Study of sliding wear and erosion wear of HVOF sprayed alloy 718 and Al₂O₃ composite coating on GCI substrate

In this study superalloy Alloy-718 has been selected as a coatings with Al₂O₃ as reinforcement, and four samples were used in accordance with the addition of Al₂O₃ to Alloy718 from 10% to 30% and wear performance and Alloy-718/Al₂O₃ composite coatings’ erosion behaviour has been studied to study the mechanical and micro-structural characteristics of super alloys combined with ceramics in the form of composite coatings. GCI has been selected as a substrate. Furthermore, the HVOF thermal spray technique has been selected for the present work as it offers the smoothest, hardest, lowest porosity and most homogenous microstructure coatings that are well bound. On a high-temperature pin-on-disc tribometer with unidirectional dry sliding, tribological studies have been conducted. Testing is conducted in accordance with ASTM G99-04 standard. At room temperature, 400°C, and 800°C, the tests were conducted with two distinct load values of 25 and 50 N, a speed of 1 ms1, and a sliding distance of 2000 m and it is found that the Abrasive wear co-efficient was calculated by using Archard’s Wear Relation and found that Alloy-718+30%Al₂O₃ 1.2X 10E⁻⁵ which is lower than other composite coated samples. Erosive wear rate is 1.9X10⁻⁴ and 1.8X10⁻⁴ at 30degrees and 60 degrees Eroded angles also less when compared to other coated samples.