固结磨料研磨垫孔隙结构对其加工性能的影响

Influence of pore distribution of fixed abrasive pad on its machining performance

为了解决铜在研磨过程中铜屑黏附减小了容屑空间,易导致研磨垫钝化问题,本文尝试在亲水性固结磨料研磨垫(FAP)内部添加硫酸镁晶体,利用硫酸镁晶体遇水溶解的特性,在研磨垫表面制造不同特征的孔隙。实验在FAP中添加粒径为8目、170目、500目的硫酸镁晶体制造了3种不同孔隙分布的研磨垫,研究了不同加工参数下FAP研磨铜片时的材料去除速率、摩擦系数、表面形貌及磨屑特征。结果表明,仅含170目硫酸镁的FAP与含8目和500目硫酸镁、质量分数分别为5%和10%的FAP在研磨过程中出现了不同程度的钝化,而FAP表现出良好的自修整性能,研磨过程摩擦系数较大且保持平稳;在研磨液流量为60ml/min时,其材料去除速率为4.46μm/min,表面粗糙度Ra为159nm。

Copper is easy to adhere to the surface of a tool during the process of grinding or lapping,which may decrease the space for chips and lead to the passsivation of a Fixed Abrasive Pad （FAP）.To resolve the problem,this paper adds the magnesium sulfate crystal with water dissolved characteristics into the hydrophilic FAP to prepare holes with different characteristics on the surface of the FAP.In this study,different sizes of magnesium sulfate （MgSO4） particles （8 mesh,170 mesh and 500 mesh respectively） were added to the FAP to prepare three different FAPs.Material removal rates,friction coefficients,surface topography,and chip characteristics were obtained when lapping copper using different FAPs on different machining pa-rameters.Results show that the FAP contained 170 # MgSO4 particles only and the one contained 8 # and 500 # MgSO4 particles with a mass fraction of 10％ and 5％,were glazing to some extents during the process of lapping.However,the FAP containing 8# and 500# MgSO4 particles with a mass fraction of 5％ and 10％shows a good self-conditioning performance and its friction coefficient during lapping is larger and stable.With lapping liquid flow rate at 60 ml/min,the material removal rate is 4.46μm/min and the surface roughness Ra is 159 nm.