Abstract: A high-coercivity thin-film magnetic recording medium, and method of producing the medium, is disclosed. The medium has a sputtered chromium underlayer, preferably about 300-1,000 .ANG. thick, and a sputtered magnetic layer, preferably about 200-800 .ANG. thick, composed of an alloy containing between 70-80% cobalt, 10-20% chromium, 3-20% platinum, and 2-10% tantalum, formed on the chromium underlayer. The medium is characterized by high coercivity, resolution, amplitude and loop squareness value, and low bit shift.

Abstract: A high-coercivity thin-film magnetic recording medium, and method of producing the medium, is disclosed. The medium has a sputtered chromium underlayer, preferably about 300-1,000 .ANG. thick, and a sputtered magnetic layer, preferably about 200-800 .ANG. thick, composed of an alloy containing between 70-80% cobalt, 10-20% chromium, 3-20% platinum, and 2-10% tantalum, formed on the chromium underlayer. The medium is characterized by high coercivity, resolution, amplitude and loop squareness value, and low bit shift.

Abstract: A high-density thin-film magnetic disc and method of producing the disc. In forming the disc, chromium is sputtered onto a smooth-surfaced, non-metallic substrate, such as a glass substrate, first at room temperature, to form a substratum with a random structure, then at a high temperature, to form a chromium underlayer with anisotropic crystal orientation. A cobalt-based alloy is sputtered onto the underlayer to form the thin film magnetic layer. The disc has high coercivity, low bit shift, and can be operated at a flying height of between 2-4 .mu.inches.

Abstract: Method and apparatus for treating the surface of a magnetic disc to remove surface asperities and loosely bound material. The disc is alternatively treated by contact with a pair of moving belt-like tapes, a pair of flying heads, and second contact with the belt-like tape, with the disc carried at a fixed position for rotation in a vertical plane throughout, but rotated at a higher speed during the intermediate flying waffling step. The first and/or second tape-treatment steps can be used to apply a lubricant film to the disc surface.

Abstract: A high-coercivity thin-film magnetic recording medium, and method of producing the medium, is disclosed. The medium has a sputtered chromium underlayer, preferably about 600-1,000 .ANG. thick, and a sputtered magnetic layer, preferably about 200-800 .ANG. thick, composed of an alloy containing between 70-80% cobalt, 10-20% chromium, 8-20% platinum, and 2-10% tantalum, formed on the chromium underlayer. The medium is characterized by high coercivity, resolution, amplitude and loop squareness value, and low bit shift.