Achieving exceptional ultra-high-speed rubbing resistance in NiAlTa/cBN composites through precise structural and compositional design

Abstract

Friction and wear cause about 23% of global energy consumption in terms of energy and material loss, so reducing and controlling wear is a relentless pursuit. Realizing wear resistance under extreme operating conditions (ultra-high speeds, ultra-high temperatures, and ultra-high strain rates) is the pursuit of material design. Here, a NiAlTa/cBN composite is developed for high-temperature turbine blade tips to achieve wear and impact resistance through precise material component and structure design. The composite exhibits the lowest incursion depth ratio reported to date. This excellent ultra-high-speed rubbing resistance stems from the high thermal-softening resistance of its intrinsic structure and the synergistic hardening induced by multiple deformation pathways (superdislocations, FCC→HCP phase transitions, faults, and deformation twins). The optimized design of the metal/ceramic interface and the tribo-induced tribo-layers with heterostructures also contribute to the excellent ultra-high-speed rubbing resistance. At high strain rates, the atomic order-to-disorder transition at the interface can effectively coordinate plastic deformation and dissipate impact strain energy.