| About this Abstract |
| Meeting |
2020 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing Fatigue and Fracture IV: Toward Confident Use in Critical Applications
|
| Presentation Title |
Fatigue Crack Growth Properties of Selective Laser Melting Produced Nickel and Titanium Based Alloys |
| Author(s) |
Jamie J. Kruzic, Halsey E. Ostergaard, Tarik Hasib |
| On-Site Speaker (Planned) |
Jamie J. Kruzic |
| Abstract Scope |
Selective laser melting (SLM) produces unique microstructures (e.g., epitaxial columnar grains, texture, etc.) that influence mechanical properties. In this work, the fatigue crack growth properties of SLM produced Alloy 718 and Ti-6Al-4V were examined at room temperature with various cracking orientations relative to the build plane and various post heat treatments, including hot isostatic pressing (HIP). Both materials showed very weak anisotropy in their 25°C fatigue growth rates. For Alloy 718, HIPing was found to recrystallize much of the columnar microstructure and mostly eliminate the weak anisotropy in growth rates seen for the non-HIPed structure; however, growth rates and thresholds remained well below that of wrought material. At 650˚C, anisotropy in fatigue crack growth rates became significant. For Ti-6Al-4V, fatigue thresholds increased with increasing alpha lath thickness and decreasing strength. Microstructure analysis, fractography, and observations of crack profiles were used to understand the microstructure influence on fatigue crack growth. |
| Proceedings Inclusion? |
Planned: Supplemental Proceedings volume |