|About this Abstract
||Materials Science & Technology 2019
||Additive Manufacturing of Metals: Microstructure and Material Properties of Nickel-based Alloys
||Toward an Understanding of Cracking, Scan Strategy and Airfoil Geometry in Electron Beam Powder Bed Additive Manufacturing
||Yousub Lee, Mike Kirka, Ryan Dehoff
|On-Site Speaker (Planned)
The extension of metal additive manufacturing to non-printable Ni-based superalloy (e.g., Mar-M247 and IN738 alloys) is still a challenging issue in electron beam melting (EBM) process. Rapid precipitation of large volume of γ’, non-homogeneous γ’ distribution and existent of γ/ γ’ eutectic phase makes EBM difficult to print the alloys. Since the design of airfoil is complicated, the corresponding complex thermal signature leads to cracking in the geometries under severe mechanical restraints during printing. This work aims to understand the correlation between cracking, scan strategy and part geometry in an actual airfoil. The crack location was monitored via In-situ near infrared camera (NIR) at various heights of the airfoil. A continuum-scale finite element method (FEM) is used to reveal the cracking mechanism. A new scan strategy is tested using FEM model to avoid the cracks from the part.
||Planned: At-meeting proceedings