ALLOYED TOOL STEEL, TOOL FOR PLASTIC FORMATION AND HARDENED BLANK Russian patent published in 2005 - IPC

FIELD: metallurgy, in particular, alloyed tool steels for manufacture of tools for plastic formation.

SUBSTANCE: alloyed tool steel contains, wt%: carbon 0.16-0.27; silicon 0.1-1.5; manganese 0.1-1.2; chromium 12.5-14.5; nickel 0.5-1.7; molybdenum 0.2-0.8; vanadium 0.1-0.5; nitrogen 0.06-0.13; possibly at least one of sulfur max. 0.15; calcium max. 0.01; oxygen max. 0.01; iron and unavoidable contaminants the balance. Total content of carbon and nitrogen satisfies the condition of 0.3≤C+N≤0.4. Plastic formation tool is manufactured from said steel. After hardening at temperature of 1,020-1,030 C followed by tempering at temperature of 200-250 C or at temperature of 500-520 C, steel for manufacture of said tool has microstructure with matrix consisting of tempered martensite and containing 0.3-1.0 vol.% of primarily settled carbon nitrides consisting substantially of M(C,N) carbon nitrides.

EFFECT: improved hardenability, plasticity and corrosion resistance of steel and, accordingly, tool manufactured from such steel.

15 cl, 7 dwg, 2 tbl