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In this paper, the dry-sliding tests of Ti 3 AlC 2 /SiC tribopairs were conducted from 25 °C to 1000 °C in both air and argon atmospheres for confirming the roles of tribo-oxidation and laminate structure of Ti 3 AlC 2 . The characteristics of the worn surfaces of the Ti 3 AlC 2 were contrastively examined and the corresponding tribological mechanisms were discussed. Ti 3 AlC 2 showed distinctive tribological behaviors and mechanisms in the two atmospheres. Here, the tribo-oxidation film played a very vital role for the tribology of Ti 3 AlC 2 . In air, Ti 3 AlC 2 showed moderate wear at 25–400 °C and Ti 3 O 5 was the major phase of the tribofilms. At 600–1000 °C, the wear-resistant tribo-oxidation films, consisting of TiO 2 and Al 2 O 3 , were believed to be responsible for the negligible wear. In argon, Ti 3 AlC 2 exhibited heavy wear in the whole temperature range. Abrasive and adhesive wear caused the poor tribological performances at 800 °C and below. At 1000 °C, Ti 3 AlC 2 displayed plastic flowing and large furrows under the shear stress. [ABSTRACT FROM AUTHOR]

The mechanical and tribological properties of the Fe–15.88Al–5.46Cr (wt.%) based composites reinforced with 15, 25, 35 wt.% novel W 0.5 Al 0.5 C 0.5 particulates (referred to FA15, FA25 and FA35), produced by hot-press sintering, were evaluated. The hardness of the composites increased with the W 0.5 Al 0.5 C 0.5 content but the bending strength firstly decreased and then increased. The wear resistance of the composites was dramatically superior to Fe–15.88Al–5.46Cr alloy (FA0) without mass density gain. Interestingly, the wear resistance increased with W 0.5 Al 0.5 C 0.5 concentration from 15 to 25 wt.%, but then slightly declined when W 0.5 Al 0.5 C 0.5 content was up to 35 wt.%. It is also surprised that FA25 displayed the lowest friction coefficient, while that of other composites was much higher than Fe–15.88Al–5.46Cr alloy. These abnormal mechanical and tribological behaviors would be associated with the microstructure of the composites and the composition of the worn surfaces. The wear mechanism of the composites was abrasion and oxidation wear. [ABSTRACT FROM AUTHOR]