Abstract:The mechanism of micro-structure and coating performance of tungsten coating were discussed.The influence of spraying parameters on the properties of plasma spraying tungsten coating includ the spraying power, spraying distance and pulerized gas delivery. The results indicate tungsten molten drop spread to form the pancake morphology or flower morphology owing to singel layer overlying, which is the columnar crystal microstructure. The particle molting state, the deposition velocity and the spraying environment determine the morphology of tungsten coating.And the pancake morphology with a thickness of about 10 μm and a diameter of about 50 μm is the better coating structure. Compared with atmospheric plasma spraying tungsten coating, vacuum plasma spraying tungsten coating has lower porosity,better heat transfer capability, better bonding strength and less oxygen content.Therefore, tungsten coating used as plasma facing material is feasible.