About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Additive Manufacturing Fatigue and Fracture: Effects of Surface Roughness, Residual Stress, and Environment
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Presentation Title |
Globularization of Alpha Phase in Additively Manufactured Ti-6Al-4V Alloys and Effects on High-Cycle and Very-High-Cycle Fatigue |
Author(s) |
Reza T. Mousavian, Anthony G. Spangenberger, Austin Mann, Cory Cunningham, Diana A. Lados |
On-Site Speaker (Planned) |
Reza T. Mousavian |
Abstract Scope |
The high cooling rates during the laser powder bed fusion (LPBF) fabrication of Ti-6Al-4V result in a martensitic alpha’ microstructure with acicular morphology, which causes undesirable ductility and toughness of the as-fabricated material. In this study, a novel heat-treatment process was developed for the LPBF material to create a bimodal microstructure, consisting of globular primary alpha grains and lamellar alpha+beta colonies. Optical and scanning electron microscopy studies, including electron backscatter diffraction and energy dispersive X-ray spectroscopy, were performed to characterize both the as-fabricated and heat-treated microstructures. Further, the fatigue behavior of the as-fabricated and heat-treated Ti-6Al-4V alloys was investigated in the high-cycle and very-high-cycle regimes using conventional and ultrasonic fatigue testing (R=-1). The effects of the primary alpha grains globularization on the fatigue response of the LPBF materials were systematically assessed, and the results were compared to those of a solution treated and overaged wrought Ti-6Al-4V with bimodal microstructure. |
Proceedings Inclusion? |
Planned: |
Keywords |
Additive Manufacturing, Titanium, Mechanical Properties |