CVD-W的晶界结构及其对塑性形变的影响  

Grain boundary microstructure of CVD-W and its effect on plastic deformation

作　　者：孙红婵[1] 李树奎[1] 侯岳翔[1] 鲁旭东[1] 郭伟[1] 

机构地区：[1]北京理工大学材料科学与工程学院．北京100081

出　　处：《兵器材料科学与工程》2008年第6期76-78,共3页Ordnance Material Science and Engineering

摘　　要：为研究化学气相沉积纯钨(CVD-W)的沉积组织生长对晶界结构的影响,以及晶界结构对塑性形变的影响;采用电子背散射技术观察CVD-W的微观组织,分析晶界结构;采用Hopkinson压杆系统进行高应变率压缩试验。结果表明:CVD-W具有显著的<001>晶粒择优取向,晶界呈现Σ3、Σ5等低重合位置点阵的晶界结构特征,其中Σ3具有最高的出现频率;其高应变下的屈服应力明显低于其他制备方法获得的纯钨材料。研究认为由于CVD-W在界面上具有较多的重合位置,晶界处晶格吻合较好,畸变程度低,界面能较低,而且由于低ΣCSL晶界特点,晶界多是由位错构成的;另外晶粒的择优取向使晶粒间在较低的应力下协调形变,因此CVD-W在较低的应力下即可发生塑性形变。The EBSD technology is used to determine the grain orientation microstructure of CVD-W, as well as Hopkinson bar to carry out high strain rate compression tests, in order to investigate the effects of deposition microstructure on the grain boundary and the grain boundary, on the plastic deformation. The experimental results show that CVD-W obvious preferred orientation on 〈001〉 is confirmed by the anti-extremal graph. Besides,the CSL grain boundaries such as ∑3, ∑5 and so on are occurred. Among these kinds of boundary, the ∑3 boundary has the highest frequency; the yield stress of CVD-W is lower than pure tungsten by other preparation methods. It is found that the structures of grain boundary of CVD-W atoms have low level of distortion and low grain boundary energy. The grain boundaries are constructed of dislocation. In addition, the grains of prefen＇ed orientation 〈001 〉 make plastic deformation coordination occurred in lower stress. CVD-W can carry out plastic deformation in lower stress.

关 键 词：化学气相沉积纯钨 晶界结构 重合位置点阵 晶粒择优取向 

分 类 号：TG146[一般工业技术—材料科学与工程]