FIELD: mining.
SUBSTANCE: drill bit includes housing made mostly from untreated composite material "matrix-particles" and having external surface. At least a part of housing surface is covered with abrasive wear-resistant material. At that, this material is obtained by means of application of composition containing: matrix material which is about from 2 to 5 pts. wt. per 10 parts of materials ready for application, containing at least 75 wt % of nickel, with fusing temperature less than about 1460°C; lots of sintered grains of tungsten carbide - 10 mesh by ASTM being in fact distributed at random on matrix material and making about from 3 to 5.5 pts. wt. of composition, at that each sintered grain of tungsten carbide contains lots of tungsten carbide particles bonded by bonding alloy with fusing temperature higher than about 1200°C; and lots of cast grains of tungsten carbide -18 mesh by ASTM, being in fact distributed at random on matrix material and making less than about 3.5 pts. wt. of composition.
EFFECT: increasing drill bit strength and its fracture resistance.
21 cl, 24 dwg
