title: Bending springback behavior related to deformation-induced phase transformations in Ti-12Cr and Ti-29Nb-13Ta-4.6Zr alloys for spinal fixation applications.
abstract: The springback behavior of Ti-12Cr and Ti-29Nb-13Ta-4.6Zr (TNTZ) during deformation by bending was investigated; and the microstructures of the non-deformed and deformed parts of both alloys were systematically examined to clarify the relationship between microstructure and springback behavior. For the deformed Ti-12Cr alloy, deformation-induced ω-phase transformation occurs in both the areas of compression and tension within the deformed part, which increases the Young׳s modulus. With the deformed TNTZ alloy, deformation-induced ω-phase transformation is observed in the area of compression within the deformed part; while a deformation-induced α″ martensite transformation occurs in the area under tension, which is likely to be associated with the pseudoelasticity of TNTZ. Among these two alloys, Ti-12Cr exhibits a smaller springback and a much greater bending strength when compared with TNTZ; making Ti-12Cr the more advantageous for spinal fixation applications.
authors.affiliation: Department of Materials Science, Graduate School of Engineering, Tohoku University, 6-6 Aoba, Aramaki, Aoba-Ku, Sendai 980-8579, Japan.
authors.forename: Huihong
authors.initials: H
authors.lastname: Liu
authors.affiliation: Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan. Electronic address: niinomi@imr.tohoku.ac.jp.
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Niinomi
authors.affiliation: Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
authors.forename: Masaaki
authors.initials: M
authors.lastname: Nakai
authors.affiliation: Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Hieda
authors.affiliation: Institute for Materials Research, Tohoku University, Sendai 980-8577, Japan.
authors.forename: Ken
authors.initials: K
authors.lastname: Cho
mesh_terms: D000497:Alloys / Q000737:chemistry*; D002857:Chromium / Q000737:chemistry*; D019245:Compressive Strength; D055119:Elastic Modulus; D008422:Materials Testing; D009556:Niobium / Q000737:chemistry*; D044367:Phase Transition; D013131:Spine / Q000601:surgery*; D013314:Stress, Mechanical; D053831:Surgical Fixation Devices; D013635:Tantalum / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
chemical_list: D000497:Alloys; C481486:Ti-29Nb-13Ta-4.6Zr alloy; D009556:Niobium; D002857:Chromium; D013635:Tantalum; D015040:Zirconium; D014025:Titanium