Problems with Non-Destructive Surface X-Ray Diffractin Residual Stress Measurement

Author:  Paul S. Prevey, Lambda Research
Source:  The Shot Peener magazine, Vol 05 Issue 4 Winter 1992
Doc ID:  1992044
Year of Publication:  1992
Abstract:  
Because surface measuements are nondestructive, x-ray diffraction is often considered as a method of residual stess measurement for quality control testing. Unfortunately, errors caused by the presence of a subsurface stress gradient and difficulties in interpreting surface results often limit the usefulness of surface data. The magnitude of the potential errors, both in measurement and in interpretation, depends upon the nature of the subsurface residual stress distribution which can only be determined destructively. Although residual stress distributions subject to these problems are commonly encountered in practive, the question of the validity of nondestructive surface results is seldom adequately considered.