Microstructure control of silicon nitride by seeding with rodlike [beta]-silicon nitride particles

Journal Article · Fri Jul 01 04:00:00 EDT 1994 · Journal of the American Ceramic Society; (United States)

DOI:https://doi.org/10.1111/j.1151-2916.1994.tb07062.x· OSTI ID:7166687

Hirao, Kiyoshi; Nagaoka, Takaaki; Brito, M E; Kanzaki, Shuzo ^[1]

---

1. National Industrial Research Inst. of Nagoya (Japan)

The effect of seeding on microstructure development and mechanical properties of silicon nitride was investigated by the use of morphologically regulated rodlike [beta]-Si[sub 3]N[sub 4] single-crystal particles with a diameter of 1 [mu]m and a length of 4 [mu]m as seed crystals. Silicon nitride with a bimodal microstructure was fabricated under a relatively low nitrogen gas pressure of 0.9 MPa owing to the epitaxial growth of [beta]-silicon nitride from the seed particles. Grain growth from seeds followed the empirical equation D[sup n] [minus] D[sub 0][sup n] = kt, with growth exponents of 3 and 5 for the c-axis direction and the a-axis direction, respectively, being analogous to the kinetics of matrix grain growth. By seeding morphologically regulated particles, fracture toughness of silicon nitride was improved from 6.3 to 8.4--8.7 MPa[center dot]m[sup 1/2], retaining high strength levels of about 1 GPa.

• OSTI ID: 7166687
• Journal Information: Journal of the American Ceramic Society; (United States), Journal Name: Journal of the American Ceramic Society; (United States) Vol. 77:7; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360201 -- Ceramics
Cermets
& Refractories-- Preparation & Fabrication
360202* -- Ceramics
Cermets
& Refractories-- Structure & Phase Studies
360203 -- Ceramics
Cermets
& Refractories-- Mechanical Properties
CERAMICS
FABRICATION
FRACTURE PROPERTIES
MECHANICAL PROPERTIES
MICROSTRUCTURE
NITRIDES
NITROGEN COMPOUNDS
PNICTIDES
SILICON COMPOUNDS
SILICON NITRIDES