Composite Design and Friction-Wear Characteristics of High-Efficiency Transmission Gear Materials

Abstract

To meet the high-speed and heavy-load service requirements of high-efficiency transmission gears, Fe-2Ni iron-based powder metallurgy was used as the matrix, and a composite system reinforced by TiC hard phase and MoS2 solid lubricant was designed. The gear composites were prepared by hot pressing sintering. The effects of reinforcement ratio and sintering parameters on microstructure and mechanical properties were studied, and the friction and wear behaviors under different loads, sliding speeds and lubrication conditions were investigated. The results show that the optimal sintering process is 1150 ◦C, 60 min and 30 MPa, with a relative density of 98.6% and microhardness of HV 620. The composite with 10 wt% TiC and 3 wt% MoS2 exhibits the best comprehensive performance, with a friction coefficient as low as 0.08 and a wear rate reduced by 62% compared with the matrix. The wear mechanism transforms from abrasive wear to oxidative wear and slight delamination wear. The composite presents excellent friction reduction and wear resistance, which can provide a quantitative reference for the design of high-performance transmission gears.