Induction Brazing Process Research Articles

Brazing of copper-alumina alloys

The successful use of GlidCop Al-15 in tokamak fusion reactors depends on the ability to join the alloy during fabrication without destroying its properties. An induction brazing process using a 50 kW induction furnace with an oval shaped helical coil and the silver-base brazing alloy, BAg-5, has been developed. This process minimizes the time required at elevated temperatures during the brazing process in order to eliminate excessive oxidation associated with furnace brazing. Induction brazing severely restricts the time for silver ingression along the grain boundaries. Examination of the microstructure of induction brazed joints indicated that the brazing procedure produced virtually no diffusion zone at the copper-silver interface. Microhardness measurements indicated little or no difference along the length of the alloy after brazing. Tensile tests of induction brazed lap joints have indicated good braze properties.