Method for producing titanium microalloyed Q355B hot-rolled strip steel under non-refining condition

Abstract

The invention relates to a method for producing titanium microalloyed Q355B hot-rolled strip steel under a non-refining condition. The method is characterized in that through converter blowing and steel ladle argon blowing, components of a ladle sample are controlled to meet the requirements that C is in the range of 0.15%-0.20%, Si is in the range of 0.06%-0.15%, Mn is in the range of 0.35%-0.55%, S is less than or equal to 0.030%, P is less than or equal to 0.030%, Als is in the range of 0.020%-0.030%, and Ti is in the range of 0.030%-0.050%. Through continuous casting of a thermal expansion type asbestos gasket and control of the heating temperature being 1220-1240 DEG C, the finish rolling starting temperature being 1065-1115 DEG C, the finish rolling temperature being 930-1030 DEG C, the finish rolling temperature being 840-880 DEG C and the curling temperature being 605-635 DEG C, ferrotitanium is added under the condition of no refining furnace, so that the alloying cost is reduced, the constant-speed yield of the titanium alloy is guaranteed, then the inclusion content is reduced, and the product quality is guaranteed.

Description

technical field [0001] The invention relates to a production process of strip steel, in particular to a production method of titanium microalloyed Q355B hot-rolled strip steel under non-refining conditions. Background technique [0002] Q355B is a low-alloy structural high-strength steel with good mechanical properties and welding properties. It is widely used in high-rise buildings and construction machinery and other fields. With the rapid development of the economy, the demand for Q355B in my country is increasing. At the same time The quality requirements for this product are getting higher and higher. [0003] The national standard specifically limits the weight content of some elements of Q355B, in which the C content is not more than 0.24%, Si is not more than 0.55%, Mn is not more than 1.6%, P is not more than 0.035%, S is not more than 0.035%, and Cr is not more than 0.3% %, Ni is not more than 0.3%, Cu is not more than 0.4%, and N is not more than 0.012%. The trad...

AI Technical Summary

Problems solved by technology

Although the above operations can reduce the cost of alloying, the amount of titanium-containing materials such as titanium-iron wire, titanium-silicon-calcium composite cored wire is still relatively large, and the yield of titanium alloy elements is unstable and low under non-refining conditions.

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