Electroslag remelting production method of high-strength high-plasticity TWIP (Twinning Induced Plasticity) steel

Abstract

The invention provides a production method of high-strength high-plasticity TWIP (Twinning Induced Plasticity) steel, and belongs to the technical field of metallurgy. The TWIP steel comprises 0.03%-0.08% of C, 2.0%-3.0% of Si, 20%-30% of Mn, 2.5%-3.5% of Al, the balance of Fe and a small amount of other alloying elements. The TWIP steel is smelted by adopting a slag system comprising 60-70% of CaF2, 20-30% of Al2O3 and 5-15% of CaO; a right amount of manganese metal or electrolytic manganese and aluminium powder are added to slag so as to solve the problems of easy oxidization and burning loss of volatile elements in the TWIP steel. Argon is used for protecting remelting at a flow rate of 20-40Nm<3> / h, so that the burning loss of aluminium is reduced; the refinement is carried out at a low melting rate, and the melting rate is controlled at 700-950kg steel / hour. In a feeding period, electric currents gradually decline, and the feeding time is greater than 1.5 hours. The production method has the advantages that by adopting the electroslag remelting method, cracks are prevented from occurring in a TWIP solidification process, the solidification structure and the segregation condition of the TWIP steel can be improved, and meanwhile, the cleanliness of the TWIP steel can also be obviously improved.

Description

technical field [0001] The invention belongs to the field of metallurgy technology, and relates to a production and control method of high-strength and high-plasticity TWIP (twin-induced plasticity) steel, which can obtain TWIP steel with qualified components, excellent internal metallurgical quality and excellent mechanical properties. Background technique [0002] TWIP steel is a kind of twinning induced plasticity steel (Twinning induced plasticity), which is an ideal structural material for safety, weight reduction and energy saving in automobiles, which integrates high strength, high plasticity and high strain hardening performance. [0003] Single-phase austenitic high manganese steel was patented by R.A. Hadfield as early as 1883. Later, Grassel's research showed that increasing the content of Mn and adjusting the content of Al and Si in the Fe-Mn-Al-Si alloy can obtain a steel structure with a single austenite structure, and the product of its tensile strength and el...

AI Technical Summary

Problems solved by technology

However, the TWIP steel electroslag process technology has not been reported in the relevant literature. The determination of the mold slag composition, the burning loss control of easily oxidized elements and volatile elements, and the control of the loose center of the electroslag final stage are the key issues in the development of this technology.

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