Surface-roughness Study Using Laser Speckle Method

Abstract

Current techniques for surface-roughness measurements can be classified into two broad categories: those using a measuring stylus which requires direct contact with the test object and those using non-contacting laser techniques. In this paper, a whole-field speckle method is employed to determine metallic-surface-roughness. The technique enables evaluation of the roughness of particular points on a surface. Six sets of surfaces prepared by a sparkerosion process with roughness ranging from 0·4-12·5 μm have been tested. Different correlation methods were used to process the test data and a practi-cal method of evaluating surface-roughness is proposed. © 1998 Published by Elsevier Science Ltd. All rights reserved.