Analysis of piston microstructure in the most critical zones

Abstract

This paper presents the results of testing the microstructure in the most critical zones of pistons made of aluminum piston alloys. The paper analyzes the shape, size and distribution of primary Si crystals and other phases in three most important piston zones (the edge of the combustion chamber, the area of rings groove and piston pin boss). The phase stoichiometry was identified by comparing the results of EDS analysis with the results reported in the studied literature. The results show that the necessary size, shape and distribution may be obtained in specific zones if appropriate solidification conditions are provided that are necessary for the formation of specific phases.