以及马氏体转变综合作用的结果。
Microstructure variation of Ti6Al4V alloy after hydrogenation was investigated by optical microscopy （OM）, X-ray diffraction （XRD） and transmission electron microscopy （TEM）, and the formation mechanism of hydride was discussed. The influence of hydrogen content on hardness of Ti6Al4V alloy was studied by hardness testing. The result shows that hydrogen could reduce （α＋β）/β transformation temperature obviously. Hydride δ （fcc structure） as well as orthorhombic martensite α″ precipitated in the specimens after hydrogenation, and hydrides precipitated not only from α phase but also from β phase. It is considered in this paper that the formation of δ in a phase is α phase transformation based on the diffusion of hydrogen, and the formation of δ in β phase is the result of eutectoid reaction βH→α＋δ The result of hardness testing shows that the hardness of Ti6Al4V alloy increases after hydrogenation, which is caused by formation of hydrides, hydrogen solution strengthening, interaction between hydrogen and dislocation and martensitic transformation jointly with increasing of hydrogen.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2008年第10期1795-1799,共5页
Rare Metal Materials and Engineering
基金
国家安全重大基础研究项目
