Relationship between texture and macroscopic transformation strain in severely cold-rolled Ti-Nb-Al superelastic alloy
Relationship between texture and macroscopic transformation strain in severely cold-rolled Ti-Nb-Al superelastic alloy
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DOI：
10.2320/matertrans.45.1083
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发表时间：
2004-04-01
影响因子：
1.2
通讯作者：
Miyazaki, S
中科院分区：
文献类型：
--
作者：
Inamura, T;Fukui, Y;Miyazaki, S
采用bcc母相（β）的x射线极图检测了ti - 24mol % nb - 3mol %Al超弹性合金的织构，并根据晶格对应关系和外加应力势能变化评价了转变应变与加载方向的关系。经99%冷轧和1273 K固溶处理后的材料的x射线极形测量证实了发育良好的（β）{112}（β）型再结晶织构。晶体学分析表明，马氏体从β向α”转变的最大膨胀分量是平行于轧制方向的β。从能量上考虑，当再结晶织构出现时，沿RD方向的拉伸应力只会诱发一种α′变异体（晶格对应变异体）。纵向拉伸产生的转变应变是横向拉伸产生的转变应变的3倍左右。计算结果与实验结果吻合较好。
Textures of severely cold-rolled Ti-24 mol%Nb-3 mol%Al superelastic alloy were examined by X-ray pole figure measurements for the bcc parent phase (beta) and the relationship between transformation strain and loading direction was evaluated on the basis of the lattice correspondence and change in the potential energy of an external stress. A well-developed recrystallization texture of (beta){112}(beta) type was confirmed by X-ray pole figure measurements for the material which was 99% cold-rolled followed by a solution-treatment at 1273 K. Crystallographic analysis showed that the maximum dilatation component of the martensitic transformation from beta to alpha" is (beta) parallel to the rolling direction (RD). An energy consideration revealed that only one alpha"-variant (lattice-correspondence variant) can be induced by the tensile stress along RD when the recrystallization texture appears. The transformation strain generated under the RD tension was about three times larger than that generated under the tension along transverse direction (TD). These calculations were in good agreement with experimental evidences.