Optimization of elastoplastic behavior of contact interface for improved contact stress distribution

The elastoplastic behavior of the contact interface, powerfully influencing the contact stress distribution, is investigated to reinforce the uniformity of the contact stress distribution in this paper. Since the contact interface elastoplastic behavior has predominant and direct effects on contact deformation, whereas different contact deformation distributions can result in completely different contact stress distributions, it is theoretically feasible to enhance the uniformity of the contact stress distribution by optimizing the contact interface elastoplastic behavior. To realize this aim, a heuristic-based elastoplastic behavior optimization algorithm is developed, in which the elastoplastic behavior of the contact interface is optimized by changing the yield strength of the materials around contact interface. The uniformity of the contact stress is represented by its variance, and is defined as the objective function. Bilinear material model and von Mises yield criterion are adopted. Two contact cases are presented to evaluate the effectiveness of the proposed elastoplastic behavior optimization algorithm in terms of improving the uniformity of the contact stress. Some new phenomena during the elastoplastic behavior optimization are also observed and explained.