Multi-material additive manufacturing processes enable tailor made parts with locally varying properties that fit functional requirements. For example, the excellent creep and corrosion resistance of Inconel alloys can be used to line the walls of a heat exchanger, whereas less expensive steels can be used for the infill. While proper bonding between the metal components is desired, overly large melt pools with chaotic flow patterns can smear the design material layout. In this work, we investigate how two of the most common alloys (SS316 and IN718) can be printed to form a metal composite with distinct interfaces. To investigate how diffusion and convection mixing in the melt-pool affect the final multi-metal print, a state-of-the-art Computational Fluid Dynamics (CFD) model is built in FLOW-3D AM. This model accounts for thermophysical material properties as well as physical phenomena including solidification, liquid-vapor phase change, recoil pressure, Marangoni effects, and radiative heat transfer. The simulation results qualify the relation between the process parameters and the ability to reproduce design patterns. This methodology can be expanded for optimization studies of process parameters for manufacturing multi-material parts.
Learning Objectives:
- Upon completion, participants will be able to understand how the computational analysis of the melt pool can aid in the design of additive manufacturing processes.
- Upon completion, participants will be able to understand what some of the challenges are related to the construction of multi-material metal prints.
