Low-temperature and high-toughness hot rolled H-shaped steel with yield strength of 550 MPa and preparation method thereof

Abstract

The invention discloses low-temperature and high-toughness hot rolled H-shaped steel with the yield strength of 550 MPa and a preparation method thereof. The low-temperature and high-toughness hot rolled H-shaped steel with the yield strength of 550 MPa is prepared from the following chemical components according to weight percent (%): 0.10% to 0.16% of C, 0.25% to 0.45% of Si, 0.70% to 1.55% of Mn, less than or equal to 0.030% of P, less than or equal to 0.025% of S, 0.045% to 0.08% of V, 0.008% to 0.012% of N and the balance of Fe and inevitable impurities. The production process of the steel comprises the following steps of continuous casting billet heating, rough rolling, universal rolling, saw cutting to a length and heat treatment. According to the low-temperature and high-toughnesshot rolled H-shaped steel and the preparation method, the components are rolled by adopting a conventional process, then the saw cutting to the length is performed, the production process of completequenching and tempering is adopted to the H-shaped steel, finally, tempered sorbite, bainite and fine carbide which is dispersed on the tempered sorbite and the bainite are obtained in the H-shaped steel, the yield strength of the H-shaped steel is not less than 550 MPa, the average longitudinal impact work at -60 DEG C is greater than 50 J, and the low-temperature and high-toughness hot rolled H-shaped steel has low ductile-brittle transition temperature.

Description

technical field [0001] The invention belongs to the technical field of metallurgy. Specifically, the invention relates to a low-temperature high-toughness hot-rolled H-shaped steel with a yield strength of 550 MPa and a preparation method thereof. Background technique [0002] In major national infrastructure projects, further emphasis will be placed on energy conservation, emission reduction and lightweight transportation equipment, to accelerate the green transformation and upgrading of the manufacturing industry, and to promote the development of steel, petrochemical, construction machinery, light industry, textile and other industries to the high end of the value chain. To this end, it is necessary to further increase the research intensity of steel materials, and devote ourselves to the development of new, high-strength, toughness, lightweight steel materials, reduce the consumption of energy and resources, and promote sustainable economic and social development. Moreov...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a low-temperature high-toughness hot-rolled H-shaped steel with a yield strength of 550 MPa, which can completely solve the stability and consistent production problems of high-strength, low-temperature and high-toughness hot-rolled H-shaped steel comprehensive performance requirements, and meet the specific fields. The demand for high-performance products fundamentally solves the problem that the hot-rolled H-beams in the production line of existing process equipment cannot simultaneously meet the requirements of high strength, high toughness and uniform cross-sectional properties

Images