砂轮约束磨粒喷射加工表面的分形及摩擦特性研究  

The Fractal Dimension and Tribological Characteristic Investigation of Finishing Surfaces for Abrasive Jet Finishing Restricted by Grinding Wheel

作　　者：刘枫[1] 巩亚东[1] 单玉桥[2] 蔡光起[1] 

机构地区：[1]东北大学机械工程与自动化学院,辽宁沈阳110004 [2]东北大学材料与冶金学院,辽宁沈阳110004

出　　处：《摩擦学学报》2009年第4期379-384,共6页Tribology

基　　金：国家自然科学基金资助项目(50475052);教育部博士点专项基金资助项目(20040145001)

摘　　要：对砂轮约束磨粒喷射精密光整加工(Abrasive Jet Precision Finishing,AJF)表面进行分形维数和摩擦磨损特性研究.试验在MB1332A外圆磨床上完成,加工式样为Ra为0.6μm左右的45#钢.加工表面形貌和微观几何参数用MICROMESVRE2表面轮廓仪测量;应用分形维数和功率谱密度函数评价磨削加工和光整加工表面的微观形貌特征;利用MG-2000型销盘式高速高温摩擦磨损试验机研究表面形貌和分形维数对摩擦系数和磨损性能的影响.试验结果表明:磨粒喷射精密光整加工使工件表面高度特性参数大幅度降低,轮廓波动平均间距减小,波纹细密性提高.随着加工循环的增加,Ra值由0.6μm下降到0.2μm左右.光整加工表面摩擦系数和磨损量与磨削加工表面相比明显降低,摩擦磨损试验结果和分形维数变化相吻合.The fraetal dimension and tribological characteristic of abrasive jet finishing （AJF） surface were investigated. Experiments were performed on a cylindrical grinder MB1332A with a 45# steel workpiece as specimen with a surface roughness Ra of 0.6 μm. The micromorpbology and microcosmic geometry parameters of machined surface were measured with Micromesver2 profilometer. According to the metrical results, the surface topographies before and after finishing were evaluated with fractal dimension and power spectral density （PSD）. Effects of surface morphology and fractal dimension on the tribological characteristics of finished surface were also investigated with a MG- 2000 pinon -disk wear tester . The results showed that longitudinal geometry parameter values of finished surface were reduced compared with that of the ground surface. The mean ripple distance decreased while ripple and peak densities increased. The R,, gradually decreased from an initial value of about 0.6 μm to about 0. 2μm with the increase of machining cycles. The coefficient of fiiction and wear of finishied surface were much lower than that of ground surface. The experimental results of tribological characteristics were in good agreement with the variation of fractal dimension.

关 键 词：磨粒喷射精密光整加工(AJF) 表面形貌 分形维数 摩擦磨损 

分 类 号：TG580.699[金属学及工艺—金属切削加工及机床]