Ti-35Nb合金中原子占位对β→ω相变的影响  

Effect of Nb atoms occupancy on β→ω phase transformation in Ti-35Nb alloys

作　　者：孙锦辉 陈冷[1] 孟利 王玉会 

机构地区：[1]北京科技大学材料科学与工程学院,北京100083 [2]钢铁研究总院华东分院北京研发中心,北京100081 [3]北京航空材料研究院,北京100095

出　　处：《中国有色金属学报》2018年第2期267-274,共8页The Chinese Journal of Nonferrous Metals

摘　　要：利用第一性原理计算了Ti-35Nb(质量分数,%)合金的广义层错能,并讨论了合金中Nb原子占位对β→ω相变的影响。结果表明:在β相中沿{112}<111>滑移系开动会引起β→ω相变,形成ω相和孪晶相间隔的"三明治"结构,包含最近邻Nb原子链的{112}<111>滑移系的临界剪切应力约是2126.46 MPa,应力诱发的ω相最小尺寸约是长2.6444 nm,厚1.1297 nm;而包含次近邻Nb原子链的{112}<111>滑移系的临界剪切应力约是180.21 MPa,ω相最小尺寸约是长1.304 nm,厚0.3766 nm,较容易开动。The generalized stacking fault energy was calculated by the first-principles and the influence of Nb atoms occupancy on the induced β→ω phase transformations was discussed in Ti-35 Nb（mass fraction, %） alloy in this work. The results show that the opening of {112}111systems in β phase can form ω phase alternated along twinning so called ＂sandwich＂ structure. Meanwhile the critical shear stress of {112}111 slip systems including the nearest neighbor Nb atoms chains is 2126.46 MPa in perfect crystal, and form the minimum ω phases with 2.6444 nm in length and 1.1297 nm in width. Furthermore, the critical shear stress of {112}111 slip systems including the next nearest neighbor Nb atoms chains is 180.21 MPa in perfect crystal, further, the minimum ω phase has 1.304 nm in length and 0.3766 nm in width.

关 键 词：Ti-35Nb合金 β→ω相变 原子占位 广义层错能 

分 类 号：TG146.23[一般工业技术—材料科学与工程]