Magnetic disk substrate of fiber-reinforced plastic

US4415942A · kind A · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Albert Frosch
• Holger Hinkel · Böblingen, DE
• Georg Kraus · Konz, DE

Key dates

• Filing date: Jul 28, 1981
• Grant date: Nov 15, 1983
• Expiry date: Jul 28, 2001

Classification

• Technology area (CPC G): Physics
• CPC primary: G11B5/82
• WIPO field: Audio-visual technology
• WIPO sector: Electrical engineering

Abstract

The substrate 1 for magnetic disks takes the form of a laminate made up of a plurality of individual thin, fiber-reinforced, anisotropic and unidirectional lamellae. These lamellae are arranged staggered on top of each other at few angular spacings, i.e., at great angles of up to 60.degree., and are finally pressed together. The outer layers and lamellae, respectively, may be reinforced by stronger fibers or other material, such as carbon fibers outside and glass fibers inside, to influence the flexural modulus and the shearing modulus independently of each other. This makes for a substrate which consists of anisotropic material, whose characteristics are essentially isotropic, which is lighter than previously used substrates, and which has a higher critical number of revolutions.