Method of improving performance of iron-based powder metallurgy parts prepared by high velocity compaction

Abstract

A method of improving performance of iron-based powder metallurgy parts prepared by high velocity compaction belongs to the technical field of powder metallurgy. An optimization method that nanometer copper powder is used for replacing partial copper powder in iron-based mixed powder is adopted. The nanometer copper powder, the copper powder and iron powder are prepared in a glove box filled with high-purity argon according to a certain mass fraction, and fed into a charging barrel. The charging barrel is sealed, and put into a centrifugal drum machine to carry out mixing for a certain period of time, so that a uniform iron-based powder mixture is obtained. Zinc stearate acetone suspension is used as a die wall lubricant, and the iron-based parts are prepared by the high velocity compaction. The parts are sintered for a certain period of time under the protective atmosphere of hydrogen at the temperature of 1150-1280DEG C, so as to obtain iron-based products with high mechanical properties. According to the invention, the nanometer metal powder is combined with an advanced high velocity compaction technology, the iron-based powder metallurgy parts with high mechanical properties are successfully prepared, and the method has the advantages that the preparation process is simple, the cost is low, the production efficiency is high, the part density and the mechanical property are stable, the part sintering size precision is high, and the like.

Description

technical field [0001] The invention belongs to the technical field of powder metallurgy, and particularly provides a method for improving the performance of iron-based powder metallurgy parts prepared by high-speed pressing. technical background [0002] With the continuous development of powder metallurgy technology, powder metallurgy products have been involved in various fields, especially in the automobile industry, powder metallurgy products have played an indispensable role, and its application value has been widely valued. At present, the research on powder metallurgy products has moved towards the trend of mass production of high-performance powder metallurgy products. With the maturity and diversification of various powder metallurgy Based on powder metallurgy products with its high density and high performance characteristics to meet the increasing market demand. [0003] The development of high-density and high-performance iron-based powder metallurgy materials ...

AI Technical Summary

Problems solved by technology

The powder institute of Beijing University of Science and Technology has conducted comprehensive research in this area. Zhang Xiaohan published his master's degree thesis of University of Science and Technology Beijing in December 2012, "Technology Research on the Preparation of Iron-based Parts by High-speed Pressing Technology", and the iron-based mixed powder was pressed three times by high-speed pressing technology. The mechanical properties of the obtained powder metallurgy parts have been greatly improved, but the desired effect is still not achieved. , the minimum density of the powder metallurgy iron-based parts obtained by two pressings is 7.45~7.51g·cm -3 , the corresponding tensile strength is 500-700MPa, and the highest density reaches 7.58-7.625g·cm -3 , the corresponding tensile strength is 700-900MPa, compared with the previous powder metallurgy iron-based parts, the mechanical properties have been greatly improved, but the improvement of mechanical properties obviously depends on the increase of density, and has nothing to do with the choice of raw materials. There is still room for improvement in obtaining good mechanical properties from raw materials; Wu Kunpeng et al. applied for a patent in March 2011 "a low-temperature sintering method for high-performance iron-based powder metallurgy parts" by adding nano-copper powder to ordinary iron powder. The method obviously reduces its sintering temperature, but its iron-based powder forming does not use high-speed compression forming technology, and the raw material of iron-based powder parts is only a single ordinary iron powder, without adding alloy element powders such as nickel and molybdenum, and the mechanical properties of the parts are obtained. The performance is not high enough, the highest hardness is only 68.7HRB

Images