DOI QR코드

DOI QR Code

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

  • Published : 2002.04.01

Abstract

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.

Keywords

References

  1. Imam M. A., Fraker A. C., Harris J. S. and Gilmore C. M., 1981, 'Influence of Heat Treatment on the Fatigue Lives of Ti-6Al-4V and Ti-4.5Al-5Mo-1.5Cr,' ASTM STP 796, pp. 105-119
  2. Brunski J. B., Moccia A. F., Jr., Pollack S. R., Korostoff E. and Trachtenberg D., 1981, 'Investigation of Surface of Retrieved End Osseous Dental Implants of Commercially Pure Titanium,' ASTM STP 796, pp. 189-205
  3. Fraker A. C., Ruff W., Sung P., Van Orden A. C. and Speck K. M., 1981, 'Surface Propagation and Corrosion Behavior of Titanium Alloys for Surgical Implants,' ASTM STP 796, pp. 206-219
  4. Smelaser R. E., Swedlow J. L. and Williams J. C., 1977, 'Analysis of Local Stresses and Strains in Ti-6Al-4V Widmanstatten ${\alpha}+{\beta}$ Microstructures,' ASTM STP 651, pp. 200-245
  5. Peters M., Gysler A. and Lu tjering G., 1984, 'Influence of Texture on Fatigue Properties of Ti-6Al-4V', Metall. Trans., Vol. 15A, pp. 1597-1605 https://doi.org/10.1007/BF02657799
  6. Imam M. A. and Gilmore C. M., 1983, 'Fatigue and Microstructural Properties of Quenched Ti-6Al-4V,' Metall. Trans., Vol. 14A, pp. 233-240 https://doi.org/10.1007/BF02651620
  7. Nakasa K., Hortita M. and Liu J., 1991, 'Fatigue Crack Initiation and Propagation in Ti-6Al-4V Alloy under Hydrogen Charging,' Trans. JSME A, Vol. 57, No. 522, pp. 25-31 (in Japanese)
  8. Dogan B. and Schwalbe K. H., 1997, 'Fracture Toughness Testing of TiAl Base Intermetallic Alloys,' Engineering Fracture Mechanics, Vol. 56, No. 2, pp. 155-165 https://doi.org/10.1016/S0013-7944(96)00114-2
  9. Yongqing Fu, Nee Lam Loh, Andrew W. Batchelor, Daoxin Liu, Xiaodong Zhu, Jaiwen He and Kewei Xu, 1998, 'Improvement in Fretting Wear and Fatigue Resistance of Ti-6Al-4V by Application of Several Surface Treatment and Coatings,' Surface and Coatings Technology, Vol.106, pp. 193-197 https://doi.org/10.1016/S0257-8972(98)00528-3
  10. Kinya Ogawa and Takhi Nojima, 1988, 'Impact Strength of Titanium Alloys,' J. Soc. Mat. Sci. Japan, Vol. 37, No. 421, pp. 1171-1177. (in Japanese) https://doi.org/10.2472/jsms.37.1171
  11. 서동이, 한전진, 1990, 'Ti-6Al-4V 합금의 가공 열처리에 따른 조직 및 피로특성변화에 관한 연구,' 대한금속학회지, Vol. 28, No. 1, pp. 23-31
  12. 강형구, 조현기, 1992, 'Ti-6Al-4V 합금에 있어서 용체화처리 및 냉각조건에 따른 상의 미시조직변화,' 대한금속학회지. Vol. 30, No. 11, pp. 1326-1333
  13. Charkaluk E., Bigerelle M. and Iost A., 1998, 'Fractals and Fracture,' Engineering Fracture Mechanics, Vol. 61, pp. 119-139 https://doi.org/10.1016/S0013-7944(98)00035-6
  14. Saburo Matsuoka, Hdieshi Sumiyoshi and Keisuke Ishikawa, 1990, 'Fractal Character of Scanning Tunneling Microscopic Images of Brittle Fracture Surfaces on Chromium,' Trans. JSME A, Vol. 56, No. 530, pp. 47-53. (in Japanese) https://doi.org/10.1299/kikaia.56.2091
  15. Amthony W. Thompson, 1999, 'Relations Between Microstructure and Fatigue Properties of Alpha-Beta Titanium Alloys,' in Fatigue Behavior of Titanium Alloys, ed. R. R. Boyer, D. Eylon and G. Lutjering, TMS, pp. 23-30