Development of Corrosion Resistant Aluminum Heat Exchanger, Part 1: Development of New Aluminum Alloy Sheets for Sacrificial Anode

The sacrificial anodic effect of Al-Zn alloy reduces markedly in aluminium heat exchanger as car air-conditioner manufactured by vacuum brazing conventionally used, as zinc elements preferentially evaporate in vacuum-heating. It was found that Al-Sn alloy had superior electrochemical characteristics than Al-Zn alloy (AA7072) as the sacrificial anodic material used in vacuum brzing.

According to many experimental results, the new brazing sheet-fin with Al-Mn-Sn alloy core metal has been developed. This fin has favorable formability and prominent sacrificial anodic effect. Therefore, this fin is excellent material for car air-conditioner manufactured by vacuum brazing.