Processing, characterization, and mechanical properties of beta silicon nitride whisker/silicon nitride matrix composites

Ceramic matrix composites, consisting of β-$\rm Si\sb3N\sb4$ whisker reinforced polycrystalline $\rm Si\sb3N\sb4$, were fabricated with controlled whisker/matrix interfaces, characterized on the microstructural level, and evaluated for mechanical reliability. As-received and coated β-$\rm Si\sb3N\sb4$ whiskers were used to reinforce the $\rm Si\sb3N\sb4$ matrices. Whisker coatings were achieved by low pressure chemical vapor deposition of BN. As-received and coated whiskers and as-received powders were characterized using XRD, XPS, SEM, and TEM techniques. Composite microstructures, including the whisker/matrix interfacial zones, were characterized by SEM and TEM. Mechanical properties of the composites, primarily fracture strength and fracture toughness, were measured and compared to those of the unreinforced matrices.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Applied Mechanics

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2011

Author dc:creator

• Neergaard, Lynn James

Contributors dc:contributor

• Homeny, J.

• Applied Mechanics
• Engineering, Materials Science

Statement dc:rights

• Copyright 1990 Neergaard, Lynn James

Language dc:language

eng

Identifier

AAI9114360
(UMI)AAI9114360

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/23242