A study on diffusion bonding performance of inconel 617 heat exchanger

This paper proposes diffusion bonding characteristics of a heat exchanger whose material is Inconel. In order to respond to high temperature and pressure operating conditions, the diffusion bonding technology and Inconel 617 material were applied to the heat exchanger. However, it is difficult to estimate how well the diffusion-bonded Inconel heat exchanger is made. In this paper, the bonding performance for the diffusion-bonded heat exchanger was examined and analyzed. The analysis with measuring thermal and mechanical properties such as thermal diffusivity and tensile strength were conducted and parametric studies about bonding temperature and pressing force were carried out. The bonding condition of 1200°C, 50 ton was found to be suitable for this heat exchanger. Through thermal resistance model, impurity management with 10μm level would be expected to be necessary. Besides pressure-resistant test, the deformation in the stacking direction of the plates was found to be important observation element. The heat exchanger was tested for evaluating its capability where the performance showed 10 kW for capacity and 0.7 for effectiveness at 1.5 kg/min. From the results, we were able to establish the base technology for the manufacture of Inconel 617 heat exchanger through the application of the diffusion bonding.