• The Journal of Korean Academy of Prosthodontics
• /
• v.36 no.5
• /
• pp.701-720
• /
• 1998

Research advances in dental implantology have led to the development of several different types of materials and it is anticipated that continued research will lead to advanced dental implant materials. Currently used pure titanium has relatively low hardness and strength which may limit its ability to resist functional loads as a dental implant. Ti-6Al-4V also has potential problems such as corrosion resistance. osseointegration properties and neurologic disorder due to aluminium and vanadium, known as highly toxic elements, contained in Ti-6Al-4V. Newly developed titanium based alloys(Ti-20Zr-3Nb-3Ta-0.2Pd-1In, Ti-20Zr-3Nb-3Ta-0.2Pd) which do not contain toxic metallic components were designed by the Korea Institute of Science and Technology (KIST) with alloy design techniques using Zr, Nb, Ta, Pd, and In which are known as non-toxic elements. Biocompatibility and osseointegration properties of these newly designed alloys were evaluated after implantation in rabbit femur for 3 months. The conclusions were as follows : 1. Mechanical properties of the new designed Ti based alloys(Ti-20Zr-3Nb-3Ta-0.2Pd-1In, Ti-20Zr-3Nb-3Ta-0.2Pd) demonstrated close hardness and tensile strength values to Ti-6Al-4V. 2. New desinged experimental alloys showed stable corrosion resistance similar to the pure Ti but better than Ti-6Al-4V. However, the corrosion rate was higher for the new alloys. 3. Cell culture test showed that the new alloys have similar cell response compared with pure Ti and Ti-6Al-4V with no cell adverse reaction. 4. New designed alloys showed similar bone-metal contact ratio and osseointegration properties compared to pure Ti and Ti-6Al-4V after 3 months implantation in rabbit femur. 5. Four different surface treatments of the metals did not show any statistical difference of the cell growth and bone-metal contact ratio.

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2014.11a
• /
• pp.185-185
• /
• 2014

In this study, we investigated surface characteristics of hydroxyapatite coated surface on nano/micro pore structured Ti-35Ta-xNb alloys. This paper was focus on morphology and corrosion resistance of Anodic oxidation. To prepare the samples, Ti-35Ta-xNb (x= 0, 10 wt. %) alloys were manufactured by arc melting and heat-treated for 12 h at $1050^{\circ}C$ in Ar atmosphere at $0^{\circ}C$ water quenching. Micro-pore structured surface was performed using anodization with a DC power supply at 280 V for 3 min, nanotube formed on Ti-35Ta-xNb alloys was performed using DC power supply at 30 V in 60 min at room temperature. Surface morphology and structure were examined by field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2000.11a
• /
• pp.166-166
• /
• 2000

• Proceedings of the Korean Institute of Surface Engineering Conference
• /
• 2012.05a
• /
• pp.254-254
• /
• 2012

The purposed of this work was to determine surface charateristics of anodized Ti-30Nb-xTa alloys with Ta content. Samples were prepared by arc melting, followed by followed by homogenization for 12 hr at $1000^{\circ}C$ in argon atmosphere. The electrolyte for anodization treatment was prepared by mixing 465ml $H_2O$ with 35M $H_3PO_4$ and anodized at 180V to 220V. The microstructures of the alloys were examined by X-ray diffractometer (XRD) and optical microscopy (OM). Surface characteristics of anodized Ti-30Nb-xTa alloys was investigated by potentiodynamic test and potentiostatic in 0.9% Nacl solution at $36.5{\pm}1^{\circ}C$. It was observed that the changed ${\alpha}$ phase to ${\beta}$ phase with Ta content.

• Korean Journal of Materials Research
• /
• v.17 no.1
• /
• pp.6-10
• /
• 2007

In the present study, we investigated the formation of self-organized nanostructure oxide layers on CP Ti and Ti-10Ta-10Nb alloy in an electrolyte of 1M phosphoric acid and 1.5 wt% Hydrofluoric acid. The morphology of oxide film on substrate was observed using scanning electron microscopy and transmission electron microscopy The surface roughness of titanium oxide film was analyzed by atomic force microscopy and the crystalline of specimen was investigated using X-ray diffractometer. The results of this study showed that well-aligned titanium oxide nanotubes are formed with diameter of approx. 100nm and length of approx. 500nm with CP Ti. However, it is clear that TiTaNb alloy highly irregular structure with various diameters. Transmission electron microscope investigations show that the specimens were confirmed as amorphous. Such titanium oxide nanotubes are expected a well-adhered bioacitive surface layer on titanium substrate for orthopedics and dental implants.

• Journal of the Korean Society for Heat Treatment
• /
• v.18 no.2
• /
• pp.91-98
• /
• 2005

Both commercially pure titanium and Ti-6Al-4V alloy have been widely used as biomaterials because of their excellent biocompatibility, corrosion resistance and mechanical properties. However, in recent years, vanadium has been found to cause cytotoxic effects and adverse tissue reactions, while aluminium has been associated with potential neurological disorders. A newly designed ${\alpha}+{\beta}$ type Ti alloy, Ti-10Ta-10Nb alloy showed superior properties to CP Ti and Ti-6Al-4V alloy in the point of biomaterial, and elucidated the future uses as a biomaterial. Microstructural changes of Ti-10Ta-10Nb alloy after hot-rolling, warm-rolling, solution and aging treatment were investigated. According to TEM results, the microstructures after solution treatment were composed of mostly ${\alpha}$ phase with a trace of ${\beta}$ phase due to adding ${\beta}$-phase stabilizer tantalum and niobium. The microstructures after warm-rolling is coarse and elongated ${\alpha}$ phase and hot rolling resulted in very fine ${\alpha}$ widmanst$\ddot{a}$tten. The highest value of hardness was obtained by aging treatment at $400^{\circ}C$ for 20hr in which microstructure consisted of very fine ${\alpha}$ phase in ${\beta}$ matrix.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.792-795
• /
• 2002

In previous researches, it is reported that Ti-10Ta-10Nb is robuster than Ti-6A1-4V which is used as a biomaterial in a experiment of cytotoxicity. Ti-10Ta-10Nb has enough hardness to be required as a biomaterial because the change of its hardness can be controlled more than 100% according to heat treatment condition and manufacturing condition. There are many hardness changing condition including Cast Homogenization, Solution treatment. Forging, Rolling in this research. The changing form and amount of new Ti-10Ta-10Nb to be developed in this researches, are measured as quantitative. Specially, the changing hardness amount of the specimen that is manufactured in single phase temperature, i.e. 80$0^{\circ}C$, are measured in case of high temperature rolling and high temperature cast condition.

• Mineral and Industry
• /
• v.27
• /
• pp.24-34
• /
• 2014

• Proceedings of the IEEK Conference
• /
• 2006.06a
• /
• pp.985-986
• /
• 2006

The epitaxial $KTa_{0.524}Nb_{0.446}Ti_{0.03}O_3$ films with 3% Ti were investigated. Titanium (+4) substitution on the Nb/Ta site should reduce dielectric losses of KTN: Ti film by introducing an acceptor state. This acceptor state traps electrons due to oxygen vacancies that form during oxide film growth. KTN:Ti films were grown using pulsed laser deposition, and then annealed at different temperatures in oxygen ambient. The crystallinity, and surface morphology of KTN:Ti film were investigated using x-ray diffraction, and atomic force microscopy. The dielectric properties of Ti doped KTN films measured for unannealed and annealed films will be reported. Tunability and dielectric loss of as-deposited KTN:Ti film were determined to be 10% and 0.0134, respectively. For films annealed at $800^{\circ}C$ and $900^{\circ}C$, the dielectric loss decreased but with a decrease in tunability as well.

• Proceedings of the Korea Association of Crystal Growth Conference
• /
• 1997.06a
• /
• pp.49-51
• /
• 1997

New complex perovskite compounds (Na0.5Sr0.5)(Ti0.5Nb0.5)O3, (Na0.5Sr0.5)(Zr0.5Ti0.5)O3 and (Na0.5Sr0.5)(Ti0.5Ta0.5)O3 have been prepared. The crystal structures of these compounds were determined by powder X-ray Rietveld analysis. The crystal structure of (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 and (Na0.5Sr0.5)(Zr0.5Ta0.5)O3 was Pmmn, and that of (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 was I4/mmm. All these compounds showed the superstructure due to the oxygen octahedron distortion. The selected bond distances and bond angles were calculated by the OFFER. The octahedron distortion for each sample, which was measured from the bond distances and bond angles, showed the following order: (Na0.5Sr0.5)(Z0.5Ta0.5)O3> (Na0.5Sr0.5)(Ti0.5Nb0.5)O3 > (Na0.5Sr0.5)(Ti0.5Ta0.5)O3. Dielectric properties were measured for the samples. In this study, the crystal structure and dielectric properties of the new complex perovskite structures and discussed.