| 摘要 |
FIELD: metallurgy. SUBSTANCE: method consists in the following: steel is melted and ingots are produced which are subjected to heat treatment by double normalization. It consists in that ingots initially are heated to temperature of 920-930 C and held at this temperature for 3-3.5 h with subsequent cooling in the air down to 200 C, and then repeatedly heated up to 870-880 C and held at this temperature for 2.5-3 h with subsequent cooling in the air down to 20 C. In this case, use is made of steel which contains ingredients in the following ratio, wt.-%: carbon, 0.20-0.40; manganese, 0.90-1.50; silicon, 0.17-0.40; chromium, 1.20-1.80; nickel, 0.30-0.60; copper, 0.20-0.40; vanadium, 0.15-0.30; boron, 0.001-0.01; aluminum, 0.02-0.06; iron, the balance. EFFECT: higher efficiency. 1 tbl
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