Method and apparatus for enhanced convection brazing of aluminum

Abstract

A convection furnace is provided for brazing workpieces in a heated recirculating atmosphere, in which the workpieces are positioned within a heating chamber of the furnace and are alternately heated from different sides in a controlled manner such that a substantially uniform temperature is maintained throughout the workpieces while their temperatures are increased by the heated atmosphere, preferably an inert gas. The braze furnace is adapted to intermittently divert the heated atmosphere to one side of the heating chamber, through one or more stacked workpieces, to an opposite side of the heating chamber. As such, a pulsed multi-directional convective atmosphere flow is achieved through the workpieces that promotes a more rapid and uniform heat transfer to the workpieces. As a result, each structure as a unit reaches a suitable braze temperature more effectively and efficiently than previously possible. The enhanced capability of the furnace also enables structures to be stacked on top of each other, thereby substantially increasing furnace throughput.