Accession Number : ADP001609

Title :   The Effects of Compressive Overloads on the Threshold Stress Intensity for Short Cracks,

Corporate Author : WATERLOO UNIV (ONTARIO)

Personal Author(s) : Au,P. ; Topper,T. H. ; El Haddad,M. L.

Report Date : APR 1983

Pagination or Media Count : 7

Abstract : In the present investigation, crack propagation specimens of an aluminum alloy are subjected to continuous and periodic cycles having compressive stresses. Results indicate that for a tension compression load cycle crack growth in the near threshold regime is controlled by the tensile peak stress intensity and the compressive peak stress. Compressive loading significantly reduces the threshold intensity and increases crack growth rate. Furthermore, periodic application of compressive overloads during zero to maximum stress intensity tests is shown to drastically reduce the threshold stress intensity for thousands of cycles following each overload application.

Descriptors :   *Airframes, *Cracking(Fracturing), *Structural mechanics, Aluminum alloys, Compressive properties, Loads(Forces), Fatigue(Mechanics), Crack propagation, Growth(General), Sizes(Dimensions), Overload

Distribution Statement : APPROVED FOR PUBLIC RELEASE