Transitions in microabrasion mechanisms for WC - Co (HVOF) coated steel

In this work, the microabrasion of an HVOF (high-velocity oxy fuel) tungsten carbide (WC) - Co-based composite coating was investigated and compared with the performance of the substrate material, 316 stainless steel. The effects of sliding distance and applied load were investigated for both materials. Optical, scanning electron, and atomic force microscopy were used to characterize the surfaces following microabrasion. The results showed that the microabrasion rate peaked at intermediate loads for the materials. The critical load at which the peak was observed varied with sliding distance. There was a change in the performance of the coated versus the uncoated material, with the coating out-performing the substrate material at shorter sliding distances but with the reverse pattern occurring at longer sliding distances. The results were interpreted in terms of changes of microabrasion mechanisms as a function of increasing load and sliding distance. Microabrasion mechanisms were discussed based on the transition between wear volume as a function of load and sliding distance.