Improved performance of brazed plate heat exchangers made of stainless steel type EN 1.4401 (UNS S31600) when using a Iron-based braze filler

摘要

The mechanical properties of brazed plate heat exchangers, made of stainless steel plates type EN 1.4401, brazed with a new iron-based braze filler "AlfaNova", have been evaluated. The results were compared with heat exchangers brazed with a copper (pure copper) and a nickel-based (MBF 51) braze filler. Their resistance against pressure- and temperature fatigue, which are important for the lifetime of a heat exchanger, and the burst pressure, which is important for pressure vessel approvals, were tested and evaluated. It was found that the pressure fatigue resistance was extraordinary good for the heat exchangers brazed the iron-based filler and its temperature fatigue resistance was better than those brazed with nickel-based braze filler and slightly lower than those brazed with copper. The highest burst pressures were achieved for the copper brazed units followed by the iron-brazed units and rearmost the nickel-brazed units.