伪弹性TiNi合金圆薄板的准静态力学行为实验研究

采用阴影云纹和应变片方法对伪弹性TiNi合金圆板在固支条件下的准静态力学行为进行了实验研究,得到了载荷位移曲线、全场离面位移和局部应变等数据.载荷位移曲线呈现非线性、滞回耗能和无残余变形的特性,表明试样已经发生马氏体相变.应变测量显示,相变局限于加载中心较小区域,相变区内,环向应变大于径向应变,且拉伸侧应变大于压缩侧的应变.有限元模拟揭示出相变区内两侧表层的相变范围、相变铰区和马氏体相含量的不对称分布规律.

Experimental Research on Quasi-static Mechanical Behaviors of Thin Circular Plate of Pseudo-elastic TiNi Alloy

Experimental research on quasi-static mechanical behaviors of fixedly stayed thin circular plate consisted of pseudo-elastic TiNi alloy was conducted through the approach of shadow Moiré and foil gauge. Load-displacement curve, full-field out-of-plane displacement and local strain were obtained. The load-displacement curve demonstrates non-linear character, hysteretic energy and non-residual deformation, which indicates Martensitic transformation of sample. According to the strain measurement, the transformation is limited to a small part of the loaded center, within the transformation region, circumferential deformation is greater than radial deformation, and the deformation of dragging end is greater than that of compressing end. It is revealed through finite-element simulation that the nature of the transformation range, transformation hinge area, and the asymmetric distribution principle of Martensitic phase contents on the surface of both sides of transformation area.