Pan Jingjie, Liu Chang, Gao Xinxin, Zhang Kan, Zheng Weitao, Chen Changfeng
State Key Laboratory of Superhard Materials, Department of Materials Science and Key Laboratory of Automobile Materials, MOE, Jilin University, Changchun 130012, China.
College of Physics, Jilin University, Changchun 130012, China.
ACS Appl Mater Interfaces. 2021 Dec 15;13(49):59352-59363. doi: 10.1021/acsami.1c20034. Epub 2021 Dec 2.
Proper lubrication is essential to the reliable and efficient operation of mechanical systems ranging from the industrial to the nanoscale. Self-lubricating materials that can self-generate and sustain concurrent ultralow friction and ultralow wear in harsh environments open up a unique realm that is unattainable by traditional external lubrication mechanisms, but developing such extraordinary materials has been a long-standing grand challenge. Here, we devise an unconventional strategy to construct a dual-phase nanocomposite (DPNC) that comprises a wear-resistant phase (TiB) and an internal lubricant source (MoSB). Tribological tests demonstrate simultaneous ultralow friction coefficient (∼0.03) and ultralow wear rate (∼10 mm·N·m) of the synthesized DPNC specimen in ambient environments; these superb properties remain intact after the specimen has been annealed at 400 °C in air. First-principles energetic and stress-strain calculations elucidate atomistic mechanisms underpinning DPNC TiB/MoSB as an ultimate self-lubricating material. This accomplishment solves the classic lubricity-durability tradeoff dilemma, enabling advances to meet the most challenging lubrication needs.
适当的润滑对于从工业到纳米尺度的机械系统的可靠高效运行至关重要。能够在恶劣环境中自我产生并维持同时存在的超低摩擦和超低磨损的自润滑材料开辟了一个传统外部润滑机制无法企及的独特领域，但开发此类非凡材料一直是一项长期存在的重大挑战。在此，我们设计了一种非传统策略来构建一种双相纳米复合材料（DPNC），它由一个耐磨相（TiB）和一个内部润滑剂源（MoSB）组成。摩擦学测试表明，在环境条件下，合成的DPNC试样具有同时的超低摩擦系数（约0.03）和超低磨损率（约10 mm·N·m）；在空气中400°C退火后，这些优异性能依然保持完好。第一性原理能量和应力应变计算阐明了DPNC TiB/MoSB作为一种终极自润滑材料的原子机制。这一成果解决了经典的润滑性 - 耐久性权衡困境，推动了满足最具挑战性润滑需求的进展。
