FREE-CUTTING, CORROSION RESISTANT AND SOFT MAGNETIC STEEL FOR BAR OR PIPE WITH SUPERIOR TOUGHNESS

摘要

PURPOSE:To obtain a soft magnetic steel for a bar or a pipe with high toughness, superior corrosion resistance and machinability by prescribing the contents of C+N, Si+Al, 2Si+Al, Al, Ti, Cr, Mn, Pb, P and S. CONSTITUTION:Said soft magnetic steel for a bar or a pipe consists of, by weight, =0.02% C+N, =6% Si+Al, =3.5% Al, 0.10-0.60% Ti, 5-15% Cr, =0.40% Mn, 0.05-0.25% Pb, =0.040% P, =0.03% S and the balance essentially Fe. The toughness of the steel is improved without deteriorating the electromagnetic characteristics by combinedly adding said proper amounts of Cr, Si, Al, Ti and Pb and restricting the total amount of C and N to said very low value. At the same time, the corrosion resistance and machinability are also improved. When the iron core of a solenoid valve is made of the free-cutting, corrosion resistant and soft magnetic steel, the valve consumes less electric power than a valve having an iron core made of a conventional steel, and it shows superior electromagnetic characteristics.