Elevated-temperature wear behaviors of NiMo/Mo2Ni3Si intermetallic “in situ” composites

Intermetallic composite has been expected to be one kind of high-performance wear material at elevated temperature due to its inherent high hardness and strong atomic bonds. This paper presents the wear behaviors under elevated temperature conditions of NiMo/Mo2Ni3Si intermetallic “in situ” composite. Metallographic observations were carried out with optical microscope and scanning electron microscope. Elevated-temperature wear tests were performed under pin-on-disc mode dry sliding conditions. Results shown that the relative wear resistant property of NiMo/Mo2Ni3Si alloys at 500 °C is over 7 times, and become higher at 550 °C compared with austenitic 1Cr18Ni9Ti stainless steel. The effect of temperature and applied load on elevated-temperature wear resistance of alloy was evaluated. The corresponding wear mechanism is also reported through examining the worn surface, subsurface, and wear debris of the NiMo/Mo2Ni3Si intermetallic alloys which is found to be soft abrasive wear.