Effect of microrelief on the contact shakedown of fixed joints

Resumo

Under the conditions of cyclic loading at fixed joints, the repeated mutual slip of the contacting surfaces is observed in the contact zone, fretting appears, and the wear and destruction of the assembly elements occurs. The existing methods for overcoming fretting are aimed at reducing its intensity. The finite element analysis of fixed joints of smooth contact surfaces and surfaces with relief under the conditions of cyclic loading of junctions makes it possible to reveal the regions of mutual slip and, to determine the parameters of the microrelief, which contribute the most to the onset of contact shakedown. The method for improving the resistance to fretting in friction units based on achieving the conditions for the onset of contact shakedown using microrelief is implemented for fixed joints of a hard-alloy cutter pick and a drilling bit rolling cutter, as well as for an abutting joint of the rotor impeller shrouds of a universal gas distributor.