High Temperature Sliding Abrasive Wear Performance of HVOF-Sprayed Cr3C2-NiCr Coatings: Oxidation Induced Behavior and Mechanism

Abstract: Currently, HVOF-formed Cr3C2-NiCr coating is widely used due to its excellent resistance to thermal-induced wear degradation at temperatures up to 850 oC. Our previous research focused on comparing different feedstock materials to determine the optimal Cr3C2-NiCr coatings for sliding abrasive wear at room temperature. This ongoing study aims to investigate the sliding abrasive performance of these optimal coatings under oxidation-induced conditions. Experimental analysis involves characterizing the in-situ tribological behaviors of the coating at high temperatures and evaluating the wear performance of pre-oxidized coating specimens. The goal is to understand how oxidation and abrasion factors influence the sliding abrasive wear behavior of the coatings. Various test methods, such as pin-on-disk test, Taber wheel test, and disk rotating test, were used to characterize the abrasive wear behavior. Additionally, detailed studies on abrasive wear mechanisms were conducted through XRD, SEM morphologies, TGA, and surface profile analyses of the test samples. Special attention was given to the effect of TGO layers on the wear behavior, the impact of feedstock materials on coating microstructures, TGO growth, and abrasive tribological behavior to identify the optimal coating for enhanced sliding abrasive wear resistance at high temperatures.