WC-M coating to improve resistance of hydraulic turbines to cavitation erosion and abrasion

摘要

WC-M hard-faced ceramic coating was made on the substrate of steel by means of high velocity oxygen-fuel flame (HVOF) thermal spraying. The resistance of this coating to cavitation erosion and abrasion (CEA) is a-bout 2. 5 times higher than that of 18 -8 stainless steel, and is about 1. 5 times higher than that of Stellite alloy (Co-CrWC) made in America. When this coating were applied to the hydraulic power stations with more silt content in the flow water, which reaches 50 kg/m~3, the resistance of above-mentioned coating to CEA was about 2 times to that of NiCr alloy coating, and is about 4 - 5 times to that of OCr13Ni4Mo stainless steel. In addition, the micro-hardness, microstructures and electron probe analyzing of the WC-M coating are all discussed.