Advanced Contact Mechanics

Abstract

In this chapter a range of more difficult concepts arising in the analysis of contacts will be discussed. This chapter may therefore be omitted at first reading and studied after crack analysis techniques have been mastered. Three specific topics are covered, viz. the influence of elastic material mismatch, contacts subjected to torsion, and the presence of layers in the contacting bodies, including the influence of finite thickness. All of these extensions to the basic theory may be made in closed form, and represent the development of concepts introduced in chapters 2 and 3. There exists, however, a wide range of practically occurring contacts where neither the half-plane nor strip approximations is justified, for example where a contact occurs very close to the edge of a block of material. Under these conditions a completely numerical scheme may be unavoidable. Even where the half-space assumption may be retained, many problems arise which are neither axi-symmetric nor plane — these may profitably be analyzed using a numerical scheme, but based on a half-space influence function formulation, which provides a computationally more efficient strategy than the finite element technique. These numerical approaches to the analysis of contacts are also discussed in the present chapter.