4.7 Article

Transformations of Ti-5Al-5V-5Cr-3Mo powder due to reuse in laser powder bed fusion: A surface analytical approach

Journal

APPLIED SURFACE SCIENCE
Volume 564, Issue -, Pages -

Publisher

ELSEVIER
DOI: 10.1016/j.apsusc.2021.150433

Keywords

ToF-SIMS; XPS; Surface oxide; Ti-Al alloy powder feedstock; Additive manufacturing

Funding

  1. U.S Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists, Office of Science Graduate Student Research (SCGSR) Program
  2. Department of Energy [DE-SC0014664]
  3. Laboratory Directed Research and Development program at Lawrence Livermore National Laboratory [20-SI-004]
  4. U.S. Department of Energy by Lawrence Livermore National Laboratory [DE-AC52-07NA27344]

Ask authors/readers for more resources

A multimodal characterization of new and reused Ti5553 powder reveals changes in surface oxide composition due to reuse, with Al oxide regions becoming more hydroxylated, potentially affecting recyclability. Further study of surface transformations may help eliminate unnecessary variation in LPBF.
Reactive Ti-5Al-5 V-5Cr-3Mo (Ti5553) alloy feedstock powder is used in laser powder-bed fusion (LPBF). Due to the large quantity of powder necessary for LPBF, powder is reused numerous times under oxidizing environments. Transformations to the powder's native surface oxide may impact the LPBF process and lead to deviations from expected behavior of printed parts. Here, we present a multimodal characterization of new and reused powder by combining X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and transmission electron microscopy (TEM) of focused ion beam (FIB)-prepared cross sections of individual powder particles to understand how the surface oxide composition changes, grows, and becomes hydroxylated and hydrated due to reuse. We show that the native oxide film of Ti5553 powder is a hydroxylated mixed oxide composed of TiO2 and Al2O3 that grows from 5.6 +/- 0.7 nm to 8.3 +/- 1.1 nm due to reuse. Al oxide regions of the surface oxide become more hydroxylated during reuse in comparison to Ti oxide regions. This indicates that an outer oxide of pure TiO2 may enhance recyclability of Ti5553 powder while the presence of Al oxides may decrease recyclability. Further characterization of surface transformations due to recyclability may eliminate unnecessary variation in LPBF.

Authors

I am an author on this paper
Click your name to claim this paper and add it to your profile.

Reviews

Primary Rating

4.7
Not enough ratings

Secondary Ratings

Novelty
-
Significance
-
Scientific rigor
-
Rate this paper

Recommended

No Data Available
No Data Available