Grant: Collaborative Research and Development Grants

Cast aluminum cylinder blocks have replaced cast iron blocks to gain a 40% reduction in weight. To attain wear resistance at the bore, 2-mm thick cast iron liners are commonly used inside the cylinder. Recently, thermal spray coating of iron/steel powder has offered a liner-less cylinder by providing a 200-micrometer thick interface between the cylinder bore and the piston, providing a further reduction of weight. However, the characteristics of the coating, its properties, bonding mechanisms, and steel coating/aluminum substrate interface characteristics and properties are not available and/or well understood. These properties are of paramount importance in computer aided design (CAE), and integrated computational materials engineering (ICME). In this project, the mechanical behavior of thermal spray coated cylinders will be studied. This study will identify the microstructural characteristics of the coating, substrate, and interface; and will obtain the mechanical properties of the coating, interface and substrate under quasi-static and cyclic load. Potential failure mechanisms of the coating including delamination and/or cracking will be studied. The study will establish a link between coating microstructure, thermal spray process, and coating properties.