ISO 7297:1985 PDF

Overview

ISO 7297:1985 defines the mechanical, physical and magnetic characteristics of a lubricated magnetic disk intended for data storage devices with a nominal outer diameter of 200 mm (7.9 in) and inner diameter 63.5 mm (2.5 in). The standard (prepared by ISO/TC 97) specifies requirements to give satisfactory performance at approximately 95 840 flux transitions per track (title nominally cites 96 000). First published in 1985, ISO 7297 covers dimensional tolerances, environmental and operating conditions, surface quality, magnetic testing and durability criteria for high‑density disk media.

Key topics and technical requirements

• Dimensional and mechanical: outer diameter d3 = 200.00 ± 0.10 mm; inner diameter d2 = 63.500 ± 0.005 mm; thickness 1.905 ± 0.025 mm; concentricity and circularity limits; clamping area specifications.
• Environmental / storage: operating air temperature 15–57 °C, storage −40 to +65 °C; ambient stray field limit at disk surface not to exceed 4 000 A/m (reduced when heads concentrate fields).
• Surface quality: magnetic surfaces roughness