Repeatability of Incremental Hole Drilling and Slitting Method Residual Stress Measurements

Abstract

Residual stresses are of interest from an engineering perspective because they can have a significant influence on material performance. For example, fatigue initiation, fatigue crack growth rate, stress corrosion cracking, and fracture are all influenced by the presence of residual stress. The commonly used methods for residual stress measurement include incremental hole drilling and slitting. This paper establishes the repeatability of these techniques through replicate measurements on nominally similar specimens. Each technique was used to measure the residual stress in peened aluminum plates at multiple locations. A statistical analysis of the data was performed to compare the level of repeatability obtained using the two techniques. The standard deviation of the slitting method data was about 2 % of the peak stress magnitude, compared with 5 % for the hole drilling measurements.