MAGNETIC DISK AND SURFACE PROCESSING THEREOF AND MAGNETIC DISK APPARATUS

PURPOSE:To improve floating characteristic by making smooth the internal and external circumferences of a magnetic disk. CONSTITUTION:A substrate 1 having completed the cutting process is supported by three rotatable rollers 2, a polisher made of unwoven cloth is bonded on the surface of tools 3, 5, and the internal circumference portion and external circumference portion of the substrate 1 are ground while a grinding agent dispersing free grains is being supplied. The chamfer portion of substrate is cut or ground with the edge portion of the rotating tool which is formed like the chamfer portion. Next, with a both-side simultaneous processing machine, both sides of the substrate 1 are ground using a tool of an elastic grind stone GC#1500 on the upper and lower stools, polishers made of unwoven cloth is attached to both upper and lower stools with the similar both side simultaneous processing machine and the substrate 1 is ground for the purpose of cleaning with a grinding agent where aluminum grains in the grain size of 3mum is dispersed. Thereby, the surface of the internal and external circumferences of disk is made smooth with less contamination or fitting of foreign matters during the manufacture. Accordingly, cleaning in each process can be realized effectively and a high quality magnetic disk having improved the floating characteristic can be obtained.