Production Methods Of Tungsten Carbide Powder

       

Today we will talk about production methods of tungsten
carbide powder. First, tungsten powder (average particle size 3 ~ 5) is
prepared by hydrogenation and reduction of tungsten trioxide WO3 μ m）。 Then, the average
particle size is 3 ~ 5 with tungsten powder and carbon black as raw materials μ
M of tungsten powder and carbon black in equal amount shall be dry mixed with a
ball mill, fully mixed, pressurized and formed, put into a graphite disc, and
then heated to 1400 ~ 1700 ℃ in a graphite resistance furnace or induction
furnace, preferably 1550 ~ 1650 ℃. In the hydrogen gas stream, W2C is initially
generated and continues to react at high temperature to generate tungsten
carbide. Or firstly, hexacarbonyl tungsten [w (CO) 6] is thermally decomposed
in 650 ~ 1000 ℃ and co atmosphere to obtain tungsten powder, and then reacts
with carbon monoxide at 1150 ℃ to obtain tungsten carbide. If the temperature
is higher than this temperature, W2C can be formed.

Then, Gas phase decomposition method. Tungsten
powder was prepared by thermal decomposition of hexacarbonyl tungsten w (CO) 6.
A method for preparing tungsten carbide by carburizing with carbon monoxide
gas. The characteristic of this method is that tungsten carbide can be easily
prepared at low temperature (1150 ℃) with a relatively simple reaction device
without the high temperature as method1.

 

Tungsten carbide powder is dark gray, has
metallic luster, and its hardness is similar to that of diamond. It is a good
conductor of electricity and heat. Melting point 2870 ℃, relative density
15.63, mainly used in the production of cemented carbide. Tungsten carbide is
insoluble in water, hydrochloric acid and sulfuric acid, and is easily soluble
in nitric acid hydrofluoric acid mixed acid. Pure tungsten carbide is fragile.
If a small amount of titanium, cobalt and other metals are added, the
brittleness can be reduced. As a steel cutting tool, tungsten carbide is often
added with titanium carbide, tantalum carbide or their mixture to improve its
explosion resistance. Tungsten carbide is chemically stable. Tungsten carbide
has insufficient high-temperature oxidation resistance. When the temperature
reaches 500 ℃ - 800 ℃, it is easy to oxidize and decompose into W2C and carbon
in air. To solve this problem, tungsten carbide particles can be pre protected
by using heat-resistant and oxidation-resistant metal as coating or bonding
phase. It can also form composite carbides with TAC, tic and other solid
solutions to improve the heat resistance and oxidation resistance of tungsten
carbide. Tungsten carbide is still stable when heated to 2850 degrees in Ar
atmosphere, and is not affected in high temperature nitrogen.

 

For more information about the 3D printing
powder, spraying coat powder, or WC based powder, you may search online
wococarbide. Wococarbide.com provides various products and technical questions
and answers.