METHOD OF MANUFACTURE OF STEEL MONOSHEET ARMORED MEMBERS B 100 ST Russian patent published in 1999 - IPC

FIELD: metallurgical production of high- strength steels applicable in manufacture of armored members for means of armored protection of people, equipment and structures. SUBSTANCE: for manufacture of armored members, alloyed steel is taken with total content of carbon and nitrogen amounting to 0.45-1.05 wt.%, which is determined from relation C=0.45+0.03A %, where C is total content of carbon and nitrogen; A is thickness of armored members within interval of 0.5-20.5 mm. Steel melt of selected composition is subjected to solidification at rate of, at least, 1 mm/s. Castings are heated from temperature of not below 900 C to temperature of forging, and forged with reduction of, at least, 40% on two mutually perpendicular faces, then, they are subjected to homogenizing annealing, and further forging to reduce casting, first, by 30-50%, and, then, in three mutually perpendicular directions by, at least, 50-60%; annealing form forging heating within temperature interval from Ar₁ -50 C to Ar₁ -100 C, and intermediate cooling to shop ambient temperature; intermediate machining; hot rolling is carried out within temperature interval from Ar₃ +120 C to Ar₃ +40 C by alternating of rolling in longitudinal and transverse directions; annealing from rolling heating within temperature interval from Ar₁ -50 C to Ar₁ -100 C cooling down to finish rolling, which is effected with total reduction of 1-5%. After shaping of blanks of armored members, they are subjected to hardening with cooling to temperature from 100 C to -90 C and tempering within interval of 100- 250 C. EFFECT: higher resistance of armored members manufactured by claimed method to bullets with steel cores.