RETRACTED: Coating thickness and roughness effect on stress distribution of A356.0 under thermo-mechanical loadings (Retracted Article)

Cast aluminium-silicon alloy, A356.0, is widely used in automotive components such as diesel engine cylinder heads and also in aerospace industries because of its outstanding mechanical, physical, and casting properties. Thermal barrier coatings are applied to combustion chamber in order to reduce fuel consumption and pollutions and also improve fatigue life of components. However, studies on behaviour of A356.0 with thermal barrier coating are still rare. The purpose of the present work is to simulate stress distribution of A356.0 under thermo-mechanical cyclic loadings, using a two-layer elastic-visco-plastic model of ABAQUS software. The results of stress-strain hysteresis loop are validated by an out of phase thermo-mechanical fatigue test. Then, ceramic coating thickness effect on stress distribution of test specimens is investigated. Different thicknesses from 300 to 800 microns of top coat and also roughness of the interfaces are simulated to get best stress gradient which can cause an improvement of fatigue life. Studying realistic interface roughness shows the critical area of tensile stress which results in crack initiation. Furthermore increasing TC thickness results in stress growth. (C) 2011 Published by Elsevier Ltd. Selection and peer-review under responsibility of ICM11