Powder metallurgy helical gear and preparation method thereof

Abstract

The invention provides a powder metallurgy helical gear which is formed by compressing the following power stocks in part by weight: 100 parts of iron powder, 1.8 to 2.0 parts of copper powder, 0.5 to 0.8 part of molybdenum powder, 0.1 to 0.3 part of cobalt powder, 0.8 to 1.2 part of nickel powder, 0.5 to 0.8 part of graphite powder, 0.1 to 0.3 part of modified wood ash, 0.2 to 0.6 part of rare earth ferrosilicon alloy, 0.1 to 0.3 part of paraffin, 0.1 to 0.2 part of ethylene bis stearamide, 0.1 to 0.3 part of celestite powder, 0.2 to 0.4 part of yttrium powder, 0.2 to 0.4 part of boron nitride, and 0.4 to 0.5 part of zinc oxide. When in preparation, mixing the powder stocks stepwise firstly, and obtaining the finished product helical gear through compressing and manufacturing, sintering, heat treatment and surface treatment. The produced powder metallurgy helical gear has the advantages that the helical gear is good in abrasion resistance, high in strength and rigidity, good in machinability, is corrosion resistant and less susceptible to breakage, and has a long service life.

Description

technical field [0001] The invention relates to the field of powder metallurgy, in particular to a powder metallurgy helical gear and a preparation method thereof. Background technique [0002] Powder metallurgy technology can produce parts requiring high dimensional accuracy and complex shapes in a shape very similar to the shape of the product, which can greatly reduce cutting costs. Therefore, powder metallurgy products are used in various fields as parts of various machines and devices. [0003] Generally speaking, after mixing powders for alloys such as graphite powder and lubricant powders such as stearic acid and paraffin into iron-based powders to form iron-based powder mixed powders, the iron-based powder mixed powders are filled in metal molds, and Press molding to manufacture iron-based powder compacts (compact powders) for powder metallurgy. Among them, the iron-based powder can be divided into iron powder (pure iron powder, etc.), alloy steel powder, etc. ...

AI Technical Summary

Problems solved by technology

However, in the existing powder metallurgy parts, due to the different proportions of various raw materials in the formula, it is difficult to ensure uniform mixing during mixing, resulting in uneven density of the pressed green body. After heat treatment, the overall density of the obtained parts is uneven. lead to poor mechanical properties