Manufacturing method of high wearproof gear steel

Abstract

The invention relates to a manufacturing method of high wearproof gear steel. The manufacturing method comprises the following steps: 1, smelting, wherein molten steel comprises the following components: 0.15-0.60% of C, 0.50-1.3% of Si, 0.50-1.2% of Mn, 0.60-1.5% of Cr, equal to or less than 0.030% of P, equal to or less than 0.035% of S, 0.010-0.050% of Al, 0.008-0.025% of N and the balance of Fe; 2, pouring: pouring molten steel into steel billets; 3, rolling: after heating the steel billets, rolling the steel billets in a single-phase region at the initial rolling temperature of 980-1100 DEG C, sequentially carrying out intermediate rolling, pre finish rolling and finish rolling, during the rolling process, controlling cooling, after intermediate rolling, carrying out spraying coolingon the steel billets, after pre finish rolling, carrying out spraying cooling on the steel billets once more, then, carrying out KOCKS finish rolling, and controlling the finishing temperature to be 780-900 DEG C to obtain an unstable austenite; and 4, cooling: carrying out blast cooling the steel billets on a cooling bed, controlling the average cooling rate to be 40-80 DEG C / min and the final cooling temperature to be 300-480 DEG C, after final cooling, carrying out air cooling on the material to the room temperature, and in the cooling process, converting the austenite into ferrite and pearlite. After carburizing, quenching and tempering, the rolled steel has excellent wear resistance.

Description

technical field [0001] The invention relates to a method for manufacturing wear-resistant steel, in particular to a method for manufacturing wear-resistant steel with relatively high silicon content. Background technique [0002] Recently, with the development needs of industries such as automobiles, improving the design wear life of gears, increasing the stability and life of operating equipment, thereby improving efficiency and reducing costs has become one of the important development directions of the industry. From the point of view of gear design, it is required that the surface has high hardness to improve wear resistance, and the core has certain toughness. Gear steel is usually designed with medium and low carbon to ensure the toughness of the core, and one or more alloying elements of Cr, Mo, V, B are added to improve the hardenability of the material. And during the subsequent heat treatment, the surface of the material is carburized (actually, carburizing, nitri...

AI Technical Summary

Problems solved by technology

However, silicon is an easily oxidizable element, and it is easy to segregate at the grain boundary. In the traditional carburizing heat treatment process, it is easy to cause the grain boundary oxidation of silicon and deteriorate the performance of the gear.

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