|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Additive Manufacturing of Metals: Fatigue and Fracture
||Investigating Defect Formation Mechanisms in Powder-bed Metal Additive Manufacturing Using Synchrotron-based High-speed X-ray Radiography and Microtomography
||Ross Cunningham, Cang Zhao, Tao Sun, Anthony Rollett
|On-Site Speaker (Planned)
Additive manufacturing (AM) provides the means to fabricate complex metallic parts with reduced time to market and material waste. However, while most mechanical properties of AM parts meet or exceed those of conventional materials, fatigue resistance in as-built parts has been inferior and unpredictable due to the large and variable presence of porosity. This presents a challenge for the qualification of any load bearing part without extensive post-processing and inspection. Further understanding of the underlying mechanisms behind defect formation will assist in process adjustments to minimize defects without relying on post-processing. This work focuses on newly developed capabilities at Argonne National Lab's Advanced Photon Source to observe porosity developing in a moving melt pool using high-speed X-ray radiography and a custom built in-beamline laser powder bed fusion (LPBF) system. Additionally, X-ray microtomography is used to observe the evolution of porosity through each stage of post-processing (as-built, HIP, post-HIP heat treatments).
||Planned: Supplemental Proceedings volume