Gear thermal precision forging machining process adopting carburizing steel 20CrMnTi as material

Abstract

The invention discloses a gear thermal precision forging machining process adopting carburizing steel 20CrMnTi as a material. The process especially comprises the following steps of: upsetting prolonging, blank manufacturing, die forging, burring, forging aftert-reatment (including quenching, tempering thermal treatment; accomplishing the gear thermal treatment through nitriding, surface quenching and normalizing; and finally carrying out sand blasting to remove a scale cinder and the surface acid treatment), and tooth profile cold-finish. By utilizing the process, the fogging process is simplified, the procedures are reduced; the processed product is good in quality; the production in scale can be realized so as to achieve the purposes of good quality, material conservation, energy conservation and time saving; and meanwhile the service life of a mold can be improved greatly, so that the wear resistance of the manufactured gear is enhanced greatly; the gear point-corrosion spalling is overcome; the strength is improved greatly; the service life is prolonged; and the cost is reduced.

Description

technical field [0001] The present invention relates to gears, and materials therefor. Especially a gear hot precision forging process using carburizing steel 20CrMnTi as material. Background technique [0002] For gears processed directly from rolled bars, the normal stress at the root of the working tooth is perpendicular to the direction of the fiber structure, and the mechanical properties of the gears are poor. However, after upsetting, the gears are processed by cutting the bars, and the fiber structures are bent. It is radial, and the normal stress at the root of the gear is parallel to the direction of the fibrous tissue, so the mechanical properties are much better. At the same time, in general gear processing, steel and iron are mostly used as processing materials. However, steel and iron gears generally have many complex processes, long production cycle, low production efficiency and relatively high production cost. Due to some shortcomings, gears of other mater...

AI Technical Summary

Problems solved by technology

At the same time, in general gear processing, the processing materials are mostly steel, iron, etc., but the general processing procedures of steel and iron gears are complex, the production cycle is long, the production efficiency is low, and the production cost is relatively high.

Due to some shortcomings, gears of other materials can only be used in specific occasions, and the common process for processing gears is: the traditional processing methods generally have the following methods: one is to forge the blank and then use cutting to process the teeth , this method is not only labor-intensive and material-intensive, but also has a tool relief groove at the root of the tooth, which affects the strength of the combined tooth; another method is to form the tooth and the main body by electron beam welding, but there is a phenomenon of stress concentration in this way

This leads to product quality defects, often causing accidents in the application

In recent years, although some people have proposed the processing method of casting extrusion forming, the tooth shape does not need to be cut, but at present, cold extrusion is mostly used, the general structure particles are relatively coarse, the mechanical properties are poor, and the service life is short, which leads to the preforming process. In the middle, the deformation resistance of the material is large, resulting in a reduction in the life of the mold, which cannot meet the requirements of industrial production