A preparation process of transition metal carbide powder and transition metal carbide-nitride composite powder

Abstract

The invention discloses a preparation process of transition metal carbide powder and transition metal carbide-nitride composite powder. The present invention uses a ball milling method to mix a transition metal with a certain amount of organic solvent containing carbon or carbon and nitrogen at the same time. After ball milling for a certain period of time, transition metal carbides or transition metal carbides with an average grain size of less than 50nm are obtained. The nitride composite powder contains a certain amount of transition metal hydride nano powder. The prepared powder is heat-treated under vacuum (<1Pa) or argon environment to obtain transition metal carbide or carbide-nitride composite powder, and the transition metal grain size distribution of 50-900nm is prepared by controlling the heating rate and heat treatment time. For metal carbide powders and transition metal carbide-nitride composite powders, the carbon and nitrogen contents varied with the ball milling time and the amount of organic solvent. The invention has simple process and is easy to produce, and can be used for preparing high-performance metal ceramics.

Description

Technical field [0001] The present invention is in the field of powder metallurgy, in particular to a transition metal carbide and transition metal carbide powder - Preparation of a composite nitride powder. Background technique [0002] Transition metal carbides, nitrides having high strength and hardness, as a binder metal can be used to prepare the cermet, widely used in metal cutting, mineral extraction, producing wear member. Transition metal compounds such as carbon TaC, ZrC, HfC, NbC, TiC and the like more than a melting point of 3000 deg.] C, and are ultra high temperature structural materials comprising a high temperature oxidation resistance, can accommodate a long time hypersonic flight, atmospheric re-entry, and rocket propulsion systems extreme environments, for aircraft nose cone, wing leading edge, and a nuclear reactor and other critical engine components. [0003] Transition metal carbides, nitrides synthetic preparation include reduction, direct carbon / nitridi...

AI Technical Summary

Problems solved by technology

These methods have their own limitations. The traditional reduction method and direct carbon / nitridation method usually need to be carried out at a higher temperature (1600-2200 ° C), and the prepared powder particles are coarse and uneven; the self-propagating combustion synthesis method It is difficult to control the preparation process and the uniformity of grains; the vapor deposition method is suitable for the situation with low output requirements; the mechanical alloying method is the method of using ball milling, through the contact between the ball and the ball and between the ball and the ball mill. The collision causes plastic deformation, work hardening and crushing of the powder particles. After the particles are refined, the surface activity increases. As the impact time of the grinding ball increases, diffusion reactions occur between atoms

In the invention patent application CN102249231A, carbon-containing organic solvents and transition metals are used as raw materials, and nano-transition metal carbides are prepared by ball milling. The average grain size is less than 20nm, but the impurity content is relatively high, and the performance is not ideal

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