Nkk Corporation

Other

Toshio Sakiyama

Hiroyoshi Suenaga

Kuninori Minakawa

Hideaki Fukai

Kenji Morita

Masanori Ohmura

Iwao Ida

Hiroyoshi Takeuchi

Yoko Okano

Hitoshi Nagashima

Masakuni Takagi

A method of manufacturing a magnetic disk substrate made of titanium, in which chemical etching is performed on a titanium disk for magnetic disk substrate, thereby removing a surface portion thereof having a thickness of at least 2 nm, and the new surface of the titanium disk, formed by the chemical etching, is anodized, thereby forming anodized film on the titanium disk.

Method of manufacturing a magnetic disk substrate of titanium

According to a mirror surface polishing process of the present invention, it is possible to produce Ti-made magnetic disc substrate which have the excellent flatness degree and surface roughness in that the average roughness is not more than 0.05 .mu.m and the flatness degree of the outer periphery is not more than 0.15 .mu.m.

Method for mirror polishing of ti-made magnetic disk substrate

After the surface roughness of a titanium substrate is set to be R.sub.max .ltoreq.0.08 .mu.m, a hardened layer having a hardness of H.sub.v .gtoreq.250 is formed thereon to have a thickness of 50 to 250 .mu.m by sputtering, thereby manufacturing a titanium magnetic disk substrate.

Method of manufacturing titanium magnetic disk substrate

Growing community of inventors

Tokyo, Japan

Toshio Sakiyama