• 제목/요약/키워드: Pure Ti

검색결과 597건 처리시간 0.027초

생체용 Ti-15Sn계 합금의 내식성 및 기계적 성질에 관한 연구 (A Study on Corrosion Resistance and Mechanical Properties of Ti-15Sn System Alloys for Medical Implants)

  • 이도재;김대환;박효병;이경구
    • 한국주조공학회지
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    • 제20권3호
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    • pp.208-215
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    • 2000
  • The mechanical properties and corrosion resistance of Ti alloys for medical implants have been investigated. Ti, Ti-15Sn-4Nb and Ti-15Sn-4Nb-2Zr alloys were melted in arc furnace and the corrosion resistance of Ti alloys was evaluated by anodic polarization test. The microstructure and mechanical properties of Ti alloys were analysed by optical microscope, hardness and tensile tester. The tensile strength of the pure-Ti improved by addition of Sn and Nb and Ti-15Sn-4Nb alloy showed better Rockwell hardness compared with pure Ti. However, there was no significant difference in corrosion resistance between thoseTi-alloys made of Pure-Ti and Ti-15Sn-4Nb alloy. The passive films on the Ti-15Sn-4Nb alloy in air atmosphere consisted of $TiO_2$, SnO and NbO as demonstrated by X-ray photoelectron spectroscopy(XPS)

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침전법으로 TiCl4 수용액의 산농도 조절을 통한 나노크기의 순수한 브루카이트상 이산화티타늄 분말 제조 (Synthesis of Pure Brookite-type TiO2 Nanoparticles from Aqueous TiCl4 Solution with controlled Acidity by Precipitation Method)

  • 이정훈;양영석
    • 공업화학
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    • 제18권6호
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    • pp.545-551
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    • 2007
  • $TiCl_4$ 수용액의 침전반응으로 $TiO_2$를 제조할 때 침전용액의 염산농도와 반응온도 및 $Ti^{4+}$농도는 $TiO_2$ 침전물의 결정구조를 결정하는 중요한 인자이며, 이들의 조절을 통하여 브루카이트상의 부피분율 제어가 가능하다. 순수한 브루카이트상 이산화티타늄을 제조하기 위해서는 $Ti^{4+}$농도를 1.0 M 이하로 유지하고, 침전용액의 염산농도를 2.53~6.41 M이 되도록 조절한후 $70^{\circ}C$ 이하에서 20 h 침전반응 시켜야 한다. 한편, 순수한 브루카이트상 분말을 열처리한 결과 브루카이트상은 열처리 온도의 증가에 따라 아나타제상으로 상전이 된 후 최종적으로 루틸상으로 상변화가 진행되었다.

수열합성법으로 제조된 Zn-$TiO_2$ 나노입자와 $TiO_2$ 나노입자가 zebrafish 배발생에 미치는 영향 (The Effect of Nano-scale Zn-$TiO_2$ and Pure $TiO_2$ Particles were Prepared using a Hydrothermal Method on Zebrafish Embryogenesis)

  • 여민경;김효은
    • Environmental Analysis Health and Toxicology
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    • 제24권4호
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    • pp.333-339
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    • 2009
  • In this study, we investigated the biological toxicity of nano-scale Zn (0.1, 0.5, and 1 mol%)-doped $TiO_2$ and pure $TiO_2$ nanoparticles using zebrafish embryogenesis as our model organism. Zn-doped $TiO_2$ nanoparticles were prepared using a conventional hydrothermal method for the insertion of zinc into the $TiO_2$ framework. The characters of Zn-doped $TiO_2$ (0.1%, 0.5%, 1%Zn) and pure $TiO_2$ were about 7~8 nm. These sizes were smaller than 100~200 nm of $TiO_2$ was prepared using the sol-gel method. Particularly, in this study, we found no significant biological toxicity in the hatching rate and abnormal rate under expose pure $TiO_2$ and Zn-doped $TiO_2$ nanoparticles were prepared using a conventional hydrothermal method of zebrafish. It was different from the biological damage under $TiO_2$ nanoparticles were prepared using sol-gel method. We assessed that the damage was not linked to the particle's nanometer size, but rather due to the prepare method. Moreover, $TiO_2$ nanoparticles were prepared using a hydrothermal method were not shown to cause cytotoxic effects, like apoptosis and necrosis, that are the major markers of toxicity in organisms exposed to nanomaterials. Therefore, there is some relationship with biological toxicity of nanoparticles and the prepare method of nanometer size particles.

가토의 경골에 이식된 새로운 티타늄계 합금 주위의 골형성에 관한 형태학적 연구 (A HISTOMORPHOMETRIC STUDY OF BONE APPOSITION TO NEWLY DEVELOPED TI-BASED ALLOYS IN RABBIT BONE)

  • 김태인
    • 대한치과보철학회지
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    • 제36권5호
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    • pp.701-720
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    • 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.

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순수 타이타늄 기반 산화물분산강화 합금의 미세조직 및 기계적 특성 (Microstructure and Mechanical Properties of Oxide Dispersion Strengthened alloy Based on Commercially Pure Titanium)

  • 박태성;김정한
    • 한국분말재료학회지
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    • 제25권4호
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    • pp.327-330
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    • 2018
  • This study is conducted as a preliminary research to verify the feasibility of Ti-based Oxide dispersion strengthened (ODS) alloy. Pure-Ti powder is mixed with $Y_2O_3$ powder and subsequently, mechanically alloyed at $-150^{\circ}C$. The Ti-based ODS powder is hot-isostatically pressed and subsequently hot-rolled for recrystallization. The microstructure consists of elongated grains and Y excess fine particles. The oxide particle size is larger than that of the typical Fe-based ODS steel. Tensile test shows that the tensile ductility is approximately 25%, while the strength is significantly higher than that of pure Ti. The high-temperature hardness of the Ti-ODS alloy is also significantly higher than that of pure Ti at all temperatures, while being lower than that of Ti-6Al-4V. The dimple structure is well developed, and no evidence of cleavage fracture surface is observed in the fracture surface of the tensile specimen.

순 Ti의 고온 가스질화에 따른 미세조직 변화 (Phase Changes of Pure Ti During High Temperature Gas Nitriding)

  • 이해정;공정현;배진범;서종환;김영희;성장현
    • 열처리공학회지
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    • 제22권2호
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    • pp.88-94
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    • 2009
  • The effect of high temperature gas nitrding (HTGN) on the surface microstructure in pure Ti was investigated. Two phases of TiN and $Ti_2N$ appeared at the outmost surface, and the wide ${\alpha}$-Ti layer was formed at the next layer. On the other hand, the interior region, where the nitrogen was not permeated, exhibited ${\alpha}$'phase. The outmost surface of TiN and $Ti_2N$ showed the maximum hardness of 1000Hv, while the interior ${\alpha}$'phase was ${\sim}350$ Hv. The permeation depth of nitrogen increased with increasing the gas nitriding temperature and time. The nitrogen concentration of the surface layer seems to be over 12.7% at $1100^{\circ}C$.

질소를 도핑한 TiO2를 이용한 부식산 분해 (Degradation of Humic Acid Using N-Doped TiO2)

  • 소지양;이동석
    • 산업기술연구
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    • 제31권B호
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    • pp.119-125
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    • 2011
  • N-doped Titanium oxides were prepared by using urea as a source of nitrogen. The photoactivities of the doped $TiO_2$ were evaluated on the basis of degradation of humic acid in aqueous solutions with different light sources, ultraviolet lamp, fluorescent lamp and solar light. XRD analysis was conducted to identify the crystal structure of the synthesized photocatalysts. N-doped $TiO_2$ and $pure-TiO_2$ was anatase type. SEM results showed that spherical particles were formed, which are the characteristics of the anatase form. N doped $TiO_2$ showed higher $UV_{254}$ decrease ratio and DOC removal ratio compared to $pure-TiO_2$. The humic acid degradation reaction using the UV-A lamp and UV-C lamp was assigned to pseudo-first order reaction. For solar light, only $pure-TiO_2$ and $N-TiO_2$ exhibited the pseudo-first order reaction.

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물-$TiO_2$ 나노유체 풀비등에서의 임계열유속 (Critical heat flux behavior in pool boiling of $water-TiO_2$ nanofluids)

  • 김형대;김무환
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.1470-1474
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    • 2004
  • 'Nanofluids' means suspension of common fluids with particles of the order of nanometers in size. The present research is an experimental study of critical heat flux (CHF) behavior in pool boiling of $water-TiO_2$ nanofluids under atmospheric pressure. CHF for pure water and $water-TiO_2$ nanofluids were respectively measured using disk-type copper block heater with 10mm diameter, and CHF of water with surfactant was also measured to consider the effect of surfactant used to disperse nanoparticle. The results show a large increase in CHF for $water-TiO_2$ nanofluids compared to pure water. After CHF occurred, heat flux in pool boiling for $water-TiO_2$ nanofluids was maintained in considerable value, but not for pure water.

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기상 가수분해에 의한 순수 $TiO_2$ 초미립자의 제조 (Preparation of $TiO_2$ Pure Nanoparticles by Vapor-Phase Hydrolysis)

  • 이수근
    • 한국포장학회지
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    • 제9권1호
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    • pp.11-18
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    • 2003
  • The pure $TiO_2$ particles have been prepared in vapor-phase hydrolysis of titanium tetraisopropoxide(TTIP). The rate of TTIP hydrolysis was so fast that the overall rate of formation of $TiO_2$ was controlled by the rate of mixing of TTIP and $H_2O$. Thus, the primary $TiO_2$ particles were prepared in nano sizes to form chainlike aggregates due to rapid coagulation. The pure $TiO_2$ particles as prepared were amorphous at the reactor set temperatures below $400^{\circ}C$ and became anatase at the temperatures of $450^{\circ}C$ above while the weak rutile peaks were also observed above $800^{\circ}C$. The actual size of primary particles as prepared were reduced by increasing the reactor set temperature while their crystalline sizes as well as BET sizes increased by post-sintering.

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Ti-Ni합금에 생성하는 나노튜브 산화막의 형태 및 성장거동

  • 김민수;한동원;권아람;나찬웅
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2017년도 춘계학술대회 논문집
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    • pp.133-133
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    • 2017
  • [서론] Pure Ti 및 Ti합금의 양극산화법에 의해 만들 수 있는 자기조직화된 나노튜브피막은 광촉매, 태양전지 등 다양한 분야에서 많은 연구가 되고 있다. 양극산화법에 의해 생성되는 산화피막층의 성장거동에 대해서 지금까지 용액의 pH, 온도 및 인가전압 등 양극산화조건의 영향에 대해 많은 연구가 보고 되었다. 하지만, 양극산화에 사용되는 기판의 특성에 대해서는 많은 연구가 이루어지지 않고 있다. 본 연구에서는 pure Ti 및 Ti-Ni합금에 양극산화법에 의해 생성하는 나노튜브 피막층의 성장거동에 대해 기판의 특성(Ni농도 변화 및 phase변화)이 피막층의 형태 및 성장거동에 미치는 영향에 대해서 조사 하였다. [실험방법] Sample은 pure Ti 및 Ti-xNi(x=49.0, 51.1, 52.2, 52.5 at.%)를 이용하였다. Ti-Ni합금은 아크용해로 제작 후 $1000^{\circ}C$ 에서 24시간 균질화 처리 후 20% 냉간압연을 하였다. 합금의 조성 및 결정구조 분석은 EPMA 및 XRD를 통해 조사 하였고, 양극산화는 미량의 물 및 불화암모늄을 포함한 에틸렌글리콜 용액에서 20, 35, 50V 20분간 실시하였다. 양극산화법에 의해 형성한 산화피막층은 FE-SEM 및 TEM을 통해 관찰 하였다. [결론] Pure Ti의 경우 모든 조건에서 나노튜브형태의 산화막이 형성되는 것을 알 수 있었다. 하지만, Ti-Ni 합금의 경우 20V, 35V에서는 sponge 형태의 산화막이 형성되고, 50V에서만 나노튜브형태의 산화막이 형성 되었다. 또한, 모든 시편에서 양극산화 시간이 증가함에 따라 나노튜브형태의 산화막은 sponge 형태로 구조적 변화가 일어나는 것을 알 수 있었다. 그리고, 기판 Ni농도가 증가 함에 따라 형성되는 산화막의 형태 변화는 가속화 되는 것을 알 수 있었다. 이러한 결과는 양극산화 초기 Ti의 우선적 산화에 의해 Ti과잉의 나노튜브층이 생성되고, 동시에 산화막과 합금계면에 Ni과잉층이 형성되는 것을 알 수 있었다. 산화막과 합금계면에 생성된 Ni과잉층에 의해 양극산화 시간이 증가함에 따라 sponge형태의 산화막이 생성되는 것을 알 수 있었다.

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