Simulation of Partial Autofrettage Residual Stresses by Thermal Loads

摘要

The effect of favorable residual stresses of an autofrettaged tube is well known. In many instances there is a redistribution of these stresses due to changes of geometrical configurations such as the presence of keyways, riflings, cracks, etc. The problem in general, can be studied by discretization carried out either by finite elements or by finite differences; however, it is usually not possible to incorporate the redistributed residual stress patterns due to the presence of such geometric changes. This difficulty is overcome by simulation of residual stresses by certain active loadings. The simulation by dislocation and equivalent thermal loading for a fully autofrettaged tube is well known. In this report we extend the thermal loading to simulate a partially autofrettaged case. The simplicity of the method is illustrated by comparing numerical results to those obtained from finite elements (NASTRAN) and finite differences.