Cavitation erosion characteristics of hard chromium plated diesel engine cylinder liner

Abstract

ABSTRACT Hard chromium plating was performed to prevent the cavitation erosion of a diesel engine cylinder liner and the damage characteristics of the plating layer were analysed by conducting a cavitation erosion test with an amplitude of 50 µm according to the ASTM G-32 standard in a coolant. The surface damage was analysed using a scanning electron microscope and a 3D optical microscope before and after the test, and the weight loss of the specimen was determined. The surface analysis result showed the occurrence and growth of local damage of micro-tunnel shape on the surface of the plating layer, and both the surface damage depth and weight loss tended to increase. This local damage was observed to occur and grow first in the spherical grain microstructure of the plating layer. Consequently, it is thought that cavitation erosion attack will cause local damage of the hard chromium plated cylinder liner.