Microstructures, mechanical properties and cytotoxicity of low cost beta Ti-Mn alloys for biomedical applications.
The microstructures, mechanical properties and biocompatibility of low cost β-type Ti-(6-18)Mn alloys were investigated after solution treatment. Ti-9 Mn exhibits the best combination of tensile strength and elongation among the fabricated alloys, and its performance is comparable to or superior to those of Ti-6Al-4V ELI (Ti-64 ELI) in terms of every parameter evaluated. A hardness of 338 HV, a Young's modulus of 94 GPa, a 0.2% proof stress of 1023 MPa, an ultimate tensile strength of 1048 MPa and elongation of 19% were obtained for Ti-9 Mn. Furthermore, the cell viability and metallic ion release ratios are comparable to those of commercially pure titanium, making this alloy promising for biomedical applications. The Young's modulus is also lower than that of Ti-64 ELI (110 GPa), which can possibly reduce the stress shielding effect in implanted patients.


CONCLUSIONS
This study evaluates mechanical and biological performance of low cost solution treated β-type Ti-(6, 9, 13 and 18 mass%)Mn alloys. It includes alloys containing a Mn content range higher than most previously published works (which is around or lower than 8 mass%). Furthermore, the effects of the ω phase and the β phase stability of the alloys over some mechanical properties and microstructures are discussed. Ion release behavior under simulated body fluids and cell viability are also evaluated. For the case of the Ti-9 Mn, a mechanical and biological performance that is comparable to or superior than that of the widely used Ti-6Al-4V ELI and commercially pure Ti was observed.
Department of Metallurgy, Materials Science and Materials Processing, Tohoku University, 6-6 Aoba, Aramaki, Aoba-Ku, Sendai, Miyagi 980-8579, Japan.
Pedro Fernandes
PF
Santos
Tohoku University, Aoba-ku, Katahira 2-1-1, Institute for Materials Research, Building 2, Sendai, Miyagi 980-8577, Japan. Electronic address: niinomi@imr.tohoku.ac.jp.
Mitsuo
M
Niinomi
Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan.
Ken
K
Cho
Tohoku University, Aoba-ku, Katahira 2-1-1, Institute for Materials Research, Building 2, Sendai, Miyagi 980-8577, Japan.
Masaaki
M
Nakai
Tohoku University, Aoba-ku, Katahira 2-1-1, Institute for Materials Research, Building 2, Sendai, Miyagi 980-8577, Japan.
Huihong
H
Liu
Instrument Analysis Center, Kitami Institute of Technology, 165 Koen-Cho, Kitami, Hokkaido 090-8507, Japan.
Naofumi
N
Ohtsu
Instrument Analysis Center, Kitami Institute of Technology, 165 Koen-Cho, Kitami, Hokkaido 090-8507, Japan.
Mitsuhiro
M
Hirano
Faculty of Chemistry, Materials and Bioengineering, Kansai University, Suita 564-8680, Japan.
Masahiko
M
Ikeda
Graduate School of Engineering, Tohoku University, 6-6-02 Aza Aoba, Aramaki, Aoba-ku, Sendai, Miyagi 980-8579, Japan.
Takayuki
T
Narushima
D016475:3T3 Cells; D000497:Alloys / Q000737:chemistry / Q000633:toxicity; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001672:Biocompatible Materials / Q000737:chemistry / Q000633:toxicity; D002470:Cell Survival / Q000187:drug effects*; D019245:Compressive Strength; D055119:Elastic Modulus; D006244:Hardness; D008345:Manganese / Q000737:chemistry* / Q000633:toxicity*; D008422:Materials Testing; D051379:Mice; D013314:Stress, Mechanical; D013499:Surface Properties; D013718:Tensile Strength; D014025:Titanium / Q000737:chemistry* / Q000633:toxicity*
D000497:Alloys; D001672:Biocompatible Materials; D008345:Manganese; D014025:Titanium
Biocompatibility; Low cost Ti alloy; Mechanical properties; Ti–Mn alloys; β phase