Quantitative Research On Self-conditioning Performance Of Hydrophilic Fixed Abrasive Lapping Pad

With the continuous development of microelectronics,optoelectronics,sensor technology and materials technology,various kinds of optical materials have been widely used,but also it has proposed higher requirements on ultra-smooth damage-free processing of the optical materials.The traditional fixed abrasive lapping and polishing technology due to the hardness of the binder,processing optical materials easy to produce large damage layer,seriously affecting the optical material processing efficiency and performance.Therefore,hydrophilic fixed abrasive lapping and polishing technology is proposed.Self-conditioning is one of the most important properties of hydrophilic fixed abrasive lapping and polishing pad(FAP),exerts great impact on processing efficiency and surface quality of processed workpiece.In this paper,the quantitative relationship between the self-conditioning performance of hydrophilic FAP and the main influencing factors was established by the combination of theoretical analysis and experimental exploration.The main completed work as follows:(1)The realization approach of hydrophilic FAP self-conditioning performance was explored.Self-conditioning process model of hydrophilic FAP was established.The influencing factors of self-conditioning property of hydrophilic FAP were preliminarily determined.The effect of factors levels on the self-conditioning performance of hydrophilic FAP was investigated by single-factor experiment.The research showed that hydrophilic FAP self-conditioning performance improved with the increase of material hard brittleness,grinding pressure and diamond particle size.With the increase of copper content in FAP,the content of triethanolamine in the slurry,and porosity factor,the self-conditioning performance of hydrophilic FAP increased first and then decreased.(2)The material removal rate variation of work-piece was chosen as the index to assess the self-conditioning performance of hydrophilic FAP.The quantitative relationship between the self-conditioning performance of hydrophilic FAP and factors,which are the material properties(critical depth of brittle-plastic transition),grinding pressure,diamond particle size,porosity factor,copper content in FAP,were explored with the regression orthogonal experiments method.The regression equation of the self-conditioning performance of hydrophilic FAP was established.The effect of wear debris on the self-conditioning performance of hydrophilic FAP was investigated by statistical analysis of the shape and size of the wear debris in lapping process.The results showed that the significant factors affecting on the self-conditioning performance of hydrophilic FAP are material properties,porosity factor,interaction between porosity factor and grinding pressure.As the grinding process continues,the wear debris size decreases,which leads to the hydrophilic FAP self-conditioning performance decreases.(3)The effects of material properties,grinding pressure,porosity factor and weakening rate of matrix strength at various levels on the self-conditioning performance of hydrophilic FAP were investigated by the orthogonal experiment.At the same time,the relationship between the self-conditioning performance of hydrophilic FAP and the surface quality of processed work-piece was correlated.The results showed that the hydrophilic FAP self-conditioning process was easy to realize with the increase of workpiece material brittleness and grinding pressure.The surface quality of processed work-piece is superior when the hydrophilic FAP has better self-conditioning ability.