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

采用微柱压缩试验研究了TiAl/Ti 3Al双相层状合金的“本征”界面变形抗力随试样尺寸的变化规律。微柱试样通常在试样中部含有平行于压缩轴的孪晶界面。通过对相同尺寸试样的屈服应力差的尺寸依赖性，推导出了“界面内禀变形抗力”。证明了“界面内禀变形阻力“的大小基本上取决于孪晶界上各变形模式之间的不相容性，且只能用μm以下的试样来确定。

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.