The influence of impurities on the crystal structure and mechanical properties of additive manufactured U–14 at.% Nb. (15th March 2017)

• Record Type: Journal Article
• Authors: Wu, Amanda S.; Brown, Donald W.; Clausen, Bjørn; Elmer, John W.
• Is Part Of: Scripta materialia. Number 130(2017)
• Page Start: 59
• Page End: 63
• Publication Date: 2017-03-15
• Subjects: Additive manufacturing -- Laser powder processing -- Neutron diffraction -- Superelasticity -- Martensitic phase transformations; Materials -- Periodicals; Metallurgy -- Periodicals; Metalen; Legeringen; Materiaalkunde; Metals, metalworking and machinery industries; Metals; Electronic journals; 620.11
• DOI: 10.1016/j.scriptamat.2016.11.010
• Languages: English
• ISSNs: 1359-6462

Abstract

Abstract: Uranium-niobium alloys can exist with significantly different microstructures and mechanical properties, heavily influenced by thermomechanical processing history and impurities. Here, the influence of Ti and other impurities is studied on uranium-14 at.% niobium additively manufactured using laser powder bed fusion. Two different metallic impurity levels were investigated and a Nb equivalent (Nbeq ) composition is defined to represent the impurities. In-situ neutron diffraction during compression loading shows that increased Nbeq promotes the formation of γ°-tetragonal phase at the expense of α″-monoclinic phase, resulting in 2 × higher yield strength than water quenched α″ and a strain induced transformation to α″ with superelastic strains to 4.5%. Graphical abstract: