Non-quenched steel for camshafts and preparation method of non-quenched steel

Abstract

The invention belongs to the technical field of automobile steel and particularly relates to non-quenched steel for camshafts and a preparation method of the non-quenched steel. The steel is preparedfrom the chemical components in percentage by mass: 0.42%-0.49% of C, 0.30%-0.60% of Si, 1.00%-1.50% of Mn, 0.06-0.13% of V, 0.035%-0.075% of S, less than or equal to 0.035% of P, less than or equal to 0.30% of Cr, less than or equal to 0.30% of Ni, less than or equal to 0.30% of Cu, 0.010%-0.040% of Alt, less than or equal to 15 ppm of [O], and the balance Fe and inevitable impurities, specifically, C+Si/6+Mn/4.5+1.8*V is equal to 1-1.1. Electric furnace smelting and LF refining are adopted, desulfuration, then sulfuration and proper calcium treatment process are adopted in the refining process, and Mn/S is controlled. The vacuum treatment time of the steel is longer than or equal to 12 minutes, and the soft blowing time is longer than or equal to 20 minutes. A casting blank is cast through continuous casting, the pulling speed and the superheat degree are controlled, and the continuous casting of twelve furnaces or more is achieved. The heating and soaking temperature, the heating time, the initial rolling temperature, the final rolling temperature, the cooling speed and the like are controlled in the rolling process, and finally, peeling and flaw detection are carried out, so that high-quality round steel is obtained; and the round steel can meet the requirement for direct cutting processing.

Description

technical field [0001] The invention belongs to the technical field of steel for automobiles, and in particular relates to a non-quenched and tempered steel for a camshaft and a preparation method thereof. Background technique [0002] The camshaft is a part of the piston engine. Its function is to control the opening and closing of the valve. The camshaft rotates at a high speed and needs to bear a large torque. Therefore, the camshaft has high requirements for strength and support; The cam bearing is subject to periodic impact loads, the contact stress between the cam and the tappet is very large, and the relative sliding speed is also high, so the wear of the cam working surface is serious, and the camshaft journal and the cam working surface should be relatively heavy. In addition to high dimensional accuracy, small surface roughness and sufficient rigidity, it should also have high wear resistance and good lubrication, which occupies a very important position in the des...

AI Technical Summary

Problems solved by technology

[0003] At present, there are few patent applications for camshaft steel and its production method in the prior art

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