Effects of Cr and Si Contents on the Magnetic Properties of Fe-Cr-Si Soft Magnetic Alloys by MIM Process

Abstract

An electronic fuel injection system of automobiles have been commercialized at the end of 1960’s, they have been adopted as environmental measures for many automobiles and motorcycles. In recent years, metal injection molding (MIM) has been adopted as a process for manufacturing a solenoid valve which is a component of electronic fuel injector, and has been commercialized using PB permalloy. However, Ni that is an element of PB permalloy is expensive material, there was a problem that it is difficult to produce the product at low cost. As a solution to this problem, we can use Fe-Cr alloys, although there are few studies on Fe-Cr alloys by MIM process. In addition, when this materials are used in an alternating magnetic field, there is a problem that core loss increases in high frequency range. In this study, we made MIM specimens using Fe-Cr-Si alloy powders containing Si in addition to Cr and investigated the influence of Cr and Si contents on the magnetic properties. These results revealed that high performance soft magnetic material can be obtained by setting the Si content 3% and reducing the Cr content.