PURPOSE: To improve the corrosion resistance and thermal conductivity of a fin by forming a fin of a copper allay in which the cementating layer of zinc is formed on the surface and contg. specified amounts of tin and lead.
CONSTITUTION: The cementating layer of zinc is formed on the surface of a copper allay contg., by weight, 0.01 to 0.05 tin and 0.001 to 0.01% lead. By constituting a fin by the above material, the fin of a heat exchanger having excellent corrosion resistance and high thermal conductivity can be obtd. In the case the content of tin and lead in the above copper allay is regulated to the lower limit or less, in either case, its heat resistance deteriorates. In the case it is regulated to more than the upper limit, in either case, its thermal conductivity and workability deteriorate Furthermore, together with zinc, tin, nickel or phosphorus may be diffused.
SASAKI HAJIME
SHIMADA TAKESHI
