| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing an inexpensive, highly corrosion resistant heat exchanger formed of stainless steel. SOLUTION: A chromium brazing filler metal layer 21 is formed after applying the Cr electroplating of a plating thickness of 15 μm on both end faces of first and second forming stainless steel plates 1 and 2 alternately stacked on each other in the thickness direction, and then a nickel brazing filler metal layer 22 is formed after applying the Ni-P plating of a plating thickness of 35 μm on the chromium brazing filler metal layer 21. The highly corrosion resistant heat exchanger is manufactured by applying the integral brazing with the chromium brazing filler metal layer 21 and the nickel brazing filler metal layer 22 interposed between the first and second forming plates 1 and 2. A highly corrosion resistant brazing filler metal 31 having an alloy composition consisting of Ni-Cr28-P8, etc., is obtained on both end faces of the first and second forming plates 1 and 2. A fine metal structure in the highly corrosion resistant brazing filler metal 31 can be realized, and generation of cracks in the interface of the metal structure can be reduced. |
