Microstructures and mechanical properties of Mn modified, Ti-Nb-based alloys

• Published in: Journal of alloys and compounds Vol. 723; pp. 1091 - 1097
• Main Authors: Chen, Z., Liu, Y., Jiang, H., Liu, M., Wang, C.H., Cao, G.H.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.11.2017; Elsevier BV
• Subjects: Alloys; Ambient temperature; Beta phase; Biocompatibility; Biomedical materials; Crucibles; Ductility; Elastic modulus; Electron microscopy; Levitation melting; Manganese base alloys; Mechanical properties; Metals and alloys; Microstructure; Modulus of elasticity; Niobium; Phase transitions; Plastic deformation; Solid phases; Solution strengthening; Surgical implants; Tensile properties; Tensile strength; Titanium base alloys; Transmission electron microscopy; Mechanical properties; Elastic modulus; Metals and alloys; Transmission electron microscopy; Microstructure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2017.06.311

Ti-16Nb-xMn (x = 0, 1, 3, 5, 7, and 9 at.%) alloys were prepared by cold crucible levitation melting, and their tensile properties were studied at ambient temperature. The Ti-16Nb-7Mn alloy exhibited a high tensile strength of 695 MPa, large plastic strain of 43%, and low elastic modulus of 77 GPa. Transmission electron microscopy studies revealed that orthorhombic α″ and body-centered cubic β phases present in the Ti-16Nb alloy were modified by the addition of Mn to form a single β phase structure. The improvement in the mechanical properties with the addition of Mn is attributed to three factors: (1) the change of phase constitutions from α″+β to β+ω, then to β, (2) solid solution strengthening, and (3) increased stability of the β phase. The Ti-16Nb-7Mn alloy displayed high strength, high ductility, and low elastic modulus, making it a promising candidate for biomedical applications. [Display omitted] •Ti-16Nb-1Mn alloy (at.%) consisted of α″ and ω phases in addition to β phase.•Ti-16Nb-xMn (x = 7 and 9 at.%) alloys exhibited a single β phase structure.•Addition of 7 and 9 at.% Mn increased both strength and ductility of Ti-Nb alloys.•The Ti-16Nb-7Mn (at.%) alloy exhibited the lowest elastic modulus of 77 GPa.