Abstract: This is a process which provides the first essentially continuous high tin flow soldering method for attaching copper-based fins to non-copper-based tubing. This invention avoids sludge buildup in the reservoir and generally avoids lead carbonate formation when the heat produced having a braze-like joint with eta phase layers exchanger is in service. In addition, a novel structure is adjacent to copper-containing surfaces. The invention utilizes an essentially lead-free, high tin solder cascade onto a preferably cool tube, genrally with a limited time of contact between the liquid solder and the tube, and with a combination air quench and wipe to remove excess solder and solidify the remaining solder. Thus a braze-like joint is achieved having better heat conduction and closer thermal expansion match. This finned heat exchanger tubing is generally useful for liquid to gas-type heat exchangers.

Abstract: This is an article and process which provide the first essentially continuous high tin flow soldering method for attaching copper based fins to copper based tubing. This invention avoids sludge buildup in the reservoir and generally avoids lead carbonate formation when the heat exchanger is in service. In addition, a novel structure is produced having a braze like joint with eta phase layers adjacent to the copper based surfaces. The invention utilizes an essentially lead free, high tin solder cascade onto a preferably cool tube, generally with a limited time of contact between the liquid solder and the tube, and with a combination air quench and wipe to remove excess solder and solidify the remaining solder. Thus a braze like joint is achieved having better heat conduction and closer thermal expansion match. This finned heat exchanger tubing is generally useful for liquid to gas type heat exchangers and especially useful for hydrogen coolers for electrical generators.

Abstract: A joint is provided which permits clad members to be welded together and later used in a corrosive environment without subsequent degradation of the base or cladding materials. The use of an intermediate metallic layer prevents the close proximity of galvanically incompatible materials in brackish or saline environments.