Abrasives Retaining Performance Of Fixed Abrasive Pad

Considering adhesion between abrasives and bonder has an important influence on machiningperformance of fixed abrasives pad(FAP). In this paper, the effects of material characteristics andabrasive surface modification on machining performance and abrasive retaining performance of FAPwere analyzed. In addition, image processing system for distinguishing the abrasives on the surface ofFAP was designed. The main work and results are as follow:1. Digital image identification system of FAP was designed, which contained hard system and softsystem. In the hard system, the numbers of incomplete diamond on the FAP and uncertain detectingresults were solved by increasing the magnification of microscope and normalizing camera siterespectively. In the soft system, three methods of diamond image identification (RGB identification,threshold value and edge detection method)were analyzed. The methods of RGB identification andthreshold value have good recognition effect on diamond identification and there is littler imageinterference after the identification. Two evaluation indexes: the number of diamond abrasives and theproportion of the diamonds area in the FAP&FAP area, are proposed to evaluate abrasives retainingperformance of FAP.2. The surface of diamond particles was coated with nickel oxide to improve their bondingstrength with the resin. The morphology of coated diamond abrasives, heat treatment and theirinfluence on the machining performance of hydrophilic fixed abrasive pad were studied. Results showthat with the increase of coat ratio, the structure of NiO coated layer become complex gradually.While coat ratio is30%, complex sphere appeared on the surface of diamond and honeycombstructure formed on the surface of sphere convex. This complex structure can increase surfaceroughness of the diamonds that will improve cohering performance between diamond and resin.Afterextending the time of heat treatment and adding the temperature of heat treatment, material removalrate of the diamond coated by30%NiO increases2.4times after changed heat treatment comparedwith unchanged heat treatment.3. K9optical glasses and silicon wafers were chosen as the work-pieces to explore the effect ofmachining sequence on the acoustics emission signal and friction coefficient during lapping on theCP-4polisher. Scanning Electron Microscope (SEM) was employed to analyze the size andmorphology of debris. Results show that material removal rate (MRR) is much different as themachining sequence changes. Compared with the MRR of directly lapped silicon wafer, it decreases a lot if it is lapped after having lapping a K9glass work-piece. Average of surface roughness of directlylapped silicon wafer and K9grass is lower than that lapped after having lapping the other work-piece.The greater size and better edge of debris created during lapping silicon wafer is helpful for theself-conditioning process of hydrophilic FAP.