Ultra-high pressure anti-slipping mold for discharging plasma sintering

Abstract

The invention discloses an ultra-high pressure anti-slipping mold for discharging plasma sintering. The ultra-high pressure anti-slipping mold is formed by combining parts formed and processed from high-purity graphite and parts formed and processed from a high-strength tungsten carbide alloy; an inner mold is embedded in the upper portion of a boss of the side wall of an outer mold, and the outermold wall is provided with a radial blind hole which is used for mounting of a thermocouple to monitor the temperature in real time. An upper inner pressure head and a lower inner pressure head are correspondingly embedded in the upper part and the lower part of the inner side wall of the inner mold, and a cavity formed between the upper inner pressure head as well as the lower inner pressure head and the inner mold is a sintering zone which is used for filling powder of a sintering testing piece. One ends of an upper cushion block and a lower cushion block are planes and abut against a lowerouter pressure head and an upper outer pressure head, and the other end faces of the upper cushion block and the lower cushion block are provided with disc-shaped bulges, and the disc-shaped bulges and the lower inner pressure head and the upper inner pressure head are symmetrically mounted in a fit mode. Under the premise that smooth electricity conducting is ensured, the mold can effectively improve the sintering pressure applied on a sample, and prevent relative slipping of the inner mold and the outer mold in the sintering process after the mold is used for a long time; and thus the production cost is reduced, and the production efficiency is improved.

Description

technical field [0001] The invention relates to the technical field of powder metallurgy sintering equipment, in particular to an ultra-high pressure anti-slip mold for spark plasma sintering. Background technique [0002] In recent years, nanocrystalline materials have aroused a research boom at home and abroad because of their excellent properties. However, due to limited preparation techniques, it is currently difficult to prepare large nanocrystalline bulk materials. In contrast, the technology of preparing nanocrystalline powder by high-energy ball milling is relatively mature, so the preparation of powder into bulk nanocrystalline materials by powder metallurgy has become a current research hotspot. At present, nanocrystalline bulk materials are mainly prepared by hot isostatic pressing (HIP), ultra-high pressure sintering (UPS) and spark plasma sintering (SPS). [0003] The spark plasma sintering method is to put metal powder into a mold made of graphite and other ma...

AI Technical Summary

Problems solved by technology

Although this mold can increase the pressure during sintering to a certain extent, since the indenter is still made of graphite, the pressure that can be increased is limited.

And if it is used for a long time, the gap between the inner and outer molds of the mold will gradually increase. During the sintering process, the inner and outer molds may slide relative to each other, which will cause the problem of the sample falling, which greatly reduces the service life of the mold and increases cost of sample preparation

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