Manganese and boron series low-carbon microalloy high-strength non-quenched and tempered steel and production method thereof

Abstract

The invention discloses manganese and boron series low-carbon microalloy high-strength non-quenched and tempered steel and a production method thereof. The non-quenched and tempered steel comprises the following chemical components in percentage by weight: 0.17 to 0.25 percent of C, 0.80 to 1.20 percent of Si, 1.60 to 2.50 percent of Mn, 0.08 to 0.15 percent of V, 0.015 to 0.10 percent of Nb, 0.01 to 0.06 percent of Ti, 0.015 to 0.05 percent of Al, 0.0005 to 0.005 percent of B and the balance of Fe and inevitable impurities, wherein the total percentage of impurity elements is less than 0.05 percent. Elements, such as N, RE, Ca, Zr and the like, which are not easy to control in a smelting process, are not required to be added into the steel, and a quenching and tempering procedure is eliminated, so that the production process is simplified, the production efficiency is improved, and the production cost is reduced.

Description

technical field [0001] The invention belongs to the field of alloy steel, and mainly relates to a manganese-boron low-carbon micro-alloy high-strength non-quenched and tempered steel and a production method thereof. Background technique [0002] In recent years, with the rapid development of the automobile industry, the demand for steel for auto parts is increasing, and the performance requirements are also getting higher and higher. 35CrMo, 40CrMnMo, etc. are widely used in automotive shaft parts. Such shaft parts must be quenched and tempered before they can be used. The performance indicators are required to reach Rm≥980MPa, R p0.2 ≥785MPa, A 5 ≥10%, Z≥45%, this process has high energy consumption and many processes, resulting in high production cost, and sometimes defects such as deformation, cracking, oxidation and decarburization are unavoidable. Non-quenched and tempered steel has been paid attention to by countries all over the world because of its advantages of si...

AI Technical Summary

Problems solved by technology

35CrMo, 40CrMnMo, etc. are widely used in automotive shaft parts. Such shaft parts must be quenched and tempered before they can be used. The performance indicators are required to reach Rm≥980MPa, R p0.2 ≥785MPa, A 5 ≥10%, Z≥45%, this process has high energy consumption and many processes, resulting in high production costs, sometimes inevitable defects such as deformation, cracking, oxidation and decarburization

Another example is that Chinese Patent Publication Nos. CN1477226A and CN101597716A require the addition of one or more alloying elements such as RE, Ca, Zr, etc. in the steel, which makes the manufacturing process complicated and increases the production cost.

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