【摘要】 近等原子比热轧态 Ni Ti合金板材有较显著的择优取向 ,使该合金的相变伪弹性呈现明显的各向异性 .拉伸实验表明 :拉伸轴沿与轧向成 45°夹角的方向 ,相变伪弹性最好 ;沿轧向 ,次之 ;沿横向 ,最差 .文中对 Ni Ti织构进行了取向分布函数定量分析 ,并改进了 Ni Ti单晶相变应变的晶格变形矩阵理论 ,以取向分布密度为加权因子 ,对该合金多晶的相变伪弹性进行了计算机模拟 ,所得结果与实测值吻合得较好 .更多还原

【Abstract】 A modified model based on Phenomenological theory of martensitic transformation was used to predict the transformation strain anisotropy of NiTi single crystals. The texture of polycrystalline NiTi were determined using ODF (Orientation Distribution Function). The crystallographic textures and tensile pseudo elasticity at different angles to the rolling direction were correlated by averaging the transformation strain of constituent grains (single crystals) weighted with the respective orientation distribution densities. The calculated and experimental strains are well compatible despite the discrepancy due to the hypothesis of unconstrained grain deformation in polycrystalline alloys.更多还原