Hydrogen embrittlement of electron beam melted Ti–6Al–4V

Abstract

Environmental-assisted degradation in hydrogen environment, also known as hydrogen embrittlement (HE), has a very important role on physical and mechanical properties of structural materials in the presence of hydrogen. In this research the interactions of high and low fugacity hydrogen with electron beam melted (EBM) Ti–6Al–4V alloy were studied and compared to conventionally manufactured alloy. Parts produced by additive manufacturing (AM) experience relatively high cooling rates and possess unique microstructure features, which might alter the intrinsic properties of the material. Our research describes in details the impact of hydrogen on EBM Ti–6Al–4V alloy by means of hydrogen trapping. The interactions of hydrogen with the material were studied by thermal desorption spectroscopy (TDS), X-ray diffraction, and microstructural observations. Our results suggest that EBM Ti–6Al–4V alloy with relatively fine microstructure has a better resistance for hydrogen induced damage in comparison to a wrought alloy.

Keywords

• Hydrogen trapping
• Additive manufacturing (AM)
• Ti–6Al–4V
• Thermal desorption spectrometry (TDS)