Thermo mechanical analysis of a partially ceramic coated piston used in an SI engine

The purpose of this paper is to determine the temperature and the stress distributions in a partial ceramic coated spark ignition (SI) engine piston. Effects of coating thickness and width on temperature and stress distributions were investigated including comparisons with results from an uncoated piston. It is observed that the coating surface temperature increase with increasing the thickness in a decreasing rate. Surface temperature of the piston with 0.4 mm coating thickness was increased up to 82 degrees C. The normal stress on the coated surface decreases with coating thickness, up to approximately 1 mm for which the value of stress is the minimum. However, it rises when coating thickness exceeds 1 mm. As for bond coat surface, increasing coating thickness, the normal stress decreases steadily and the maximum shear stress rises in a decreasing rate. The optimum coating thickness was found to be near 1 mm under the given conditions. (C) 2010 Elsevier B.V. All rights reserved.