Advances in Hole-Drilling Residual Stress Measurements

Residual stress measurements by hole drilling have developed greatly in both sophistication and scope since the pioneering work of Mathar in the 1930s. Advances have been made in measurement technology to give measured data superior in both quality and quantity, and in analytical capability to give detailed residual stress results from those data. On the technology side, the use of multiple strain gauges, Moiré, Electronic Speckle Pattern Interferometry (ESPI) and Digital Image Correlation all provide prolific sources of high quality data. Modern analytical techniques using inverse methods provide effective ways of extracting reliable residual stress results from the mass of available data. This paper describes recent advances in both the measurement and analytical areas, and indicates some promising directions for future developments