Bonding porous carbon and copper-rich workpieces, e.g. for use in heat exchangers, involves soldering using alloy based on copper and silicon, ensuring good heat transfer

摘要

The use of an alloy (I) based on copper (Cu) and silicon (Si), containing (atomic basis) 25-60% Cu, 40-75% Si and at least 95% Cu plus Si (preferably 60% Cu and 40% Si), is claimed for bonding porous carbon workpiece(s) to copper-rich metallic workpiece(s). Independent claims are included for: (1) a soldering paste (A), comprising a mixture of powdered (I) and an inorganic binder; (2) a method for bonding a porous carbon workpiece to a copper-rich metallic workpiece, involving (a) depositing (I) or (A) on the carbon workpiece in an amount (as (I)) of 50-500 mg/cm 2>, (b) heating under vacuum or an inert atmosphere to melt (I) or (A), (c) contacting the asssembly with the other workpiece and (d) heating the assembly under vacuum or an inert atmosphere at a temperature below the m.pts. of the copper workpiece and (I) or (A); (3) an assembly consisting of the porous carbon and copper-rich workpieces, bonded at their interface by a fused and solidified layer of (I); and (4) a device comprising at least one of the assemblies.