High-temperature tribological performance of Ni-based coating on 316L stainless steel

In this paper, tribological results are presented for the sliding wear of APS and HVOF sprayed Ni-based coatings (NiCrBSiFeC) at 500 °C. Sliding wear under high-temperature conditions is encountered in various industrial applications such as power generation, nuclear power plants, turbines, hot forming, and aerospace. To mitigate wear and high-temperature oxidation, components are often coated using thermal spraying techniques. Ni-based coating powder was applied to 316L stainless steel under optimized spraying conditions using both APS and HVOF techniques. A dry sliding wear testing setup, consisting of a pin-on-disc tribometer with a heating chamber, was used according to ASTM G99 standards. A high-hardness Silicon-Nitride (Si3N4) ball served as the counter-material. The sliding wear rate and coefficient of friction were analyzed under the specified operating conditions. An improvement of up to 40% in wear resistance was observed with the HVOF-coated specimens compared to those sprayed using APS, indicating significantly lower wear rates with the HVOF technique. The wear tracks on the coatings were examined using scanning electron microscopy (SEM), providing insights into the wear mechanisms.