Tungsten carbide powder (WC) is the main raw material for the production of cemented carbides. Known as, tungsten carbide powder black hexagonal crystal, metal luster, hardness similar to diamond, is a good conductor of electricity and heat. Melting point 2870 degrees, boiling point 6000 degrees, relative density 15.63 (18 degrees). Tungsten carbide is insoluble in water, hydrochloric acid and sulfuric acid. Pure tungsten carbide is fragile. If mixed with a small amount of metals such as titanium and cobalt, brittleness can be reduced. Tungsten carbide, used as a cutting tool for steel, is often added with titanium carbide, tantalum carbide, or a mixture of them, to enhance the ability to resist explosion. Tungsten carbide is chemically stable.

A method for preparingcast tungsten carbide powder is characterized by the following steps:

(1) in 200 ~ 250 g block graphite, puts the crusher in the crushing and 150 mesh sieve, graphite powder, graphite powder and put in 1 l beaker, and to add 600 ~ 700 ml beaker mass fraction is 85% sulfuric acid, stirring evenly mixed, and then to join in a beaker of 7 ~ 8 g potassium permanganate, stirring and heating heating to 70 ~ 70 degrees, 1 ~ 2 h reaction;

(2) after the reaction, then to join in a beaker mixture quality 15 ~ 20% mass fraction is 17% hydrogen peroxide solution, stirring evenly mixed, and put the beaker in 0 ~ 2 degrees ice water bath, freezing crystallization 50 to 55 min after the crystallization of mixture in the centrifuge in centrifugal separation, the control speed is 200 ~ 220 r/min, the centrifugal 40 ~ 45 min, stay after the separation, collection of centrifugal, will collect the centrifugal content on temperature is 60 ~ 70 degrees oven drying after 1 ~ 2 h, then put in ball mill ball mill and 170 mesh sieve, get nano graphite powder;

(3) in 200 ~ 250 g, metal tungsten to place it in the furnace and zhongtong into the calciner to calcine furnace volume two-thirds of oxygen, stay bubbled into complete, calcination, control the calcination temperature is 800 ~ 850 degrees, calcination, after 1 ~ 2 h using spray gun to the preparation of nano graphite powder injection to calcine furnace, control air injection rate is 0.20 ~ 0.25 kg/s.

(4) at the same time, access to the calcination furnace burning furnace, a third volume of hydrogen stay bubbled into complete, improve the calcination furnace temperature to 1200 ~ 1350 degrees, calcined reaction after 2 ~ 3 h, using liquid nitrogen to make it cool within 50 ~ 60 s to the 500 ~ 600 degrees, the heat preservation after 10 ~ 15 min, cool again to 100 ~ 250 degrees, heat preservation after 7 ~ 8 min, finally to 30 ~ 40 degrees, cooling heat preservation after 10 ~ 15 min, then put in mill grinding and 200 mesh sieve, can cast tungsten carbide powder preparation.

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