It is a contradiction to achieve a high material removal rate and a super smooth surface in lapping of magnetic head. Study on material removal is helpful to improve the lapping process. The float-piece polisher armed with conditioning ring was used in GMR hard disk sliders’lapping. Electroluminescent SEM and AFM were used to measure the sliders’surface. The topography of sliders was different when the work conditions such as topography of pad, slurry and lapping pressure changed. There are Nicks and a few micro indentations were observed, it indicated that the surface material was removed in micro-cut mainly by abrasive. The number and the depth of the nicks and micro indentations on the sliders’surface varied with the lapping condition, and an ideal sliders surface could be achieved in an appropriated lapping condition. Armed with nano indentation hardness, advanced research was carried out to investigate the effect of pad, slurry and lapping pressure on the material removal rate. A material removal rate model was developed and used to estimate the surface roughness. The model is consistent with experiments. According to the model, the lapping techniques can be optimized to obtain excellent slider surface and high efficiency simultaneously.
