Corrosion Properties of the Fe-Cr-Based Soft Magnetic Alloys Fabricated by Metal Injection Molding

Abstract

Fe-Cr based soft magnetic alloy, which has excellent soft magnetic properties and practical corrosion resistance is required. SUS430L is one of the candidate Fe-Cr based alloys with soft magnetic property in stainless steels. To improve soft magnetic properties, sintering process is useful to make low Cr alloy by adding the pure iron powder to SUS430L powder. While, reduction of Cr content expected to deteriorate corrosion resistance of the alloys. To evaluate the effect of Cr content on mechanical and electrochemical properties of the soft magnetic alloys, sintered SUS430L based alloys with different Cr content were prepared using metal injection molding process. We carried out slow strain rate tensile (SSRT) test and open circuit potential (OCP) to evaluate their mechanical properties and electrochemical properties. The results of SSRT and OCP suggest that Cr content enhance stress corrosion cracking. OCP value was affected formation of passive film on elastic deformation and collapse of it on plastic deformation during SSRT test.