Development of a high-temperature Inconel 625 heat exchanger by model design and binder jetting additive manufacturing
Wenchao Du, Joseph Hayes, Kyle Myers, Bipul Barua, Wenhua Yu, Dileep Singh
Abstract
• Study of process parameter effects on the material properties of binder-jet printed Inconel 625. • Modelling study of geometrical effects on the mechanical and thermal performances of flow channels. • Prototyping and testing of a one-piece Inconel 625 heat exchanger for harsh environments. A nickel-based Inconel 625 superalloy heat exchanger for high-temperature applications was developed via binder jetting additive manufacturing. The material properties were characterized first on printed and sintered parts. Two sintering temperatures were used to investigate the effects of the temperature on densification and microstructure. For channel geometry design, the heat transfer capabilities of the heat exchanger were optimized for the cross-section geometry of fluid flow channels in a counterflow configuration, and a stress analysis was conducted to investigate the effects of channel geometry. After headers were incorporated into the heat exchanger as a one-piece component, a prototype was printed. A complete depowdering was achieved via compressed air blowing, and sintering was performed with the developed profile. Ultimately, a one-piece heat exchanger with a nearly full density was obtained. Heat transfer tests were performed on this unit, and the results were compared with those from the simulations. In this study, systematic processes were developed for an additively manufactured Inconel-based heat exchanger for high-pressure, high-temperature heat transfer applications.