AZ80A、ZK60A和ME20M镁合金干摩擦学性能研究  

Study on the Tribological Properties of AZ80A,ZK60A and ME20M Magnesium Alloys Under Dry-sliding Condition

作　　者：崔功军 师睿博 李赛 刘慧强 寇子明 CUI Gongjun;SHI Ruibo;LI Sai;LIU Huiqiang;KOU Ziming(College of Mechanical and Vehicle Engineering,Taiyuan University of Technology,Taiyuan 030024,China;National-local Joint Laboratory of Mining Fluid Control Engineering,Taiyuan 030024,China;Shanxi Research Center of Mining Fluid Control Engineering,Taiyuan 030024,China)

机构地区：[1]太原理工大学机械与运载工程学院,太原030024 [2]矿山流体控制国家地方联合工程实验室,太原030024 [3]山西省矿山流体控制工程技术研究中心,太原030024

出　　处：《材料导报》2021年第10期10103-10108,共6页Materials Reports

基　　金：国家自然科学基金(51775365);国家自然科学基金青年基金(51405329)。

摘　　要：镁合金被广泛应用于航空航天、汽车及军事等领域,但其摩擦学性能对零部件的服役寿命和可靠性具有重大影响。本研究采用往复式球-盘摩擦方式,通过与GCr15钢球配副,研究干摩擦条件下AZ80A、ZK60A和ME20M镁合金在不同滑动速度和载荷条件下的摩擦磨损行为。采用扫描电子显微镜和能谱仪分析镁合金的显微结构及磨损机理。结果表明:当滑动速度超过0.10 m/s时,随着速度的增加,合金的摩擦系数逐渐降低,而磨损率则先减小后增大,其原因在于摩擦热的作用导致摩擦表面形成了氧化物,同时材料表面软化,剪切力降低,使摩擦系数和磨损率不断减小;当滑动速度增加到0.20 m/s时,摩擦表面温度升高,金属软化导致磨损表面金属氧化物剥落,增大了合金的磨损率。随着载荷的增加,合金的摩擦系数和磨损率持续降低。干摩擦条件下镁合金的磨损机理逐渐由磨粒磨损和塑性变形转变为磨粒磨损、氧化磨损、粘着磨损和塑性变形。与ZK60A和ME20M相比,AZ80A镁合金表现出较好的摩擦学性能,这归因于合金的高硬度、β-Mg_(17)Al_(12)硬质相的支撑作用以及摩擦过程中形成的氧化物。Magnesium alloys were widely used in the aerospace,automotive and military fields,and the reliability and service life of moving parts of magnesium alloys depended on their tribological properties.In this paper,the tribological behavior of AZ80A,ZK60A and ME20M magne-sium alloys was tested by using a reciprocating ball-on-disk tribometer sliding against GCr15 steel ball under dry-sliding condition at different applied loads and sliding speeds.The wear mechanisms of magnesium alloys were analyzed by the scanning electron microscope and energy spectrometer at different loads and speeds.The results showed that the friction coefficients of alloys gradually decreased with the increase of sliding speed when the sliding speed exceeded 0.10 m/s.However,the wear rates decreased,and then increased.It was ascribed to the low shear force and formation of oxides on the worn surfaces due to the friction heat.When the sliding speed reached up to 0.20 m/s,the metal oxides peeled off from the surface in order to increase the wear rates of alloys because of the elevated temperature.The friction coefficients and wear rates of alloys increased as the applied loads increased.The wear mechanisms of magnesium alloys transferred from the abrasive wear and plastic deformation to the abrasive wear,oxidative wear,adhesive wear and plastic deformation under dry-sliding condition.The AZ80A alloy showed the good tribological properties as compared with ZK60A and ME20M alloys.It was ascribed to the high hardness,β-Mg_(17)Al_(12) hard phase and metal oxides on the contacting surfaces.

关 键 词：镁合金 干滑动 摩擦 磨损 

分 类 号：TH117.1[机械工程—机械设计及理论]