TENSILE FRACTURE CHARACTERIZATION OF BRAZE JOINED COPPER-TO-CFC COUPON ASSEMBLIES

A vacuum brazing process was used to join a broad spectrum of carbon-f iber reinforced carbon matrix composite (CFC) materials, machined into cylindrical coupons, between coupons of oxygen-free copper, the braze alloy was a copper-base alloy which contained only low activation ele ments (Al, Si, and Ti) relative to a titanium baseline specification. This demonstration was of particular importance for plasma facing comp onents (PFCs) under design for use in the Tokamak Physics Experiment ( TPX); the braze investigation was conducted by General Atomics for the Princeton Plasma Physics Laboratory. A tensile test of each brazed as sembly was conducted. The results from the braze processing, testing, and fracture characterization studies of this reporting support the us e of CFC's of varied fiber architecture and matrix processing in PFC d esigns for TPX. Further, the copper braze alloy investigated is now co nsidered to be a viable candidate for a low-activation bond design. Th e prediction of plasma disruption-induced loads on the PFCs in TPX req uires that joint strength between CFC tiles and their copper substrate be considered in design analysis and CFC selection.