Spark plasma sintering manufacturing technology for high-rigidity polycrystalline diamond drawing die

Abstract

The invention discloses a spark plasma sintering manufacturing technology for a high-rigidity polycrystalline diamond drawing die. A bushing is obtained by carrying out spark plasma sintering on metal powder, the vacuum degree is 2-8 Pa, the initial pressure is 20-30 MPa, after the temperature is increased to 300-350 DEG C with the rate of 80-100 DEG C / min, the pressure is reduced to 10-20 MPa, after the temperature is increased to 420-450 DEG C with the rate of 50-80 DEG C / min, the pressure is reduced to 8-10 MPa, after the temperature is increased to 500-520 DEG C with the rate of 30-50 DEG C / min, the temperature is increased to 550-570 DEG C with the rate of 20 DEG C / min, the temperature and the pressure are kept for 30-50 seconds, and the drawing die is obtained through cooling. In the spark plasma sintering process, shock waves, electrons and ions generated by pulse discharge can purify and activate powder, particles can be subjected to the comprehensive action of ion discharge, electric conduction heating and pressurizing at the same time, the activation energy is reduced, the sintering time is shortened, and the growth of grains is restrained; the nucleation energy can be reduced through pulse current, the nucleation rate is increased, and fine tissue is obtained. According to the spark plasma sintering manufacturing technology, a novel metal powder formula for the bushing and the spark plasma sintering technology are adopted, and therefore the high-strength, high-rigidity and high-density die is obtained.

Description

technical field [0001] The invention relates to the technical field of wire drawing dies, in particular to a spark plasma sintering manufacturing process of a high-hardness polycrystalline diamond wire drawing die. Background technique [0002] In metal pressure processing, the metal is forced to pass through the mold under the action of external force, the metal cross-sectional area is compressed, and the tool that obtains the required cross-sectional area, shape and size is called a wire drawing die, which is a kind of wire drawing die. From thick to thin, the tool gradually reaches the size required by people. It is composed of two parts: the mold sleeve and the mold core. During use, the mold will be damaged to varying degrees due to the effect of drawing. Good quality molds It is very important to improve the production efficiency of the enterprise and reduce the cost of the enterprise. In order to reduce the cost, obtain stable and long-term drawing, accurate size, and...

AI Technical Summary

Problems solved by technology

In the initial stage of sintering, the DC pulse voltage is used to generate high-temperature plasma between the particles, and the surface of the sintered material is cleaned, activated and uniformly heated, which helps to form a homogeneous and high-performance sintered body. The sintered material in the mold is heated by electricity, which has high thermal efficiency and can obtain extremely fast heating speed, thereby effectively shortening the sintering time, and at the same time, it is also conducive to maintaining the microstructure of the raw material and obtaining a sintered material with excellent performance. Underused in the die-inserting process

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