重载条件下缸套磨损表面的分形特征研究

Research of Fractal Features of Cylinder Liner Wear Surface Over Loaded Conditions

为了分析负载和润滑油对缸套表面形貌的影响,采用布朗分形维数和多重分形谱定量表征不同工况下表面形貌分形特征及其高度的均一性。各工况条件下缸套表面平整程度由好到差依次为20 MPa稳定实验,20 MPa贫油实验(未拉缸),40 MPa稳定实验,20 MPa贫油实验(拉缸),未磨原试样。缸套表面高度均一性由好到差依次为20 MPa稳定实验,20 MPa贫油实验(未拉缸),40 MPa稳定实验,20 MPa贫油实验(拉缸),未磨原试样。分析结果表明,负载小时润滑充分可减小表面的磨损;增大负载时由于进入工作表面的润滑油减少,表面磨损加剧。

In order to analyze the influences of heavy load and lubricating oil on cylinder liner＇s surface topography, Brown＇s fractal dimension and multi-fractal spectrum were used to quantitatively characterize the fractal features and height homogeneity of its surface topography in different working conditions. In different conditions the leveling degrees of cylin- der liner＇s surface were in order from good to bad： in sufficient lubrication and stable working in 20 MPa, in deficient lu- brication and unstable working in 20 MPa （no cylinder scoring） , in sufficient lubrication and stable working in 40 MPa, in deficient lubrication and unstable working in 20 MPa （ cylinder scoring） , in original state before experiments. In differ- ent conditions the height homogeneity of its surface topography were in order from good to bad ： in sufficient lubrication and stable working in 20 MPa, in deficient lubrication and unstable working in 20 MPa （no cylinder scoring） , in sufficient lu- brication and stable working in 40 MPa, in deficient lubrication and unstable working in 20 MPa （cylinder scoring） , in original state before experiments. The result of the study dictates that the surface wear of cylinder liner is reduced at low load and sufficient lubrication condition, while the surface wear is increased at heavy load due to the decrease of lubrica- ting oil into the work surface.