全片层TiAl合金临界屈服应力及影响因素的细观研究  

Researches of Yield Stress and Influential Parameters for PST Crystals of TiAl Based on Micromechanics

作　　者：苏继龙[1] 胡更开[1] 

机构地区：[1]北京理工大学应用力学系,北京100081

出　　处：《材料科学与工程学报》2003年第4期535-538,共4页Journal of Materials Science and Engineering

摘　　要：基于PST晶体的微结构和γ相及α2 相普通位错和孪晶滑移启动 ,结合细观力学方法 ,通过数值模拟两相中的各滑移系上的分切应力 ,得出PST晶体屈服应力和外加载荷与片层之间夹角θ的关系 ;详细讨论了γ相中孪晶与普通位错的临界切应力之差异对PST晶体屈服应力的影响。对单轴和双轴加载的情况分别进行了计算 ,得到的结论与已有的一些实验结果相吻合。Micromechanics theory is used to analyze the yield stress of polysynthetically twinning(PST) crystals of TiAl. as a function of the loading angle θ . The numerical results of yield strength, based on considering the lamellar microstructure and the deformation mechanisms such as ordinary slip and true twinning in PST composed of γ and α 2 phase, is obtained by using calculating of resolved shear stresses in all slip systems. The difference of CRSS in ordinary slip and true twinning in PST was considered in this paper. Uniaxial loading and biaxial loading are simulated respectively and the calculated data show good agreement with the experimental results.

关 键 词：TIAL合金 临界屈服应力 影响因素 Γ相 Α2相 PST晶体 普通位错 

分 类 号：TG146.23[一般工业技术—材料科学与工程]