Manufacturing method of titanium micro-alloyed steel continuous casting heavy slab

Abstract

The invention provides a manufacturing method of titanium micro-alloyed steel continuous casting heavy slab and the method comprises the following steps: firstly, obtaining refined liquid steel with the following mass percentage ratio: more than 0 and less than or equal to 0.005 of C, more than 0 and less than or equal to 0.004 of N, more than 0 and less than or equal to 0.03 of Si, 0.10-0.20 of Mn, more than 0 and less than or equal to 0.018 of P, more than 0 and less than or equal to 0.015 of S, 0.02-0.06 of Al, more than 0 and less than or equal to 0.070 of Ti, more than 0 and less than orequal to 0.002 of O, more than 0 and less than or equal to 0.05 of Cr, more than 0 and less than or equal to 0.07 of Ni, more than 0 and less than or equal to 0.07 of Cu, more than 0 and less than orequal to 0.020 of Mo, and the balance Fe and unavoidable impurity; secondly, continuously casting the liquid steel into heavy slab, blowing argon to protect in the whole course of casting, controlling the superheat degree of the liquid steel between 10 and 35 DEG C with the conical degree of a crystallizer being 0.8-0.9% / m, using a carbon-free mold powder, wherein, the thickness of the liquid slag layer of the slag powder is more than or equal to 15mm, the average heat flow of broadside copper plate of the crystallizer is 1.45-1.55MW / m<2> and the average heat flow of the side surface copper plate is 1.15-1.25MW / m<2>. The heavy slab manufactured by the method of titanium micro-alloyed steel continuous casting heavy slab has no surface longitudinal cracks.

Description

technical field [0001] The invention relates to a method for manufacturing a titanium micro-alloy steel continuous casting thick slab. Background technique [0002] The automobile industry has always been the pillar industry of the economy in developed countries, and it is also an important industry in some developing countries. Since 2001, with the rapid development of my country's automobile industry, the demand for automobile steel has increased significantly. At present, the steel used in automobiles is still dominated by steel plates, of which the weight of steel plates for cars accounts for about 50% of the total weight of cars. [0003] With the continuous improvement of the requirements for the use of cars and the development of car manufacturing technology, from the perspective of stamping performance, the steel plates for cars have been represented by the first generation of stamping steel represented by low-carbon boiling steel and low-carbon aluminum-killed stee...

AI Technical Summary

Problems solved by technology

[0011] In order to achieve the above purpose, and solve the problems of continuous casting breakout accidents and continuous casting waste products caused by defects of Ti microalloyed IF steel continuous casting thick slab surface longitudinal cracks, continuous casting productivity and continuous casting slab quality, and increase production costs, at the same time In order to solve the problems that the longitudinal cracks on the surface of such continuous casting thick slabs evolve into steel plate surface defects in the subsequent process, and limit the increase of productivity in the corresponding process and the increase of defective products, the present invention mainly adopts the chemical composition and thick slab continuous casting process system. Reasonable matching to eliminate longitudinal cracks on the surface of Ti microalloyed IF steel continuous casting thick slab