Tribological Properties of Nickel-Based Superalloys GH4141 and K465 in a Wide Temperature Range

In this study, two typical nickel-based superalloys, GH4141 and K465, were selected to investigate their tribological properties from room temperature to 900 °C, and the friction and wear mechanisms of the two alloys at different temperatures were revealed. The results show that the average friction coefficient of GH4141 alloy exhibits a decreasing trend with increasing temperature, while that of K465 alloy first increases, then decreases, and finally increases again. At high temperatures of 800 °C and 900 °C, the average friction coefficients of both alloys drop below 0.3, demonstrating excellent high-temperature self-lubricating characteristics. The wear rates of both alloys gradually decrease with increasing temperature. From room temperature to 400 °C, K465 alloy exhibits a lower wear rate than GH4141 alloy, whereas from 600 °C to 900 °C, GH4141 alloy shows a lower wear rate, indicating its superior high-temperature wear resistance compared to K465 alloy. The wear mechanisms of both alloys in the moderate temperature range (room temperature to 400 °C) are primarily abrasive wear. As the temperature increases, an oxide glaze layer composed of various oxides forms on the worn surfaces of both alloys. The presence of this oxide glaze layer contributes to the improved friction reduction and wear resistance of the two alloys at elevated temperatures.