Abstract
In the second report, the relationship between lapped quantity and lapping conditions was calculated on the assumption that the whole load was supported between specimen and abrasives. When lap makes a direct contact with specimen, the lapped quantity will be reduced. To investigate the mechanism of lapping, the load supported between lap and specimen must be measured. Experiments of measuring the electrical contact resisitance between lap and specimen showed that direct contact ocurred in lapping with very fine abrasives (e.g. Cr2 O2) because of embedding of abrasives into graphite included in cast iron lap, and that it did not occur in lapping with GC or WA. From this point of view, the relationship between lapped quantity and mixing ratio was discussed. It was also indicated that the lapping condition could be observed by measuring the electrical contact resistance.
