A scanning acoustic Microscopy for estimating the depth of deformed layer

In this paper we propose an experimental method to estimate the depth of deformed layer due to machining using a high frequency ultrasonic technique. A tool steel was used as the workpiece material, and the workpieces were machined using a profile grinder. A point-focus lens on a scanning acoustic microscope was used to measure V(z) curves for calculating SAW propagation velocity from the polished specimens. Microhardness measurements were followed. The estimated depths of deformed layer by the ultrasonic technique are compared with those by the microhardness method. The results show that the ultrasonic technique the feasibility for measuring the depth of deformed layer nondestructively.