Tribological behavior and mechanism of Mo2Ti2C3/polyimide composite films under dry friction condition

Abstract

AbstractPolyimide (PI) has good mechanical properties and thermal stability, while high coefficient (COF) and wear rate limit its wide application. In order to endow PI with better friction and wear resistance, Mo2Ti2C3 MXene was used as solid lubricant to prepare Mo2Ti2C3/PI nanocomposites with different content of Mo2Ti2C3. The effect of the amount of Mo2Ti2C3 on the tribological behavior of PI was explored and the tribological mechanism was also analyzed Tribological tests showed that at 1.2 wt% of Mo2Ti2C3 addition, the composite material demonstrated superior friction and wear resistance, exhibiting a 19.9% decrease in the COF and a 79.7% decrease in the wear rate compared to single PI due to the good self‐lubricating properties of Mo2Ti2C3 MXene. Moreover, Mo2Ti2C3 can also effectively assist PI to form sleek transfer films without interruption or gaps on the steel balls, resulting in a reduced friction COF and wear rate of the material. This work demonstrates that Mo2Ti2C3 MXene is an aussichtsreich additive for polymers to improve the tribological properties and broadens the applications of Mo2Ti2C3/PI composites in friction material area.Highlights Mo2Ti2C3 significantly improves the tribological performance of polyimide. The thermal properties of Mo2Ti2C3/polyimide are enhanced by the introduction of Mo2Ti2C3. The minimum coefficient of Mo2Ti2C3/PI composites was only 0.246 at the 1.2 wt% content of Mo2Ti2C3. The wear rate of Mo2Ti2C3/PI composites was decreased by 79.7% at the 1.2 wt% addition of Mo2Ti2C3. Mo2Ti2C3 promotes the establishment of tribo‐film to protect the Mo2Ti2C3/PI composites from friction.