530 MPa-grade thin galvanized band steel and production method thereof

Abstract

The invention discloses 530 MPa-grade thin galvanized band steel and a production method thereof. The 530 MPa-grade thin galvanized band steel comprises, by weight, 0.08-0.12% of C, 0-0.06% of Si, 1.1-1.5% of Mn, 0-0.016% of P, 0-0.008% of S, 0.040-0.055% of Nb, 0.020-0.045% of Als, 0-0.007% of N, 0.015-0.030% of Ti, 0.0015-0.0045% of Ca, and the balance Fe. Converter and LF refining is conducted in a low nitrogen mode, LF refining, the acid-soluble aluminum content before LF refining calcium treatment is 0.025-0.045%, molten steel is clearly blown by bottom blowing argon after calcium treatment for 6-15 min, and refining is completed; and when refining is finished, the acid-insoluble aluminum content is less than or equal to 0.004 wt%, the ratio of the acid-insoluble aluminum content to the calcium content is less than or equal to 2.5, and in order to reach the ratio, calcium treatment is conducted. The 530 MPa-grade thin galvanized band steel meets the requirements of the surface quality level FB in GB2518 and EN10346.

Description

Technical field [0001] The invention belongs to the technical field of metallurgical plate production, and in particular relates to a 530MPa grade thin-gauge galvanized steel strip with a thickness of 0.9-2.5 mm and a production method thereof. Background technique [0002] With the growth of automobile production, people pay more and more attention to the emission of automobile exhaust. The application of high-strength steel in automobiles is conducive to reducing the weight of automobiles and reducing automobile exhaust emissions, and on the other hand, it also improves the safety of people in the car. Guarantee; more importantly, in order to ensure the corrosion resistance of automotive panels, the use of galvanized automotive panels is also increasing year by year. At present, the production methods for producing galvanized automobile sheets with tensile strength greater than 530MPa are mainly phase transformation strengthening methods such as dual-phase steel and multi-phase...

AI Technical Summary

Problems solved by technology

At present, the production method of galvanized automobile sheet with a tensile strength greater than 530MPa is mainly a phase transformation strengthening method such as dual-phase steel and multi-phase steel. The production method is characterized by adding martensite forming elements such as Cr and Mo, and utilizing phase transformation To improve the tensile strength of steel, this process is difficult to control, and the cost of Cr and Mo alloys added is high. At the same time, the rapid cooling capacity of galvanizing equipment is extremely high, which is not conducive to large-scale application

Images