HVOF制备的Ni60/WC-10Co4Cr涂层组织和滑动磨损性能研究

为了降低超音速火焰(HVOF)喷涂金属陶瓷涂层的材料和加工成本,使其在更大范围内替代会给环境带来严重污染的电镀硬铬(EHC)涂层,本文将不同比例的Ni60与WC-10Co4Cr相混合,并采用HVOF喷涂工艺分别制备了5种金属陶瓷复合涂层.研究了这些涂层的显微组织、基本性能和滑动磨损性能,并将其与EHC涂层进行对比.结果表明:所有HVOF喷涂工艺制备的Ni60/WC-10Co4Cr涂层都很致密(孔隙率小于1%),随着WC-10Co4Cr比例的增加,Ni60/WC-10Co4Cr涂层的硬度从688.3 HV0.3增加到1 203.4HV0.3,磨损率由2.75×10~(-5) mm~3/N·m降低到7.29×10~(-7) mm~3/N·m.并且,所有HVOF喷涂工艺制备的涂层和与其配对的摩擦副的磨损率以及磨擦系数均低于EHC涂层,表现出良好的抗滑动磨损性能.

Study on Microstructure and Sliding Wear Performance of Ni60/WC-10Co4Cr Coatings Prepared by HVOF Process

In order to decrease the material and manufactural cost of the HVOF sprayed cermet coating, to replace the EHC in wider fields, five cermet composite coatings were deposited by HVOF process using the blended Ni60 and WC-10Co4Cr powders with different ratios. Microstructure, properties and sliding wear performance of the Ni60/WC-10Co4Cr coatings as well as electrolytic hard chrome (EHC) coating were investigated. The results showed that all the HVOF sprayed coatings were compact (porosities were less than 1%), their hardness increased from 688.3HV0.3 to 1203.4 HV0.3 and the wear rate decreased from 2.75×10-5 mm3/N·m to 7.29×10-7 mm3/N·m with increasing the WC-10Co4Cr ratio. The wear rates of the HVOF sprayed coatings and their counterparts as well as their frictional coefficient were lower in comparison to the EHC coating, which exhibited excellent sliding wear performance.