Dismiss
InnovationQ will be updated on Sunday, Oct. 22, from 10am ET - noon. You may experience brief service interruptions during that time.
Browse Prior Art Database

Densified and Modified Nitrides

IP.com Disclosure Number: IPCOM000076172D
Original Publication Date: 1972-Jan-01
Included in the Prior Art Database: 2005-Feb-24
Document File: 1 page(s) / 11K

Publishing Venue

IBM

Related People

Head, NL: AUTHOR [+2]

Abstract

Hot pressing die materials for use above 1000 degrees C are limited, and often exhibit poor thermal shock resistance and poor thermal conductivity. The materials listed solve these problems for high-temperature firing between 1000 degrees C and 1170 degrees C. Where magnetic oxides are hot pressed, there is no chemical reaction between these materials and the magnetic oxides to be pressed, resulting in cleaner surfaces of better surface finish.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 100% of the total text.

Page 1 of 1

Densified and Modified Nitrides

Hot pressing die materials for use above 1000 degrees C are limited, and often exhibit poor thermal shock resistance and poor thermal conductivity. The materials listed solve these problems for high-temperature firing between 1000 degrees C and 1170 degrees C. Where magnetic oxides are hot pressed, there is no chemical reaction between these materials and the magnetic oxides to be pressed, resulting in cleaner surfaces of better surface finish.

The materials utilized are "densified" silicon nitride (Si(3)N(4)) suitably modified to provide the mechanical properties for use as a mold material, and densified aluminum nitride. The modification involves the use of a fluoride (MgF(2)) and certain mixtures of MgF(2) and MgO to the basic Si(3)N(4) structure. Table I gives the approximate compositions of materials found suitable as mold materials for magnetic metal oxides.

Table I - Composition in Weight Percents.

Compound Basic MgF(2) MgO Si(3)N(4)

A 90.3% 5% 4.7% B 95 5 -

C 95 - 5

1