Method for producing annealing-free hot rolling S50C plate and strip

Abstract

The invention relates to a method for producing an annealing-free hot rolling S50C plate and strip, belonging to the technical field of hot rolled plates and strips. The invention adopts the technical scheme that austenite rolling is adopted in rough rolling, a deformation-induced ferrite rolling and warm rolling combined process is adopted in finish rolling, temperature in a rough rolling region is controlled to be 960-1150 DEG C, accumulated screwdown rate is more than 50%, an intermediate blank obtained by the rough rolling is cooled by water and then enters into a finish rolling mill group, opening rolling temperature of a finish rolling mill is 760-850 DEG C, finished rolling temperature of the finish rolling mill is 650-750 DEG C, the accumulated screwdown rate is more than 50%, cooling rate after rolling is controlled to be 0.1-25 DEG C / s, and coiling temperature is controlled to be 550-700 DEG C. The austenite rolling during rough rolling is carried out, thus austenite crystals are refined; the deformation-induced ferrite rolling and warm rolling during finish rolling are carried out, thus ferrite is excessively separated out, carbide is modified in a deformation process, plasticity and toughness of steel are improved, the aim of direct moulding while annealing is eliminated is achieved, and a spheroidizing process before cold forming is eliminated.

Description

technical field [0001] The invention relates to a production method of an annealing-free hot-rolled S50C strip, which belongs to the technical field of hot-rolled strips. Background technique [0002] S50C hot-rolled strips are usually cold-formed to manufacture mechanical parts such as disc shears and springs, and their carbon content is usually 0.47% to 0.53%. The hot-rolled disc shear steel S50C produced according to conventional rolling technology has pearlite in its microstructure in a lamellar shape, so time-consuming and energy-consuming spheroidizing annealing treatment is required before cold forming to make the steel The morphology of carbides in the alloy changes from flake to spherical. The spheroidizing annealing treatment of the background technology is not only complicated in process, long in production cycle, and consumes a large amount of energy, but also heat treatment is likely to cause waste products, increase metal consumption, and pollute the environme...

AI Technical Summary

Problems solved by technology

The spheroidizing annealing treatment of the background technology is not only complicated in process, long in production cycle, and consumes a large amount of energy, but also heat treatment is likely to cause waste products, increase metal consumption, and pollute the environment, with low production efficiency and high production cost. has become an urgent problem to be solved