Manufacturing method of age-hardened thin-strip casting low-carbon microalloyed steel strip

Abstract

The invention discloses a manufacturing method of age-hardened thin-strip casting low-carbon microalloyed steel strip. The method comprises the following steps of: 1) smelting, and continuously casting a thin strip, wherein the weight percents of the components are as follows: 0.01-0.25% of C, not more than 0.4% of Si, 0.6-2.0% of Mn, not more than 0.015% of P, not more than 0.01% of S, not more than 0.006% of N, not more than 0.008% of O, 0.0005-0.004% of B, 0.005-0.1% of Nb, 0.005-0.1% of V, 0.005-0.1% of Ti, and 0.05-0.5% of Mo, and the balance of Fe and unavoidable impurities, and the casting thickness in the dual-roller continuous casting machine is 1-5mm; 2) cooling the cast strip, wherein the cooling rate is more than 20DEG C/s; 3) hot-rolling at 1050-1250 DEG C, wherein the reduction rate is 20-50%, and the deformation rate is more than 20s-1; 4) cooling, wherein the cooling rate is 10-80DEG C/s; 5) reeling at 550-700 DEG C; 6) performing age-hardening treatment, wherein the age-hardening temperature is 500-800 DEG C, and the heating time is 0.1-30 minutes. The austenite online recrystallization of the cast strip after hot-rolling is realized, the obtained steel strip is provided with uniformly distributed bainite and acicular ferrite, the structure comprises nanoscale precipitation such niobium carbonitride, and a product has high strength and extensibility.

Description

technical field [0001] The present invention relates to a thin strip continuous casting process, in particular to a method for manufacturing an age-hardened thin strip continuous casting low-carbon micro-alloy high-strength steel strip. %, with excellent strong plasticity matching. Background technique [0002] At present, the production of low-carbon high-strength thin-gauge steel strip products containing microalloying elements such as Nb, V, Ti, and Mo is mainly realized through traditional hot rolling and cold rolling processes. However, there are some problems in the production by traditional hot rolling or cold rolling process. [0003] First of all, the traditional process is long, high energy consumption, many units and equipment, and high infrastructure costs, resulting in high production costs. [0004] Secondly, when using the traditional hot rolling process to produce micro-alloyed high-strength thin-gauge products containing micro-alloying elements such as Nb,...

AI Technical Summary

Problems solved by technology

This not only increases the investment cost, but also significantly increases the floor area of ​​the thin strip continuous casting and rolling production line, reducing the advantages of the production line

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