Response Behavior of Local Surface Failure due to Repetitive Impact of Stainless Steel

Abstract

Material property that can describe its behavior under repetitive impact is an important data for the design and failure analysis of any engineering part. Study of this behavior by measuring the size of apparent damaged area at the surface (crater depth) and tracking the damage intensity is extremely difficult for small area. An attempt to develop the understanding of different response behavior during repetitive impact of stainless steel was made in this work. This paper presented the relation of the response signal to the contact surface condition in the repetitive impact test by mean of spectrum analysis. Acceleration response of a specimen under impact load could be affected by contact condition since contact area and local thickness of the specimen could be changed. The testing machine was developed to provide the repetitive impact force to the specimen. Surface morphology and depth of the crater were captured by optical microscope and 2D-stylus profilometer. The appearance in the peak spectrum amplitude of a response signal was found to be a noticeable response behavior that can differentiate the damaged specimen from the healthy specimen. Results of the response spectrum gave a clear relation to the damage intensity of the specimen. The increase in the peak amplitude during the number of impact cycles was found in the damaged specimen while the non-damaged specimen conditions the peak amplitude of the response is constant throughout the test.