Temperature-Adaptive Self-Lubricating Alloys with Soft Silver and Tribo-Chemical Silver Vanadate

Self-adaptive conception provides a reference for design of high-temperature self-lubricating material. Herein, temperature-adaptive Ni3Al-based self-lubricating alloys were designed and fabricated based on soft lubricating silver and tribo-chemical silver vanadate, and their performance was investigated over a broad range of temperatures. Ni3Al-Ag-V alloys exhibit excellent self-lubricating properties and wear resistance over a wide temperature range, especially for the Ni3Al-20 wt.%Ag-5 wt.%V alloy with friction coefficients as low as 0.26 and 0.23 at room temperature and 900 °C, respectively, and wear rates as low as 5 × 10−6 mm3/Nm and 4 × 10−5 mm3/Nm in turn. It is proposed for a temperature-adaptive lubrication mechanism, such as tribo-chemistry of silver vanadate, tribo-transfer film, and the synergistic lubrication effect of soft metal Ag at low temperatures and silver vanadate at high temperatures.