Study on erosion wear resistance of HVOF-sprayed WC-12Co coatings based on Taguchi method
GUO Huafeng1*, ZHU Congcong2, ZHAO Enlan1,2, LI Longhai1, YU Ping1, LIU Lei1, YANG Haifeng2
1. School of Mechanical and Electronic Engineering, Xuzhou University of Techology, Xuzhou, Jiangsu 221018, China; 2. School of Mechatronic Engineering, China University of Mining and Technology, Xuzhou, Jiangsu 221116, China
Abstract：WC-12Co coating was prepared by high-velocity oxygen-fuel(HVOF)technology. SEM, EDS were used to characterize the micro-morphology, element distribution and chemical composition of the surface/cross section of the coating before and after erosion. The Taguchi Design of Experiments(DOE)techniques and the erosion tester were used to analyze the effects of erosion distance, impact angle and abrasive mass on the erosion rate of the coating, and the erosion mechanism of the coating was discussed. The results show that the microstructure of WC-12Co coating is uniform and there are a small amount of pores. The bonding mode between coating and substrate is mainly mechanical bonding. The range and variance analysis show that under the existing erosion conditions, the erosion distance has the most significant effect on the erosion rate of the coating, followed by the impact angle and the abrasive mass, and the erosion rate is the smallest at the impact angle of 30°, followed by 60°and 90°. Compared with high impact angle, WC-12Co coating has excellent resistance at low impact angle. The erosion mechanism of the coating at the impact angle of 30° is cutting and ploughing damage, accompanied by a small amount of brittle fracture and spalling, and brittle fracture and fatigue spalling caused by positive hammering at 90°. The depth of peeling pit at 90° is much greater than that of cutting and ploughing at 30°, and the damage is more serious.