Coatings and joining for SiC and SiC-composites for nuclear energy systems
C.H. Henager Jr.a, , , Y. Shina, Y. Blumb, L.A. Giannuzzic, B.W. Kempshalld and S.M. Schwarzd
aPacific Northwest National Laboratory, 902 Battelle Blvd., MS P8-15, Richland, WA 99352-0999, USA bSRI, International Menlo Park, CA 94025, USA cFEI Company, 5350 NE Dawson Creek Drive, Hillsboro, OR 97124, USA dUniversity of Central Florida and NanoSpective, Inc., Orlando, FL 32826, USA
Available online 30 March 2007.
Coatings and joining materials for SiC and SiC-based composites for nuclear energy systems are being developed using preceramic polymers filled with reactive and inert powders, and using solid-state reactions. Polymer-filled joints and coatings start with a poly(hydridomethylsiloxane) precursor, such that mixtures of Al/Al2O3/polymer form a hard oxide coating, coatings made with Al/SiC mixtures form a mixed oxide–carbide coating, while coatings made with SiC/polymer form a porous, hard carbide coating. Joints made from such mixtures have shear strengths range from 15 to 50 MPa depending on the applied pressure and joint composition. The strongest joints were obtained using tape cast ribbons of Si/TiC powders such that a solid state displacement reaction at 1473 K and 1673 K using 30 MPa applied pressure resulted in shear strengths of 50 MPa, which exceeds the shear strength of SiC/SiC composite materials. However, the polymer joints are much easier to apply and could be considered for field repair.
Journal of Nuclear Materials Volumes 367-370, Part 2, 1 August 2007, Pages 1139-1143 Proceedings of the Twelfth International Conference on Fusion Reactor Materials (ICFRM-12), Proceedings of the Twelfth International Conference on Fusion Reactor Materials (ICFRM-12)