PURPOSE: To improve an anti-corrosion characteristic of a heat exchanger by a method wherein fins are made of alloy composed of desired wt% of each of Mn, Zn and Ca and the balance of Al added with Zn and a coolant circulation passage is made of a core material including a desired wt% of each of Cu, Mn, Si and Fe and the balance of Al.
CONSTITUTION: Fins 1 are made of alloy having Mn 0.2W1.5 wt.%, Zn 0.5W2.0 wt.%, Ca 0.01W0.5 wt.% and the balance of Al or an alloy added with Zr of 0.2 wt.% or less added to the former alloy. A coolant circulation passage 3 is formed by a brazing sheet having Al-Si-Mg alloy brazing material cladded on both surfaces or one surface of the core material including Cu 0.3W0.9 wt.%, Mn 0.5W1.5 wt.%, Si of 0.2 wt.% or less, Fe 0.2W1.0 wt.% and the balance of Al with a particle diameter of 50W150 μm. With this arrangement, a life of outer surface corrosion-proof characteristic of the coolant circulation passage 3 is improved and a pressure-resistant strength is further improved. In addition, even if a plate pressure at the brazing sheet is made thin by about 0.5 mm or so, the heat exchanger may have a similar pressure-resistant strength and has a superior anti-corrosion characteristic.
ARA CHIAKI
MASUYAMA SHIGEO
KOGA YOSHIAKI
CALSONIC CORP