Ultrasonic polishing of giant magnetic resistance magnetic recording heads for hard discs

Abstract The material removal rate (MRR) is very low and it is difficult to achieve a pole tip recession (PTR) smaller than 10 nm with conventional polishing. Ultrasonics was applied to the recording head polishing with a float-piece polisher to find a new method to reduce the PTR and increase the MRR. The power of ultrasonics used in the experiment was 35 W, and its frequency was 40 kHz. Two pieces of rowbars were fixed on the specimen holder, and the rotational speed of the plate was 25 r/min. The MRR and the roughness of the surface were improved, and the PTR was reduced to 1-2 nm.