PENGARUH VARIASI KOMPOSISI PENGECORAN PISTON BEKAS TERHADAP KARAKTERISTIK MATERIAL PISTON

Abstract

Recycling the pistons to achieve quality equals the additional material needed.The addition of silicon carbide is given with the hope of increasing challenging on the piston. The purpose of this study is to compare the results of the former piston casting by comparing silicon carbide with the original piston. Used piston casting with metal molds and the addition of silicon carbide are given with various variations, namely 21%, 26% and 31%. The alloy is then subjected to a hardness test, and a microstructure test. Having tested the used aluminum alloy piston with silicon carbide compared to the original piston. Vickers hardness test results on specimens of adding SiC 21% produced 166,017 VHN, SiC 26% produced 178,481 VHN, and SiC 31% yielded 204,538 VHN. While the original piston value as a comparison is 175 VHN. So that the addition is close to the hardness value on the original piston is SiC alloy 26%. Microstructure observation results showed the addition of SiC made the specimens increase in their hardness value. The increase is due to the many grayish black phases in the form of SiC and increasing SiC alloys, more and more phase grains and have a fairly large size.