Reactive alloy melt infiltration for SiC composite matrices: Mechanistic insights
Abstract
A comparative study of reactive melt infiltration using Si and Si‐Y alloys is presented to provide insight into the governing processes that control the effectiveness of the melt interaction with a carbonaceous preform and the temperature capability of the SiC matrix for ceramic matrix composites. Through experiments on two substantially different scales of capillaries in porous graphite tubes using Si and Si‐Y alloys, the current study has characterized the phenomena that play a role in the infiltration of the melt and its reaction with the preform. It is shown that (i) the interface reaction controls wetting in both large and small capillaries and the climb rate is enhanced by the presence of Y; (ii) reaction choking occurs at critical throats within the pore network, usually behind the infiltration front; and (iii) different residual silicides can form during reaction and upon cooling. A potential mechanism for SiC growth is described, and the implications for the interplay between SiC growth and infiltration are discussed.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Aug 29, 2017
- Source ID
- 10.1111/jace.15167
Entities
People
- Carlos G. Levi
- Frank W. Zok
- Rebecca Reitz
Organizations
- Division of Materials Research
- Office of Naval Research
- University of California, Santa Barbara