具有分形结构界面的固体膜/粘滞层/基底层状结构的变形

考虑固体膜/粘滞层/基底结构中粘滞层/基底界面不平整对结构的稳定性,特别是固体薄膜稳定时的褶皱变形产生的影响.考虑自仿射和峰状的粗糙界面.自仿射的粗糙界面由振幅和分形维表征,振幅和分形维越大对结构平衡的影响越大;峰状界面由振幅和平均峰间距表征,振幅越大对结构平衡影响越大,平均峰间距越小对结构平衡影响越大.进而,用有限元方法模拟分析该结构,得到界面平整和不平整两种情况下固体膜面内失稳力.结果表明,粘滞层/基底不平整情况下结构的平衡状态与假设该界面为理想平整面所得的结果有很大不同,在结构尺寸较小的情况下不可假设该界面为理想平整来考察该结构的稳定性.

DEFORMATION OF THIN SOLID FILM/VISCOUS LAYER/SUBSTRATE STRUCTURES WITH ROUGHNESS INTERFACE BETWEEN THE VISCOUS LAYER AND SUBSTRATE

Influence of a roughness interface between liquid layer and substrate on the deformation of the thin solid film/liquid/substrate laminate structure with residual compressive stress was studied by means of the energy method.The roughness of the interface is characterized by two ways such as a self-affine fractal and mound geometry.It is found that the stable deformation appearance of the structure is wrinkling and sinusoidal,which is similar with that for the structure with planar interface,but the wave number of the sinusoidal structure with planar interface can be changed remarkably with the roughness of the interface both for the interface with self-affine fractal geometry and mound geometry.For the interface with self-affine fractal geometry,the effect of the roughness is stronger when the amplitude of the roughness and the fractal dimension are larger.For mound the roughness interface,with increasing of the amplitude and decreasing of the average mound separation,the effects of roughness get more distinguished.It is concluded that the result when the interface is supposed to be planar is very different from that when the interface is nonplanar.