Steel Material for Soft Magnetic Part, Soft Magnetic Part, and Method for Producing Soft Magnetic Part

• Main Authors: Egashira, Makoto, Sueno, Hidekazu, Matsumoto, Hitoshi
• Format: Patent
• Language: English
• Published: 31.10.2019
• Subjects: ALLOYS; BASIC ELECTRIC ELEMENTS; CHEMISTRY; ELECTRICITY; FERROUS OR NON-FERROUS ALLOYS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUSMETALS OR ALLOYS; INDUCTANCES; MAGNETS; MAKING METAL MALLEABLE BY DECARBURISATION, TEMPERING OR OTHERTREATMENTS; METALLURGY; METALLURGY OF IRON; MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES; TRANSFORMERS; TREATMENT OF ALLOYS OR NON-FERROUS METALS

Provided is a steel material for a soft magnetic component having excellent properties for cold working, excellent magnetic characteristics after magnetic annealing, and high fatigue strength. The steel material for a soft magnetic component according to the present invention has a chemical composition containing, by mass%, C: 0.02-0.13%, Si: 0.005-0.50%, Mn: 0.10-0.70%, P: 0.035% or less, S: 0.050% or less, Al: 0.005-1.300%, V: 0.02-0.50%, and N: 0.003-0.030%, the balance F and impurities. The average crystal particle size of the ferrite grains in the steel material for the soft magnetic component is 5-200 µm. Furthermore, in the ferrite grains, the quantity Sv (quantity/mm2) of precipitates having a circle equivalent diameter of 30 nm or larger satisfies expression (1). Expression (1): Sv ≤ 10V × 7.0 × 106 (1), where V in expression (1) is substituted with the V content (mass%) in the steel material for the soft magnetic component.