钢球和刚性平面弹塑性正碰撞恢复系数研究

采用有限元法(FEM)研究了理想弹性和分段线性/幂指数强化材料钢球与刚性平面的弹性和弹塑性正碰撞。弹性碰撞FEM计算结果和Hertz理论计算结果吻合。弹性碰撞FEM计算结果说明波动效应在球体与刚性平面正碰撞中引起的能量损失可以忽略。弹塑性碰撞的FEM计算结果分别与Johnson和Thornton的理论模型计算结果进行了对比。弹塑性碰撞中,当碰撞速度大于临界速度时发生有限塑性变形,FEM计算结果表明恢复系数与(v/vy)/(E*/σs)]-0.27成正比。

RESEARCH ON ELASTOPLASTIC NORMAL IMPACT OF STEEL SPHERES AGAINST A RIGID PLANE

The normal impacts of perfectly elastic and piecewise linear/power law hardening steel spheres against a rigid plane were studied using finite element methods (FEM). The results of FEM model agreed with those by Hertz theory for elastic impacts. The FEM results of the elastic collisions showed that the kinetic energy dissipated by stress wave propagation could be neglected. The results of elastoplastic impacts were compared with the results of Johnson’s and Thornton’s. When the impact velocity was larger than the critical velocity, the finite plastic deformation started and the coefficient of restitution could be proportional to (v/vy )/( E*/σs)]-0.27 in the elastoplastic impacts.