Method for improving iron powder forming property

Abstract

A method for improving an iron powder forming property belongs to the technical field of powder metallurgy forming. Pressed blank density can be increased by using good lubricating performance of sulfide. Iron powder and ferrous sulfide powder are mixed in a ball mill and annealed in a hydrogen furnace after being mixed evenly, and the ferrous sulfide is distributed on the surface of the iron powder evenly. In a pressing process, the ferrous sulfide has a lubricating effect, friction condition among powder particles is improved, the forming property is improved, and a blank with the density as 7.2g/cm<3>-7.6g/cm<3> can be obtained. The method has the advantages that the iron powder forming property is good, the blank with higher density can be obtained under low pressing pressure, loss of a grinding tool is reduced, simultaneously sulfur does not affect the performance of iron-based parts, and the process is simple and suitable for industrialized production.

Description

technical field [0001] The invention belongs to the technical field of powder metallurgy forming and provides a method for improving the formability of iron powder. Background technique [0002] Iron-based powder metallurgy parts are engineering materials with rapid development and great application potential. Because of their characteristics of material saving, energy saving, low-cost mass production, complex shapes and final precision parts, they are widely used in machinery, aviation, especially It is widely used in the automobile and motorcycle industries, and the common ones are pulleys, sprockets, gear hubs, cams, connecting rods, valve seats, etc. [0003] At present, the forming process of iron-based powder metallurgy parts is pressing. The density of the compact has a great influence on the final performance of the part. High compact density can obtain better mechanical properties. Therefore, how to increase the density of the compact has become an iron-based powder...

AI Technical Summary

Problems solved by technology

The commonly used method is to prepare high-purity, high-sphericity iron powder or add organic lubricants such as zinc stearate. Limited by the uniformity of the mixture and the limited lubrication performance, organic residues will affect the mechanical properties of the parts. The density of the compact is up to about 7.1~7.2g / cm3, but the production process of high-purity and high-sphericity iron powder is complicated and the cost is high

CN 101534979A patent document provides a kind of high compressibility iron powder and iron powder and powder magnetic core for powder magnetic core using the high compressibility iron powder. High-sphericity pure iron powder with an average number of crystal grains of less than 4 and an average hardness of less than 80 in terms of micro-Vickers hardness HV, and then pressed by adding lubricants such as zinc stearate, mixed metal soap, and amide wax , this method has high requirements on iron powder raw materials, complex production process and high cost