Accuracy of Measurement of Residual Surface Stress by Drilled-Out Method under Varying Condition of Stress Distribution in the Section

Abstract

A stainless clad material very often suffers considerable change of its residual stress distribution near the boundary between the stainless and the mild steel, and the following results was obtained from the analysis of as well as experiments on the accuracy of the surface stress as determined by the completely relaxed method like a drilled-out method, trepanning method, etc. under the above mentioned residual stress condition.
(1) The surface stress of a stainless section almost completely relaxes and shows a true value when the ratio of the thickness of a strainless section to a drilled-out inner diameter is approximately 1/3 or more.
(2) The determined value is less than the true value, when this ratio is less than 1/3, and it suggests that other methods may be applied.