ELASTIC-PLASTIC STRESS-ANALYSIS OF COLD EXPANDED FASTENER HOLES

A closed form solution technique first presented by Hsu and Forman for the radial expansion of a fastener hole is extended to include elastic-plastic unloading and therefore the creation of a reverse yielded zone. In addition, the dependence of interface pressure upon interference with an elastic insert is established. Numerous parametric studies are presented to demonstrate the effect of significant model variables and selected example calculations are compared with experimental results.