Precipitation-hardened soft magnetic ferritic stainless steels

Abstract

A precipitation-hardened soft magnetic ferritic stainless steel comprises C: not more than 0.2 mass %, Si: 0.01-3.0 mass %, Mn: not more than 0.5 mass %, S: not more than 0.3 mass %, Cr: 12.0-19.0 mass %, Ni: 1.0-4.0 mass % and Al: 0.2-4.0 mass % and further contains at least one of Ti: less than 0.5 mass % and Zr: less than 0.3 mass % and the remainder being inevitable impurities and Fe, and has substantially a microstructure of a ferrite phase after a solution treatment and an aging treatment.

What is claimed is:  
     
         1 . A precipitation-hardened soft magnetic feiritic stainless steel characterized by comprising C: not more than 0.2 mass %, Si: 0.01-3.0 mass %, Mn: not more than 0.5 mass %, S: not more than 0.3 mass %, Cr: 12.0-19.0 mass %, Ni: 1.0-4.0 mass % and Al: 0.2-4.0 mass % and further containing at least one of Ti: less than 0.5 mass % and Zr: less than 0.3 mass %, and the remainder being inevitable impurities and Fe, and having substantially a microstructure of a ferrite phase after a solution treatment and an aging treatment.  
     
     
         2 . A precipitation-hardened soft magnetic ferritic stainless steel characterized by comprising C: not more than 0.2 mass %, Si: 0.01-3.0 mass %, Mn: not more than 0.5 mass %, S: not more than 0.3 mass %, Cr: 12.0-19.0 mass %, Ni: 1.0-4.0 mass % and Al: 0.2-4.0 mass % and further containing at least one of Ti: less than 0.5 mass % and Zr: less than 0.3 mass % and at least one of Nb: not more than 1.0 mass %, Mo: not more than 4.0 mass %, Cu: not more than 2.0 mass %, B: not more than 0.01 mass % and REM: not more than 0.1 mass %, and the remainder being inevitable impurities and Fe, and having substantially a microstructure of a ferrite phase after a solution treatment and an aging treatment.