Texture Evolution as a Function of Scan Strategy and Build Height in Electron Beam Melted Ti-6Al-4V

Published

June 12, 2021

Author(s)

Alec Saville, Sven Vogel, Adam Creuziger, Jake Benzing, Adam Pilchak, Lee Semiatin, Peeyush Nandwana, Kester Clarke, Jonah Klemm-Toole, Amy Clarke

Abstract

Metal additive manufacturing (AM) enables customizable, on-demand parts, allowing for new designs and improved engineering performance. Unfortunately, the ability to control AM metal alloy microstructures is still lacking, especially when considering crystallographic texture and/or elongated grain morphologies resulting in anisotropy. This work performs corroborative neutron diffraction and large-scale electron backscatter diffraction (EBSD) measurements to assess crystallographic texture in electron beam melted (EBM) Ti-6Al-4V as a function of spot and raster scan strategies with build height. Texture components for all spot melt and raster strategies were evaluated using a triclinic specimen symmetry, and are considerably different than previously reported values from other studies, highlighting the importance of a standard reporting scheme when measuring texture in AM. Texture noticeably varied between scan strategies, but changed minimally as a function of build height. -Ti reconstructions revealed that spot scan strategies produced equiaxed and finer columnar grains with a clear 〖001}〗 _(prior-β) build direction fiber texture, whereas a raster scan strategy produced large columnar grains and a weaker 〖001}〗_β build direction fiber. Grain sizes were also predicted by simulations of solidification conditions during the build process. Smaller, as-solidified grains with a strong 〖001}〗_β fiber orientation preferentially transformed to an unreported 〖011 ̅2} 〗_α fiber texture, which dominated the α-Ti orientations in spot scan strategy colony microstructures.

Citation

Additive Manufacturing

Volume

46

Issue

102118

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.addma.2021.102118

Local Download

Keywords

Additive manufacturing, Ti-6Al-4V, EBM, Texture analysis

Citation

Saville, A. , Vogel, S. , Creuziger, A. , Benzing, J. , Pilchak, A. , Semiatin, L. , Nandwana, P. , Clarke, K. , Klemm-Toole, J. and Clarke, A. (2021), Texture Evolution as a Function of Scan Strategy and Build Height in Electron Beam Melted Ti-6Al-4V, Additive Manufacturing, [online], https://doi.org/10.1016/j.addma.2021.102118, https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=931699 (Accessed December 22, 2024)