METHOD FOR PRODUCTION OF HARDENED REINFORCING BAR OF PERIODIC PROFILE Russian patent published in 2016 - IPC C21D8/08 B21B1/18 

FIELD: metallurgy.

SUBSTANCE: to increase stability and qualitative properties of reinforcing bar of periodic profile of method for production of hardened reinforcing bar of periodic profile from low-carbon and alloyed steel classes strength 450-600 N/mm² with diameter of 6-20 mm, which includes making of steel containing carbon 0.16-0.35 wt%, hot rolling to produce reinforcement blank periodic profile of the specified size, having the yield strength is not less than 0.75 and ultimate tensile strength not less than 0.95 of class of strength of ready reinforcing bar, total uniform elongation at maximum load of not less than 8 % at ratio of ultimate strength rupture to yield point is not less than 1.2, strip reinforcement billet in coils and its cold hardening by alternating-sign bending effect, which is performed at drawing reinforcement workpiece through a system of rollers to allow accumulation non-monotonic deformation from stretching, compressing and bending to value of residual extract 1.03-1.08.

EFFECT: higher stability and quality factors of reinforcing bar of periodic profile.

1 cl, 3 tbl, 1 ex