增强相对铝基复合材料超精密加工表面的影响  

Effect of Reinforcements on Ultraprecision Surface of SiC Reinforced Aluminum Matrix Composites

作　　者：王大镇[1] 冯培锋[1] 游玲[1] 李波[1] 刘华明[2] 

机构地区：[1]集美大学机械工程学院,厦门361021 [2]哈尔滨工业大学机电工程学院,哈尔滨150001

出　　处：《纳米技术与精密工程》2010年第5期452-459,共8页Nanotechnology and Precision Engineering

基　　金：福建省自然基金计划资助项目(E0640012)

摘　　要：采用聚晶金刚石（PCD）刀具对SiC增强铝基复合材料进行超精密车削加工试验,基于原子力显微镜（AFM）、扫描电子显微镜（SEM）和Talysurf-6型轮廓仪对加工表面进行检测和分析.结果表明,S iC增强相的切削变形机理对超精密级加工表面的影响重大（粗糙度Ra为0.025μm）.若增强相在解理面直接被切削刀具切断,则SiC增强相附近区域的表面粗糙度值范围为6~10 nm,故产生超精密级加工表面的可能性大;若增强相以拔出或压入的机理进行切削变形,则不易获得超精密级加工表面.较高的切削速度、较小的进给量、较小的刀具钝圆半径和较大的PCD刀具晶粒度都有助于获得超精密级的加工表面,而背吃刀量对其影响很小.SiC增强相的体积分数和类型也是影响超精密级表面质量的重要因素,增强相体积分数越高,表面质量越差,晶须增强铝基复合材料较颗粒增强铝基复合材料可获得更好的表面质量.Ultraprecision turning tests for SiC reinforced aluminum matrix composites were performed using polycrystalline diamond（PCD） tools and the quality of machined surfaces was examined and analyzed with atomic force microscope（AFM）,scanning electron microscope（SEM） and Talysurf-6 roughometer.Experimental results indicate that the deformation mechanism of SiC reinforcements has a significant impact on the quality（roughness Ra=0.025 μm） of the machined surfaces of SiC reinforced aluminum matrix composites.Ultraprecision machined surfaces are easier to produce if reinforcements are directly cut off on the cleavage plane and the roughness of the machined surfaces is between 6 nm and 10 nm while it is difficult to obtain ultraprecision machined surfaces if the deformation mechanism of the reinforcements is pullout or pressing in.Higher cutting speed,smaller feed rate,smaller tool nose radius and larger crystal granularity of PCD tool contribute to obtaining ultraprecision machined surfaces yet the depth of cut has little effect.Volume fraction and type of SiC reinforcements are also important factors that affect the quality of the machined surfaces.Higher volume fractions will lead to poorer surface quality.Better surface quality can be achieved with SiC whiskers reinforced aluminum matrix composites rather than with SiC particles reinforced aluminum matrix composites.

关 键 词：铝基复合材料 超精密加工 SiC增强相 表面粗糙度 

分 类 号：TG51[金属学及工艺—金属切削加工及机床]