Effect of Squeeze Pressure and Strontium Addition on Tribological and Mechanical Properties of Al–Si Piston Alloy with Varying Amount of Ni

Engine pistons manufactured from Al–Si are a particular set of industrial alloys which requires excellent characteristics at higher temperatures (nearly 400 °C). Concurrently, such alloys persist in retaining the properties to abrupt variation in temperature. As a result, the mechanical, tribological and thermal strains needs to be seriously examined unless ignoring the aggressive surroundings, in which they are revealed through exploitation. For performing such a group of requirements, Al alloys allocated for piston manufacturing requires an appropriate microstructure. The alloy microstructure depends on the type and percentage of composition, the casting parameters and schedule of the heat treatment cycle. Typical choices for few alloying elements are in the range 11–23Si; 0.5–3 Ni; 0.5–5.5Cu and 0.6–1.3 Mg.The author presents the benefits of squeeze casting on the microstructure and its characteristics of aluminum–silicon piston alloys. Piston alloys with variable Ni content was investigated experimentally. The role of the heat treatment on the microstructure and properties of the alloys was studied. The role of Sr on Al-Si piston alloy was also examined. The present study aims to develop a novel alloy for piston applications that operates at a higher temperature and high peak firing pressure of the engine. It can be accomplished by adding an alloying element such as Ni to Al-12Si-3Cu-1 Mg-xNi (x varies between 0.5 and 2.5Ni) alloy. Based on mechanical properties and microstructural characteristics, the ideal alloy composition is selected for further research. Later, the role squeeze pressure on the microstructural features, tribological properties and mechanical characteristics on the piston alloys are studied and correlated.