Intrinsic Deformation Resistance of Interface. New Interface Structure Properties Deduced by Micropillar Deformation

采用两相TiAl/Ti3Al片层合金，通过微柱压缩试验研究了界面抗变形本征阻力随试件尺寸的变化规律。微柱试件通常在试件中部含有一条平行于压力轴的孪晶边界。通过具有和不具有孪晶边界的相同尺寸试件的屈服应力差的尺寸依赖关系，推导出了“界面本征变形抗力”。结果表明，“界面本征变形抗力”的大小基本上是由孪晶界上各工作变形模式之间的不相容决定的，而且只与尺寸小于μm的试件有关。

With the use of a two-phase TiAl/Ti3Al lamellar alloy, the'intrinsic' interface resistance against the passage of deformation, which is termed"intrinsic deformation resistance of interface"has been investigated by conducting micropillar compression tests as a function of specimen size. The micropillar specimen usually contains a twin boundary parallel to the compression axis in the middle of specimen. The deduction of"intrinsic deformation resistance of interface"was made through the size dependence of the yield stress difference between specimens of the same size with and without a twin boundary. The magnitude of"intrinsic deformation resistance of interface"is proved to be basically determined by the incompatibility among the operative deformation modes across the twin boundary and to be determined only with the specimen whose size is belowμm.