Abstract: Magnetohydrodynamic devices using hot ionized gas as working fluid require channel refractories, insulators, and electrodes to be cooled at their reverse sides in order to carry away heat flux fast enough to keep obverse sides below melting point, since gas temperatures of roughly 2500.degree. C. exceed melting points of any available metals or ceramics. Common procedure of brazing ceramic to metal backing (which is more conveniently fastened in apparatus and cooled) creates only partially solvable problem of differential thermal expansion, or bad fit. Ceramic reverse is grooved with dovetailed or convergent slots against which brazing stock is placed for brazing to metal backing. During brazing, molten braze alloy enters grooves and forms mechanical lock which on test proves stronger than ceramic itself.

Abstract: Copper backings brazed to ceramic parts exposed to high-temperature oxidizing high-velocity gases must be secured, for mounting purposes, to water-cooled fixed support, with high thermal conductance between backing and support. Prior art practice of brazing backing to support is inconvenient, making subsequent removal difficult, and disadvantageous in requiring that support be heated to brazing temperature (which may weaken support by annealing it). Invention teaches channel-shaped clip, on back of backing, whose legs are spread slightly to be inserted in mating slots in support face. All mating surfaces are tinned with lead-tin eutectic solder. If mere mechanical contact provides adequate thermal conductance between backing and support, solder remains unmelted; but if mechanical contact is imperfect temperature of backing will rise, and solder will melt and bridge gap between backing and support, raising thermal conductance.