复合材料层合板静压痕接触的等效弹性模量

在复合材料层合板静压痕接触问题中,由于层合板接触区域的纤维走向发生了变化,导致沿厚度方向的弹性模量产生变化并随着凹坑深度的增加而增大。本文建立压头压入后的力学分析模型,得到了与凹坑深度相关的沿厚度方向的等效弹性模量;将等效弹性模量代入目前被广泛接受的修正Hertz接触理论,建立了新的接触力与凹坑深度的关系式。通过与静压痕试验中接触力和凹坑深度的关系进行比较,结果表明该接触关系式能较好地描述接触力和凹坑深度的关系。与文献修正理论相比,在压痕较小时,本文的修正结果较好。

A modified method of static indentation contact theory for composite laminates

In the static indentation contact problems of composite laminates,with the variation of the fiber direction of the contact area,the elastic modulus along the thickness direction changes and increases with the increment of dent depth.Based on the mechanics analysis model,we get the equivalent elastic modulus along the thickness direction which associate with the dent depth.Then the equivalent elastic modulus is put into the modified Hertz contact theory which was widely accepted.So we establish a new formula for the contact force and the dent depth,and made a modification to the original contact theory.By Comparison with the results of the static indentation test,it is found that the new formula of the contact theory described the relationship between the contact force and the dent depth better.