A new generation of non-uniform cemented carbide for mining-2

       According to the literature report, in the late sixties, the research progress of foreign mining-used hard alloys revealed two basic viewpoints: First, some scholars believe that the use of high-performance hard metals

The quality alloy should be uniform in structure, free of refractory phase grain aggregates and ensure the uniform distribution of the binder between the refractory phase grains, so as to prevent the formation of an extremely thin layer of fusion phase.

Second, other scholars believe that a much larger alloy filling density can be obtained through the method of matching the thickness of the hard phase tungsten carbide. At the end of the 1960s, the U.S. Golden Carbon Billion Company published

A patent for manufacturing non-uniform cobalt-bonded hard alloy. It is said that the percussion rock drill bit made of the alloy is used in the open mine and has obtained good results L7.

According to the preparation process, non-uniform cemented carbide can be divided into two types:

One is a heterogeneous alloy made by matching the thickness of the hard phase tungsten carbide; two, the high-cobalt and low-cobalt alloy mixtures are separately wet-milled and granulated separately. Evenly give up gold. In 1983, the Zhuzhou Cemented Carbide Plant Research Institute analyzed the United States

Country D res ser C o. The chemical composition and metallographic microstructure of H 10M mining cone drill teeth are found to be different in cobalt content from the top to the edge ring teeth, and the hard phase is thick and finely matched.

Uniform alloy. The H s ~ 1 l alloy produced by Japan's Sumitomo Electric Co., Ltd. is also a heterogeneous alloy with hard phase thickness matching. According to literature investigation and market information analysis, foreign mines have rejected the non-uniform hard joint barriers and are currently in the stage of promotion and application. On the basis of literature research, the preparation process and microstructure of the non-uniform hard compound for stripping have been systematically tested. The purpose is to find good impact resistance and high wear resistance, suitable for the development of modern high-efficiency rock drills. The required new generation of joint base series. Experiments have shown that the non-uniform alloy prepared by mixing two kinds of alloys of A and B, the mean free path of the cobalt phase is greater than that of the cobalt containing the same cobalt, which is made from only one tungsten carbide particle size range. The microscopic stress is the opposite. The experiment also showed that the non-uniform wide particle size distribution (bimodal distribution). In the final sintered product, a non-uniform microstructure is formed. Through indoor appraisal and rock drilling production, it is shown that the new generation of cemented carbide for mining has the high toughness of high cobalt alloy and the high wear resistance of low drill box. It is more resistant to impact, and its performance has reached the advanced level of similar foreign bit alloys.