The self-lubricating ceramic coatings that can control friction and wear have attracted researchers’widespread attention.However,the poor interfacial bonding between lubricants and ceramics and the deterioration of m...The self-lubricating ceramic coatings that can control friction and wear have attracted researchers’widespread attention.However,the poor interfacial bonding between lubricants and ceramics and the deterioration of mechanical properties due to a tribological design limit their practical applications.Here,a robust self-lubricating coating was fabricated by an in-situ synthesis of MoS_(2)/C within inherent defects of thermally sprayed yttria-stabilized zirconia(YSZ)coatings.The edge-pinning by noncoherent endows hybrid coatings with excellent interfacial strength,increasing their hardness(HV)and cohesive strength.Furthermore,owing to the formation of a well-covered robust lubricating film at a frictional interface,a coefficient of friction(COF)can be reduced by 79.6%to 0.15,and a specific wear rate(W)drops from 1.36×10^(−3) to 6.27×10^(−7) mm^(3)·N^(−1)·m^(−1).Combining outstanding mechanical properties and tribological performance,the hybrid coating exhibits great application potential in controlling friction and wear.Importantly,this strategy of introducing the target materials into the inherent defects of the raw materials to improve the relevant properties opens new avenues for the design and preparation of composite materials.展开更多
In order to reduce the friction coefficient of a pure nickel coating and extend the lifetime of metal parts under extreme friction conditions,a series of Ni-based WS2-composite solid lubrication coating containing dif...In order to reduce the friction coefficient of a pure nickel coating and extend the lifetime of metal parts under extreme friction conditions,a series of Ni-based WS2-composite solid lubrication coating containing different WS2 concentrations were prepared on a 45#mild carbon steel substrate by electroplating.The cyclic voltammetry method was used to investigate the electroplating regulation of the Ni-WS2 composite coatings.X-ray diffraction(XRD) and scanning electron microscopy(SEM) were used to analyze the microstructures and wear surfaces of the composite coatings,the tribological properties and wear mechanisms of the composite coatings with different WS2 concentrations.The results show that the addition of WS2 can promote the cathode polarization of the electroplating process,and the polarization degree goes up with the increase in WS2 concentrations.The friction coefficient of Ni-composite coatings significantly decreases by the addition of WS2 particles.The lowest friction coefficient at room temperature is obtained at a value around 0.01-0.03 from the coating deposited in the electrolyte solution with a 30g·L^-1 WS2 concentration.The friction coefficient of the Ni-WS2 composite coating remains in 0.01-0.03 with the increase in temperature from room temperature to 300℃.When the temperature goes up to 500℃,the friction coefficient manifests a continuous increase to 0.12,because WS2 is gradually oxidized into WO3 and therefore loses its lubrication ability.展开更多
基金support from the National Natural Science Foundation of China (51905212)Guangdong Key Laboratory of Modern Surface Engineering Technology (2020B1212060049)+2 种基金Science and Technology Project of Guangdong Academy (2021GDASYL-20210103062)Young Scientific and Technological Talents Promotion Project of Guangzhou Science and Technology Association (X20210201061)Foshan Taoyuan Institute of Advanced Manufacturing (TYKF202203003).
文摘The self-lubricating ceramic coatings that can control friction and wear have attracted researchers’widespread attention.However,the poor interfacial bonding between lubricants and ceramics and the deterioration of mechanical properties due to a tribological design limit their practical applications.Here,a robust self-lubricating coating was fabricated by an in-situ synthesis of MoS_(2)/C within inherent defects of thermally sprayed yttria-stabilized zirconia(YSZ)coatings.The edge-pinning by noncoherent endows hybrid coatings with excellent interfacial strength,increasing their hardness(HV)and cohesive strength.Furthermore,owing to the formation of a well-covered robust lubricating film at a frictional interface,a coefficient of friction(COF)can be reduced by 79.6%to 0.15,and a specific wear rate(W)drops from 1.36×10^(−3) to 6.27×10^(−7) mm^(3)·N^(−1)·m^(−1).Combining outstanding mechanical properties and tribological performance,the hybrid coating exhibits great application potential in controlling friction and wear.Importantly,this strategy of introducing the target materials into the inherent defects of the raw materials to improve the relevant properties opens new avenues for the design and preparation of composite materials.
基金financially supported by International Science and Technology Cooperation Program of China(No.2015DFR51090)the Supporting Program of Gansu Province(No.1604WKCA008)
文摘In order to reduce the friction coefficient of a pure nickel coating and extend the lifetime of metal parts under extreme friction conditions,a series of Ni-based WS2-composite solid lubrication coating containing different WS2 concentrations were prepared on a 45#mild carbon steel substrate by electroplating.The cyclic voltammetry method was used to investigate the electroplating regulation of the Ni-WS2 composite coatings.X-ray diffraction(XRD) and scanning electron microscopy(SEM) were used to analyze the microstructures and wear surfaces of the composite coatings,the tribological properties and wear mechanisms of the composite coatings with different WS2 concentrations.The results show that the addition of WS2 can promote the cathode polarization of the electroplating process,and the polarization degree goes up with the increase in WS2 concentrations.The friction coefficient of Ni-composite coatings significantly decreases by the addition of WS2 particles.The lowest friction coefficient at room temperature is obtained at a value around 0.01-0.03 from the coating deposited in the electrolyte solution with a 30g·L^-1 WS2 concentration.The friction coefficient of the Ni-WS2 composite coating remains in 0.01-0.03 with the increase in temperature from room temperature to 300℃.When the temperature goes up to 500℃,the friction coefficient manifests a continuous increase to 0.12,because WS2 is gradually oxidized into WO3 and therefore loses its lubrication ability.
