Next Article in Journal
Impact of Angular Distortion on the Fatigue Performance of High-Strength Steel T-Joints in as-Welded and High Frequency Mechanical Impact-Treated Condition
Previous Article in Journal
Laser Powder Bed Fusion of a High Strength Al-Si-Zn-Mg-Cu Alloy
Article Menu
Issue 5 (May) cover image

Export Article

Open AccessArticle
Metals 2018, 8(5), 301; https://doi.org/10.3390/met8050301

Hydrogen-Induced Phase Transformation and Microstructure Evolution for Ti-6Al-4V Parts Produced by Electron Beam Melting

1
School of Nuclear Physics, National Research Tomsk Polytechnic University, Tomsk 634050, Russia
2
Institute of Strength Physics and Materials Science of Siberian Branch of Russian Academy of Sciences, Tomsk 634055, Russia
3
Sports Tech Research Centre, Mid Sweden University, Akademigatan 1, SE-831 25 Östersund, Sweden
*
Author to whom correspondence should be addressed.
Received: 26 March 2018 / Revised: 17 April 2018 / Accepted: 24 April 2018 / Published: 26 April 2018
Full-Text   |   PDF [41635 KB, uploaded 3 May 2018]   |  

Abstract

In this paper, phase transitions and microstructure evolution in titanium Ti-6Al-4V alloy parts produced by electron beam melting (EBM) under hydrogenation was investigated. Hydrogenation was carried out at the temperature of 650 °C to the absolute hydrogen concentrations in the samples of 0.29, 0.58, and 0.90 wt. %. Comparative analysis of microstructure changes in Ti-6Al-4V alloy parts was performed using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD). Furthermore, in-situ XRD was used to investigate the phase transitions in the samples during hydrogenation. The structure of Ti-6Al-4V parts produced by EBM is represented by the α phase plates with the transverse length of 0.2 μm, the β phase both in the form of plates and globular grains, and metastable α″ and ω phases. Hydrogenation to the concentration of 0.29 wt. % leads to the formation of intermetallic Ti3Al phase. The dimensions of intermetallic Ti3Al plates and their volume fraction increase significantly with hydrogen concentration up to 0.58 wt. % along with precipitation of nano-sized crystals of titanium δ hydrides. Individual Ti3Al plates decay into nanocrystals with increasing hydrogen concentration up to 0.9 wt. % accompanied by the increase of proportion and size of hydride plates. Hardness of EBM Ti-6Al-4V alloy decreases with hydrogen content. View Full-Text
Keywords: electron beam melting; additive manufacturing; titanium Ti-6Al-4V alloy; hydrogen; microstructure; phase transitions electron beam melting; additive manufacturing; titanium Ti-6Al-4V alloy; hydrogen; microstructure; phase transitions
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Pushilina, N.; Panin, A.; Syrtanov, M.; Kashkarov, E.; Kudiiarov, V.; Perevalova, O.; Laptev, R.; Lider, A.; Koptyug, A. Hydrogen-Induced Phase Transformation and Microstructure Evolution for Ti-6Al-4V Parts Produced by Electron Beam Melting. Metals 2018, 8, 301.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Metals EISSN 2075-4701 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top