A kind of 980mpa grade bainite-based q&p steel for automobile and its production method

Abstract

A 980MPa-grade bainite-based Q&P steel for automobiles and a production method, the chemical composition of which is calculated by mass percentage: C 0.24%-0.28%, Si 1.40%-1.60%, Mn 2.40%-2.50%, P≤0.020% , S≤0.0050%, AlS 0.020%~0.070%, N≤0.0060%, Nb 0.030%~0.05%, and the balance is Fe and other unavoidable impurities. Compared with the prior art, the invention has the beneficial effects of simplifying the production process and reducing the production cost while meeting the requirements of high strength and high elongation of the automobile body structural parts.

Description

technical field [0001] The invention relates to the field of steel manufacturing for automobiles, in particular to a 980MPa grade bainite-based Q&P steel for automobiles and a production method. Background technique [0002] At present, advanced high-strength steels are widely used in car bodies, such as Q&P980, TRIP980, DP980, and TWIP980. These steel types have been widely used in body B-pillars and door frame reinforcements, as well as more complex body structures such as front and rear longitudinal beams. pieces. While the application of advanced high-strength steel is becoming more and more extensive, problems such as forming difficulties accompanied by high strength are also emerging, and the requirements for cold stamping forming technology are relatively high. At the same time, as automobile factories continue to increase the strength requirements of automobile structural parts, the production process of the material itself will be more complicated, and the addition...

AI Technical Summary

Problems solved by technology

Using the heat treatment process of quenching and heating, high-strength steel with a strength level of 800MPa is produced, but the production process of this invention is too complicated to meet the needs of stable production

[0005] In summary, the traditional production process of cold-rolled high-strength Q&P steel for automobiles adopts the heat treatment process of quenching and heating, and its process flow is relatively complicated, which reduces the stability of production, and repeated heating and cooling of steel plates has become an obstacle to reducing production costs; at the same time In order to ensure the mechanical properties of the finished product, more microalloying elements are added, which further increases the production cost

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