SEMI-NONDESTRUCTIVE RESIDUAL STRESS MEASUREMENT

摘要

Residual stress measurements are made using a strain gauge and stress relief achieved by local melting of a region of the object being tested by a laser beam or other finely directed heat source. Surface strain is measured dynamically before the heat of the molten region diffuses under the gauge and results in thermal stress. The method is semi-nondestructive because the molten region recasts with little loss of material is rapid, and can be utilized on difficult geometries such as the interior surface of reactor pipe.