In-situ liquid lubrication with bearing effect on a semi-out-of-plane ordered ternary (TiVCr)₃AlC₂ MAX at 800 ºC

Ternary (TiVCr)₃AlC₂ with a semi-out-of-plane chemical ordering is synthesized, and its temperature-dependent wear behavior is assessed at the temperature from 25 to 800 ºC. In the ternary MAX, V forms a solid solution with both Ti and Cr, which keeps the out-of-plane chemical ordering of Cr while breaking the ordering of Ti. By coupling with Si₃N₄, a reduction of mean wear rate is detected along with increasing temperatures starting at 200 ºC, which is relied on the states of the oxide glaze. Particularly, a synergism of in-situ liquid lubrication from molten oxides and a “bearing effect” provided by refractory oxide particles are observed at 800 ºC, which contributes to a low coefficient of friction (COF) of 0.25 and a low mean wear rate of 6.60 × 10⁻⁶ mm³ N⁻¹ m⁻¹.