2021 年 68 巻 5 号 p. 157-166
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 an electronic fuel injector, and PB permalloy components have been commercialized. However, Ni, an element of PB permalloy, is expensive material, making it difficult to produce the fuel injector component at a low cost. As a solution to this problem, we studied the magnetic properties of Fe-Cr-Si soft magnetic alloys by MIM process. These results revealed that the magnetic properties were improved by reducing Cr content. However, reducing Cr content is expected to reduce corrosion resistance of the alloys. In this study, Fe-Cr-Si-Mo alloy specimens containing Mo to improve corrosion resistance are manufactured by MIM process, and we investigated the magnetic properties and corrosion resistance. These results revealed that Fe-10Cr-3Si-2Mo alloy is a material with excellent magnetic properties and corrosion resistance.
