超音速火焰喷涂铝青铜涂层微动磨损行为

Fretting Wear Behavior of Aluminum Bronze Coating by HVOF

目的改善铝合金的抗微动磨损性能。方法采用超音速火焰喷涂技术在ZL114A铝合金表面制备铝青铜涂层,在不同温度(25、200、300℃)下对有、无涂层的ZL114A铝合金样品进行微动磨损测试,通过对涂层性能和磨痕形貌进行表征分析,探索铝青铜涂层的抗磨损性能。结果铝青铜涂层均匀致密,与铝合金基体结合良好,显微硬度为279HV0.3,结合强度为74 MPa。不同温度(25、200、300℃)下,涂覆铝青铜涂层样品的平均微动摩擦系数分别为0.898、0.886、0.744,磨损率分别为10.249×10^(-7)、0.035×10^(-7)、0.207×10^(-7) m^(3)/(N·m),相比基体的平均微动摩擦系数和磨损率,3种温度下分别下降了34.5%、42.9%和58.9%。对磨痕的形貌和三维轮廓的分析表明,在25、200、300℃下,铝青铜涂层的磨损机制不相同,25℃下为磨粒磨损和剥层,200℃下为磨粒磨损、剥层、氧化磨损和粘着磨损,300℃下为塑性变形、氧化磨损和粘着磨损。结论制备的铝青铜涂层改善了基体的抗微动磨损性能。

In order to improve the fretting wear resistance of aluminum alloy,aluminum bronze coating was prepared on the surface of aluminum alloy by HVOF.The fretting wear tests of ZL114A aluminum alloy with and without coating were carried out at different temperatures(25,200,300℃).The coating properties and wear morphology were characterized and analyzed to explore the anti-wear performance of aluminum bronze coating.The uniform and compact aluminum bronze coating had a good combination with the aluminum alloy substrate and its microhardness was 279HV0.3 and bonding strength was 74 MPa.At 25,200 and 300℃,the average fretting friction coefficient of aluminum bronze coating was 0.898,0.886 and 0.74 respectively.The wear rate of substrate and aluminum bronze coated aluminum alloy was 10.249×10^(-7),0.035×10^(-7) and 0.207×10^(-7) m^(3)/(N·m).Compared with the aluminum alloy substrate,the average fretting friction coefficient of aluminum bronze coated aluminum alloy at 25,200 and 300℃decreased by 34.5%,42.9%and 58.9%respectively.Through the observation and analysis for the morphology and the three-dimensional profile of the wear scars,it is found that the wear mechanism of the aluminum bronze coating was different at 25,200 and 300℃.The wear mechanism of the aluminum bronze coating was the abrasive and peeling wear at room temperature.The abrasive wear,peeling,oxidative and adhesive wear occurred at 200℃.Plastic deformation,oxidative wear and adhesive wear occurred at 300℃.Therefore,the prepared al-bronze coating can improve the fretting wear resistance of the substrate.