There are many types of tungsten carbide coatings, and the hardness of coatings of different grades and compositions are different.
There is also the most important thing is the spraying process, different processes will also lead to different hardness of the coating.
Tungsten carbide coating hardness after spraying and the thickness of the coating does not have a large correlation, but only with it in the high temperature zone back to stay for a long time has a direct to the system.
Tungsten carbide coating hardness is generally more than HV1200.
For example: coating material chromium nitride (CrN) titanium nitride (TiN) titanium carbon nitride (TiCN) aluminum titanium nitride + tungsten carbide carbon film hardness were: HV1700/2200/3000/3000.
Tungsten metal and carbon as raw materials, the average particle size of 3 ~ 5μm of tungsten powder and an equal amount of carbon black with a ball mill dry mixing, mixing, pressure molding into graphite graphite. The tungsten powder and carbon black are dry-mixed in a ball mill with an equal amount of tungsten powder and carbon black, fully mixed, pressurized and shaped into a graphite disk, and then heated to 1400-1700°C in a graphite resistance furnace or induction furnace, preferably controlled at 1550-1650°C. In a stream of hydrogen, W?C is initially produced, and the reaction continues at high temperature to produce WC.
Expanded Information: The hardness of the coating is usually different due to the different spraying methods and conditions. This is because the hardness of the coating is determined by the size and structure of the coating particles, the number and size of the pores, and the amount of oxides and other compounds in the coating. And the spraying method or spraying conditions of the different factors often cause the above differences, resulting in different coating hardness, in general, the composition of the coating particles of the hardness itself than the hardness of the original coating material, which helps to enhance the coating and amplitude of the loss of performance, the micro-hardness of the spraying wire material and the wire material with which the air-sprayed layer of the micro-hardness of the particles of the comparison. The total carbon of WC used for alloys with different ranges of use, different cobalt contents and different grain sizes can be adjusted slightly. Low cobalt alloys can choose high total carbon tungsten carbide, high cobalt alloys can choose low total carbon tungsten carbide. In short, the specific needs of cemented carbide use different requirements for tungsten carbide particle size is also different. Reference: