Microstructure and Mechanical Property of MXene-Added Ti–6Al–4V Alloy Fabricated by Laser Powder Bed Fusion

Abstract

Laser powder bed fusion (L-PBF) has been utilized to prepare a high-strength titanium alloy builds using 0.3 mass% MXene-decorated Ti–6Al–4V alloy particles produced by an electrostatic self-assembly. The MXene/Ti–6Al–4V powder mixture had similar spherical morphology and powder size, while showing higher laser absorptivity as compared with the Ti–6Al–4V powders. Under high-energy laser irradiation, MXene was fully decomposed and uniformly dissolved into the Ti matrix. Microstructure observations illustrated that the MXene/Ti–6Al–4V build was completely consisted of ultrafine carbon-saturated martensite structures. Consequently, the MXene/Ti–6Al–4V build exhibited a high tensile strength of ∼1.4 GPa, attributing to the refinement of martensitic structure and the solid solution strengthening of carbon. These findings of this study may broaden the potential application of MXene and pave up the way towards the fabrication of advanced titanium parts via L-PBF.

(a) FE-SEM image of the MXene/Ti–6Al–4V mixed powder; (b) TEM image of the MXene/Ti–6Al–4V build; (c) tensile stress-plastic strain curves of the Ti–6Al–4V and MXene/Ti–6Al–4V builds; (d) comparisons in the UTS versus plastic elongation for additively manufactured Ti–6Al–4V alloys and TMCs.