Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength
Abstract
A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength are disclosed. The powder mixture includes (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12m[sup 2]g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder. No Drawings
- Inventors:
- Issue Date:
- OSTI Identifier:
- 7085450
- Patent Number(s):
- 5049530
- Application Number:
- PPN: US 7-596256
- Assignee:
- GTE Laboratories Incorporated, Waltham, MA (United States)
- DOE Contract Number:
- AC05-84OR21400
- Resource Type:
- Patent
- Resource Relation:
- Patent File Date: 12 Oct 1990
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 36 MATERIALS SCIENCE; COMPOSITE MATERIALS; FABRICATION; SILICON NITRIDES; BINDERS; COMPACTING; FIBERS; FRACTURE PROPERTIES; ORGANIC COMPOUNDS; PARTICLE SIZE; WHISKERS; CRYSTALS; MATERIALS; MECHANICAL PROPERTIES; MONOCRYSTALS; NITRIDES; NITROGEN COMPOUNDS; PNICTIDES; SILICON COMPOUNDS; SIZE; 360601* - Other Materials- Preparation & Manufacture
Citation Formats
Huckabee, M L, Buljan, S T, and Neil, J T. Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength. United States: N. p., 1991.
Web.
Huckabee, M L, Buljan, S T, & Neil, J T. Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength. United States.
Huckabee, M L, Buljan, S T, and Neil, J T. Tue .
"Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength". United States.
@article{osti_7085450,
title = {Power mixture and green body for producing silicon nitride base articles of high fracture toughness and strength},
author = {Huckabee, M L and Buljan, S T and Neil, J T},
abstractNote = {A powder mixture and a green body for producing a silicon nitride-based article of improved fracture toughness and strength are disclosed. The powder mixture includes (a) a bimodal silicon nitride powder blend consisting essentially of about 10-30% by weight of a first silicon nitride powder of an average particle size of about 0.2 [mu]m and a surface area of about 8-12m[sup 2]g, and about 70-90% by weight of a second silicon nitride powder of an average particle size of about 0.4-0.6 [mu]m and a surface area of about 2-4 m[sup 2]/g, (b) about 10-50 percent by volume, based on the volume of the densified article, of refractory whiskers or fibers having an aspect ratio of about 3-150 and having an equivalent diameter selected to produce in the densified article an equivalent diameter ratio of the whiskers or fibers to grains of silicon nitride of greater than 1.0, and (c) an effective amount of a suitable oxide densification aid. The green body is formed from the powder mixture, an effective amount of a suitable oxide densification aid, and an effective amount of a suitable organic binder. No Drawings},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Sep 17 00:00:00 EDT 1991},
month = {Tue Sep 17 00:00:00 EDT 1991}
}