Preparation method for diamond particles deposited with WC/W (wolfram carbide/wolfram) composite coating on surfaces

Abstract

The invention discloses a preparation method for diamond particles deposited with a WC / W (wolfram carbide / wolfram) composite coating on the surfaces. According to the preparation method, the WC / W nano-composite coating is synthesised on the surfaces of the diamond particles by realizing a primary treatment via a dual-cathode plasma sputtering deposition method, and WC in the coating is formed via an interface in-situ reaction between W and the surfaces of the diamond particles during a dual-cathode plasma sputtering deposition process. According to the preparation method disclosed by the invention, the bonding strength and a holding force between the diamond particles and a metal binder, and the compressive strength of the diamond particles are obviously improved. In addition, the WC / W nano-composite coating deposited on the surfaces of the diamond particles has a protective effect on the diamond particles, thus preventing diamond from being oxidized and graphitized during high-temperature sintering and high-temperature grinding processes. The WC / W nano-composite coating in the preparation method disclosed by the invention is mainly suitable for manufacturing a diamond tool by taking a W-Co hard alloy as a matrix, and the diamond tool obtains a high exposure, thus improving the grinding sharpness and the machining efficiency of a grinding tool, and obviously prolonging the service life of the grinding tool.

Description

technical field [0001] The invention relates to diamond particles and belongs to the new technical field of diamond particle surface coating. The invention is especially suitable for diamond tools based on W-Co cemented carbide. It mainly involves double-cathode plasma sputtering deposition technology, interface reaction in-situ synthesis and types of deposition materials. Background technique [0002] Due to a series of excellent physical and chemical properties such as high hardness, high strength, high wear resistance and small linear expansion coefficient, diamond has been widely used in the field of grinding processing. For example, it can manufacture a variety of tools such as knives, grinding wheels, Abrasives, etc. Diamond tools are usually made of diamond particles as cutting materials, with the aid of binders and other auxiliary materials with certain shapes, properties and uses. Due to the characteristics of diamond itself, it is not infiltrated with convention...

AI Technical Summary

Problems solved by technology

Ordinary physical vapor deposition includes thermal evaporation plating, magnetron sputtering plating, ion plating, etc. There are complex processes, a small amount of single plating, and only physical adhesion between the plating layer and the diamond after plating without forming carbides with the diamond surface, etc. The problem is that it is difficult to bond a large area of ​​compounds in a short time of hot pressing in tool manufacturing, so the effect of using it is not obvious

However, the simple metal powder coating chemical vapor deposition and salt bath coating methods, the diamond is heated to more than 850°C during the coating process, even under high vacuum conditions, the strength of the diamond will be significantly reduced, and the industrial application value will be lost.

Vacuum micro-evaporation plating technology, which is widely used at present, also requires high deposition temperature, and the types of plating are limited (only limited to Ti plating), and the raw materials used contain certain toxic elements such as titanium trichloride, which is easy to pollute the environment.

Images