| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
Additive Manufacturing: Microstructure and Material Properties of Titanium-based Materials
|
| Presentation Title |
Microstructural Modeling of β to α Transformation Morphologies in Multi-layered Laser Wire Additively Manufactured Ti-6Al-4V Parts |
| Author(s) |
Andrew (Drew) Huck, Amit K. Verma, Anthony Rollett, Brandon Abranovich, Elizabeth Chang-Davidson, Ali Guzel, Jack Beuth, Zhening Yang, Ze Geng, Lonnie Smith, Amaranth Karra |
| On-Site Speaker (Planned) |
Andrew (Drew) Huck |
| Abstract Scope |
The room temperature microstructure of Ti-6Al-4V in multi-bead laser weld deposited builds is characterized by predominantly lamellar α phase growth with interlamellar β within prior β grains. This microstructure is the result of a complex position dependent thermal history, with multiple heating cycles above and near the β transus from subsequent layer depositions. Several α morphologies and different lamellar sizes appear depending on local β character and cooling rates, which can affect the bulk mechanical properties of the material by causing local changes. This work attempts to model location referenced microstructural evolution in laser-wire deposited parts using a classical nucleation and growth model. Additive isothermal time steps in a JMAK type transformation with impingement correction are taken to approximate the cooling curves. Predicted values include area fractions of grain boundary, colony, basketweave, and martensitic α phase, as well as average lamella thickness. |