Alumina base substrate of recording head and process for the production thereof
US4598052A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 29, 1985 |
| Grant date | Jul 1, 1986 |
| Priority date | — |
| Expiry date | Apr 29, 2005 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC04B35/111
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
An alumina base substrate material for recording heads, which comprises a densely sintered body consisting essentially of: PA0 per 100 parts by weight of a base component of 30 to 40% by weight of a titanium compound having TiO.sub.2 to (TiC+TiO.sub.2) percentage of 5 to 15% by weight and the balance being Al.sub.2 O.sub.3, PA0 components A, B and C, provided that the A to B ratio is within a hatched KLMN area in FIG. 1, in the following given parts by weight, and PA0 oxidic impurities in amounts of no higher than 0.2% by weight based on the total composition, PA0 said sintered body having an average crystal grain size of no higher than 1.3 microns, a porosity per area of no higher than 0.5%, a bending strength of at least 70 kg/cm.sup.2 and a hardness H.sub.R A of at least 93.0: wherein PA0 component A is at least one of spinels expressed by RO-Al.sub.2 O.sub.3, where R is at least one of Mg, Mn, Ni and Co, in an amount of 2.0 to 17.5 parts by weight, PA0 component B is 0.2 to 2.0 parts by weight of ZrO.sub.2, and PA0 Component C is 0.05 to 2.0 parts by weight of Y.sub.2 O.sub.3.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.