• Title/Summary/Keyword: Ti-6Al-4V alloy

Search Result 314, Processing Time 0.04 seconds

Ion release and Biocompatibility of Ti-6Al-4V Alloys for Dental application

  • Kang, Jung-In;Son, Mee-Kyoung;Choe, Han-Cheol
    • Proceedings of the Korean Institute of Surface Engineering Conference
    • /
    • 2015.11a
    • /
    • pp.303-303
    • /
    • 2015
  • In order to investigate ion release and biocompatibility of Ti-6Al-4V dental alloy by electrochemical corrosion test and MTT assay, commercial Ti-6Al-4V alloy rod (99.99% Ti, USA, Co) were used in the study. The microstructure of the alloys was examined by optical microscopy (OM), Field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), MTT assay, and corrosion test. From the polarization curves, very low current densities were obtained for Ti-6Al-4V alloys, indicating a formation of stable passive layer.

  • PDF

A Study on Microstructure and Mechanical Properties of Hf, Ta Added Ti-l5Sn-4Nb system Alloys for Biomaterial (Hf, Ta가 첨가된 Ti-l5Sn-4Nb계 생체용 합금의 미세조직 및 기계적 성질에 관한 연구)

  • 김대환;이경구;박효병;이도재
    • Journal of the Korean institute of surface engineering
    • /
    • v.33 no.4
    • /
    • pp.251-260
    • /
    • 2000
  • Ta and Hf added Ti-l5Sn-4Nb alloys without V and Al elements for biomaterial were melted by arc furnace in response to recent concerns about the long term safety of Ti-6Al-4V alloy. All specimens were homogenized at $1000^{\circ}C$ and solution treatment was performed at $812^{\circ}C$ and aging treatment at $500^{\circ}C$. The microstructure and mechanical properties were analysed by optical micrograph, hardness tester and instron. Ti-l5Sn-4Nb system alloys showed widmanstatten microstructure which is typical microstructure in $\alpha$$\beta$ type Ti alloys. The Ti-l5Sn-4Nb-2Hf and Ti-l5Sn-4Nb-2Ta alloys showed better hardness and tensile strength compared with Ti-6Al-4V. The result of XPS analysis, Ti-l5Sn-4Nb alloy in air atmosphere consisted of $TiO_2$, SnO and NbO.

  • PDF

The Evaluation of Mechanical Properties on the Changes of Microstructure for Titanium Alloy (Ti-6Al-4V) (티타늄 합금(Ti-6Al-4V)의 조직변화에 따른 기계적 특성 평가)

  • Gwon, Jae-Do;Bae, Yong-Tak;Choe, Seong-Jong
    • Transactions of the Korean Society of Mechanical Engineers A
    • /
    • v.26 no.4
    • /
    • pp.609-616
    • /
    • 2002
  • The characteristics of mechanical behavior are investigated for Ti-6Al-4V alloy. Four kinds of the specimens are prepared under different heat treatments in order to produce different microstructures. In the present investigations, impact, tensile and fatigue crack growth tests are performed for each test specimen. The results obtained through the investigations are compared. Additionally fr actal dimensions of crack pass are obtained using the box counting method. The results are, 1) the microstructures shows as equiaxed, bimodal and Widmanstatten microstructures respectively, 2) the impact energy and elongation are superior fur the bimodal microstructure, and the hardness and tensile strength are superior fur the Widmanstatten microstructure, 3) the fatigue crack growth rate is similar to all microstructures in low ΔK region while that of equiaxed microstructure is the largest, and that of Widmanstatten microstructure is the lowest in high ΔK region respectively, 4) the fractal dimension D of Widmanstatten microstructure shows higher value than that of the equiaxed and bimodal microstructures under 200 magnification view of the SEM micrographs.

Flow Stress Determination of Johnson-Cook Model of Ti-6Al-4V Material using 3D Printing Technique (3D 프린팅으로 제작한 Ti-6Al-4V 재료의 Johnson-Cook 모델의 유동 응력 결정)

  • Park, Dae-Gyoun;Kim, Tae-Ho;Jeon, Eon-Chan
    • Journal of the Korean Society of Manufacturing Process Engineers
    • /
    • v.17 no.4
    • /
    • pp.64-69
    • /
    • 2018
  • This paper investigates the compressive deformation behavior of direct metal tooling (DMT), processing titanium alloy (Ti-6Al-4V) parts under high strain loading conditions. Split Hopkinson Pressure Bar (SHPB) experiments were performed to determine the flow stress and the coefficients of the Johnson-Cook model. This model is described as a function of strain, strain rate, and temperature. SHPB experiments were performed to characterize the deformation behavior of specimens made with 3D printers, using Ti-6Al-4V material under high temperature and dynamic loading.

Hot Forging Process of High Strength Ti-6Al-4V Bolt (Ti-6Al-4V 고강도 볼트 성형 기술 개발)

  • Kim, Jeoung-Han;Lee, Chae-Hoon;Hong, Jae-Keun;Kim, Jae-Ho;Yeom, Jong-Taek
    • Proceedings of the Korean Society for Technology of Plasticity Conference
    • /
    • 2008.10a
    • /
    • pp.87-90
    • /
    • 2008
  • Since fastener bolt for airplane require high specific strength and corrosion resistance, Ti-6Al-4V alloy is widely used. However, the Ti-6Al-4V bolt is generally manufactured by cutting and rolling because of their poor workability. The aim of present work is to develop hot forming technology for high strength Ti-6Al-4V. Various heat-treatments were applied to specimen in order to increase hot-workability and prevent galling with die Multiple forging were simulated with FE code to determine optimum process parameters including specimen temperature, strain rate, local strain, and thermal shrinkage. Forged samples were heat-treated again to increase their mechanical properties.

  • PDF

Effect of Thermal Oxidation Coating on the Hot Forging Process of High Strength Ti-6Al-4V Bolt (Ti-6Al-4V 고강도 볼트의 성형성에 미치는 표면산화효과)

  • Kim, Jeoung-Han;Lee, Chae-Hoon;Hong, Jae-Keun;Kim, Jae-Ho;Yeom, Jong-Taek
    • Transactions of Materials Processing
    • /
    • v.18 no.3
    • /
    • pp.251-255
    • /
    • 2009
  • Since fastener bolt for airplane require high specific strength and corrosion resistance, Ti-6Al-4V alloy is widely used. However, the Ti-6Al-4V bolt is generally manufactured by cutting and rolling because of their poor workability. The aim of present work is to develop hot forming technology for high strength Ti-6Al-4V. Various heat-treatments were applied to specimen in order to increase hot-workability and prevent galling with die. Multiple forging were simulated with FE code to determine optimum process parameters including specimen temperature, strain rate, local strain, and thermal shrinkage. Forged samples were heat-treated again to increase their mechanical properties.

Effect of Dry-Electropolishing on the High Cycle Fatigue Properties of Ti-6Al-4V Alloy Manufactured by Selective Laser Melting (선택적 레이저 용융법으로 제조된 Ti-6Al-4V 합금의 고 주기 피로 특성에 미치는 건식 전해 연마의 영향)

  • Yang, Dong-Hoon;Kim, Young-Kyun;Hwang, Yujin;Kim, Myoung-Se;Lee, Kee-Ahn
    • Journal of Powder Materials
    • /
    • v.26 no.6
    • /
    • pp.471-476
    • /
    • 2019
  • Additively manufactured metallic components contain high surface roughness values, which lead to unsatisfactory high cycle fatigue resistance. In this study, high cycle fatigue properties of selective laser melted Ti-6Al-4V alloy are investigated and the effect of dry-electropolishing, which does not cause weight loss, on the fatigue resistance is also examined. To reduce the internal defect in the as-built Ti-6Al-4V, first, hot isostatic pressing (HIP) is conducted. Then, to improve the mechanical properties, solution treatment and aging are also implemented. Selective laser melting (SLM)-built Ti64 shows a primary α and secondary α+β lamellar structure. The sizes of secondary α and β are approximately 2 ㎛ and 100 nm, respectively. On the other hand, surface roughness Ra values of before and after dry-electropolishing are 6.21 ㎛ and 3.15 ㎛, respectively. This means that dry-electropolishing is effective in decreasing the surface roughness of selective laser melted Ti-6Al-4V alloy. The comparison of high cycle fatigue properties between before and after dry-electropolished samples shows that reduced surface roughness improves the fatigue limit from 150 MPa to 170 MPa. Correlations between surface roughness and high cycle fatigue properties are also discussed based on these findings.

Effects on Tensile Strength of Base and Weld Metal of Ti-6Al-4V Alloy in Short Time Exposure to High Temperature (Ti-6Al-4V 합금의 단시간 고온 노출 시 모재 및 용접부의 인장강도 특성)

  • Chae, Byoung-Chan
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.17 no.4
    • /
    • pp.413-421
    • /
    • 2014
  • Since the structural temperature of a flight vehicle flying at high speed rises rapidly due to aerodynamic heating, it is necessary for optimum structural design to obtain proper material properties at high temperature by taking into account of its operational environment. For a special alloy, analysis data on strength change due to exposure time to high temperature are very limited, and most of them are for an exposure time longer than 30 minutes for long term operations. In this study, base and weld metal samples of Ti-6Al-4V alloy had been prepared and high temperature tensile tests with induction heating were performed, and then high temperature strength characteristics and strength recovery characteristics through cooling have been analyzed. Pre-tests to determine maximum heating rate were performed, and response characteristics for temperature control were confirmed. As a result, high temperature tensile strength appeared to be lower than that of room temperature, but it was higher than that of high temperature of 30 minite exposure listed in MMPDS. In strength recovery through cooling Ti-6Al-4V alloy has shown higher recovery rate compared with other alloys.