Tungsten carbide powder spraying and its usage

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Tungsten carbide powder is a kind of hexagonal system crystal dark grey powder. Due to its high hardness, good wear resistance and stable chemical property, it is often used on spraying technology to improve the usability of finished products.

Tungsten carbide powder spraying is conducted by using the tungsten carbide powder that has the particle size of 50-80μm as raw materials and applying the spraying equipment at less than 1300 degrees Celsius. In the spraying process, the oxygen and fuel are sprayed into the combustor with high speed and high pressure, in which 2727 degrees Celsius of heat and 1500m/s high speed inflation airflow will be generated after burning, afterwards, the sprayed tungsten powder is sent into this kind of airflow and will be heated and sprayed on the combustor with high speed by using the method in which the powder is heated but not completely melted, thus the high quality tungsten carbide powder coating can be obtained.

This kind of high quality tungsten carbide powder coating, which has the HRC hardness of 68-75, is even and compact, besides, it is the best coating in resisting medium and low temperature abrasion and can be used in abrasion resistance, hard-surface, jogging and particle size erosion wear operational environment, for example, it can be used in the agitating vane in the plastic machinery, the screw conveyor and so on.

tungsten carbide powder spraying

The usage of tungsten carbide spraying

Tungsten carbide powder has high hardness and good wear resistance, especially the coating that made by tungsten carbide powder spraying is extremely even, hard and compact, which has a very wide application range. Below is the introduction to one of the applications of tungsten carbide powder spraying: tungsten carbide powder spraying piston rod.

Piston rod is one of the key components that have effect on transmitting power in the reciprocating compressor. It can work under high temperature, high pressure, tensile load and compressive load. As piston rod is often in the state of cyclic reciprocating motion, it not only has to bear the alternating stress caused by tension and compression in the motion process, but also has to bear the inertial force and friction generated by other components. Therefore, under the long term work, the piston rod is easy to wear.

In order to improve the corrosion resistance and wear resistance of compressor piston rod, the piston rod working surface can be coated by using tungsten carbide powder spraying so as to improve the quality of piston rod. The plasma spraying technology can be used in the spraying process, in which the high temperature ion gas that has more than 1000 degrees Celsius formed by ionizing gas that is sent into the plasma spraying gun via high frequency ignition will eject from the anode nozzle, afterwards, the powder is sent into the flame via gas carrier pipe, where it will melt and speed up and eventually spray on the surface of workpiece. This kind of process has high flame temperature, fast speed and controllable atmosphere, with which the sprayed piston rod will improve its surface corrosion resistance and wear resistance as well as extend its service life, therefore, it is deserved to be promoted.