| 摘要 |
A mining or drilling tool which has a region subject to excessive wear is hardfaced on such region with sintered chromium carbide particles metallurgically bonded on the tool by a steel matrix which is alloyed with the particles at the interfaces therebetween. The particles are in a size range of 10 to 60 mesh and are present in an amount for effective abrasion resistance. The particles are comprised of grains of chromium carbide having an average size in the range of 0.5 to 25 microns disposed in a binder comprising a major portion of nickel. Minor portions of grain growth inhibitors, particularly, tinanium carbide and molybdenum carbide, are preferably components of the carbide particles so as to inhibit growth of the chromium carbide grains to be such that such grains have an average size in the range of 0.5 to 15 microns. The particles are preferably coated, prior to being applied as the hardfacing, with one or more materials such as ferrosilicon, ferromanganese, ferromolybdenum, nichrome and others identified below, to limit the alloying of the particle per se with a steel matrix, to improve the matrix, and to improve the welding characteristics of the hardfacing materials. There is also provided material comprising discrete particles as above described which are useful in forming the hardfacing material on the tool.
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