title: Solute lean Ti-Nb-Fe alloys: An exploratory study.
abstract: In this study, we explored the Ti-Nb-Fe system to find an optimal cost-effective composition with the lowest elastic modulus and the lowest added Nb content. Six Ti-(31-4x)Nb-(1+0.5x)Fe ingots were prepared and Nb was substituted with Fe, starting at Ti-31Nb-1.0Fe and going up to Ti-11Nb-3.5Fe (wt%). The ingots were subjected to cold rolling, recrystallization and solution treatment, followed by water-quenching (WQ), furnace cooling (FC) or step-quenching to 350°C, which caused massive formation of isothermal ω phase. All the water-quenched alloys displayed athermal ω phase, which is apparently the result of fully collapsed β phase. The Fe content improved the compressive strength of the alloys. In the FC alloys, substitution with Fe favored the formation of α phase instead of ω phase, giving rise to a solute-rich β phase with a lattice parameter of 0.3249nm. Among the FC alloys, the lowest modulus of 83±4GPa was obtained in the Ti-19Nb-2.5Fe alloy, which exhibited fine and well dispersed α precipitation and absence of ω phase. DSC experiments indicated that the experimental alloys showed varying phase stability during heating.
authors: School of Mechanical Engineering, University of Campinas, Brazil.
authors: Camilo A F
authors: CAF
authors: Salvador
authors: School of Mechanical Engineering, University of Campinas, Brazil.
authors: Mariana R
authors: MR
authors: Dal Bó
authors: School of Mechanical Engineering, University of Campinas, Brazil.
authors: Fernando H
authors: FH
authors: Costa
authors: School of Mechanical Engineering, University of Campinas, Brazil.
authors: Marcia O
authors: MO
authors: Taipina
authors: School of Mechanical Engineering, University of Campinas, Brazil.
authors: Eder S N
authors: ESN
authors: Lopes
authors: School of Mechanical Engineering, University of Campinas, Brazil. Electronic address: caram@fem.unicamp.br.
authors: Rubens
authors: R
authors: Caram
mesh_terms: D000497:Alloys / Q000032:analysis*; D019245:Compressive Strength; D055119:Elastic Modulus; D006358:Hot Temperature; D007501:Iron / Q000032:analysis*; D008422:Materials Testing; D009556:Niobium / Q000032:analysis*; D014025:Titanium / Q000032:analysis*
chemical_list: D000497:Alloys; D009556:Niobium; D014025:Titanium; D007501:Iron
keywords: Alloy design; Mechanical properties; Phase transformations; Quenching; Titanium alloys