Microstructurally Developed Toughening Mechanisms in Ceramics. Fracture Toughness of Si3N4 as a Function of the Initial Alpha-Phase Content.
Abstract
Mixtures of high alpha-Si3N4 and high Beta-Si3N4 powders were hot-pressed with 5 w/o MgO. The critical stress intensity factor of this series of materials increased from 4.16 MPa/m sq to 6.0 MPa/m sq as the initial alpha-Si3N4 increased from 26% to 70% respectively. These results are consistent with the concepts that the alpha/Beta ratio governs the aspect ratio of the fibrous grains and that fibrous fracture is responsible for the high fracture toughness of Si3N4. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 1978
- Accession Number
- ADA057241
Entities
People
- F. F. Lange