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研究了无限大基体内纳米尺度圆孔表面薄膜中界面螺型位错形核的临界条件,薄膜考虑了表/界面效应。运用弹性复势方法,获得了两个区域应力场的解析解答,并导出位错形核能公式,由此讨论了表/界面效应对薄膜界面位错形核的影响规律。算例结果表明,表/界面效应在纳米尺度下对位错形核的影响显著,不同表/界面效应下位错形核的临界薄膜厚度有很大差异,当基体与薄膜的相对剪切模量超过某一值后,只有考虑负的表/界面应力时位错才有可能形核;薄膜厚度在小于某一临界尺寸时负的表/界面应力更容易位错形核,薄膜厚度大于某一临界尺寸时正的表/界面应力更容易位错形核。
The critical conditions of interfacial screw dislocation nucleation in nanoscale circular-hole surface films in infinite matrix were studied. The film considered the surface / interface effect. The analytical solution of the stress field in two regions is obtained by using the elastic re-potential method, and the dislocation nucleation energy formula is deduced. The influence of the surface / interface effect on the dislocation nucleation at the film interface is discussed. The experimental results show that the effect of surface / interface on dislocation nucleation is significant at nanoscale. The critical film thickness of dislocation nucleation varies greatly with different surface / interface effects. When the relative shear modulus Beyond a certain value, dislocations are only likely to nucleate when negative surface / interface stresses are taken into account. Negative surface / interface stresses are more susceptible to dislocation nucleation when the film thickness is less than a certain critical dimension, and film thicknesses greater than one Positive tab / interfacial stress is more susceptible to dislocation nucleation at critical dimensions.