Ti6Al4V合金表面火焰喷焊W_xC涂层耐磨性分析

Research of Wear Resistance of Flam Spray-welding W_xC Coating on Ti6Al4V Alloy Substrate

摘要:

采用"一步法"火焰喷焊技术在Ti6Al4V合金表面制备出由Ni60过渡层和W_xC+Ni60强化层组成的喷焊层。喷焊层在氩气气氛中冷却,避免了涂层的氧化。过渡层与基体结合良好,没有孔洞等缺陷;强化层中碳化钨颗粒呈弥散分布,与过渡层界面处存在大量的孔洞。喷焊层硬度为12. 3 GPa,相比基材,硬度提高了近3倍,摩擦系数降低60%以上。喷焊层与GCr15和Si_3N_4对磨后,对磨副GCr15和Si_3N_4磨损严重,而喷焊层无明显磨损,表现出优异的耐磨性。

Abstract:

One-step flame spray-welding method was adopted to prepare a well-resistance coating containing W_xC + Ni60 reinforced layer and Ni60 transition layer on Ti6Al4V alloy. The spray-welding layer was cooled in argon atmosphere to avoid the coating oxidation. The results show that the transition layer of the coating bond well with the substrate without holes and other defects. The tungsten carbide particles in reinforced layer are distributed diffusely,and a large number of holes is found at the interface between the transition and strengthening layer. The hardness of the coating is 1. 23 GPa,which is more than 3 times higher than that of the Ti6Al4 V substrate. In comparison to Ti6Al4V substrate,the friction coefficient is reduced by more than 60%. The spray-welded coating shows excellent wear resistance with no obvious wear after wear test,but the against GCr15 and Si_3N_4 ball are badly worn.