Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
권호 표지
DOI QR코드

DOI QR Code

A Study on Plastic Deformation Characteristics and Formability for Pure Titanium Sheet

순 티타늄 판재의 변형 특성 및 성형성 평가

  • Received : 2018.04.20
  • Accepted : 2018.09.21
  • Published : 2018.10.01
Download PDF
⟨ Previous Next ⟩

Abstract

In this paper, tensile test was performed on pure titanium sheet (CP Ti sheet) with HCP structure in each direction to evaluate mechanical and surface properties and analyze microstructural changes during plastic deformation. We also evaluated forming limits of Ti direction in dome-type punch stretching test using a non-contact three-dimensional optical measurement system. As a result, it was revealed the pure titanium sheet has strong anisotropic property in yield stress, stress-strain curve and anisotropy coefficient according to direction. It was revealed that twinning occurred when the pure titanium sheet was plastic deformed, and tendency depends differently on direction and deformation mode. Moreover, this seems to affect the physical properties and deformation of the material. In addition, it was revealed the pure titanium sheet had different surface roughness changes in 0 degree direction and 90 degree direction due to large difference of anisotropy, and this affects the forming limit. It was revealed the forming limit of each direction obtained through the punch stretching test gave higher value in 90 degree direction compared with forming limit in 0 degree direction.

Keywords

References

  1. J.H. In, Y.S. Kim, 2017, Proc. 2017 Japan Spring Conf. Technol. Plast., J. Jpn. Soc. Technol. Plast., Japan, pp. 55-56.
  2. J.H. Park, 2009, Characteristics and applications of plate type heat exchanger, J. Korea Soc. Marine Eng., Vol. 33, No. 6, pp. 801-811. https://doi.org/10.5916/jkosme.2009.33.6.801
  3. Y.S. Kim, J.H. In, 2016, Evaluation of press formability of pure titanium sheet, J. Kor. Academia-Industrial Coop. Soc., Vol. 17, Issue 3, pp. 380-380. https://doi.org/10.5762/KAIS.2016.17.3.380
  4. Matsuo USUDA, 2002, Press formability of commercially pure titanium sheets, Nippon steel technical report, No. 85, pp. 24-30.
  5. Fuh-Kuo Chen, Kuan-Hua Chiu, 2005, Stamping formability of pure titanium sheets, J. Mater. Process. Technol., Vol. 170, pp. 181-186. https://doi.org/10.1016/j.jmatprotec.2005.05.004
  6. G.I. Taylor, 1938, Plastic strain in metals, J. Inst. Met., Vol. 62, pp.307-324.
  7. K.H. Ahn, H. Huh, J.H. Yoon, 2012, Effect of deformation twinning on strain hardening in Titanium, Proc. KSAE Spring Conf., Trans. Kor. Soc. Auto. Eng., pp. 1300-1309.
  8. S. Ishiyama, S. Hanada, O. Izumi, 1990, Orientation dependence of twinning in commercially pure titanium, J. Jpn. Inst. Metals., Vol. 54, No. 9, pp. 976-984. https://doi.org/10.2320/jinstmet1952.54.9_976
  9. S. Wronski, 2016, Microstructure evolution of titanium after tensile test, Mat. Sci. Eng. A, 656, pp. 1-11. https://doi.org/10.1016/j.msea.2015.12.041
  10. Y.S. Kim, 2017, Engineering plasticity and its application, Sigma Press, Korea.
  11. M. Ishiki, T. Kuwabara, Y. Hayashida, 2011, Measurement and analysis of differential work hardening behavior of pure titanium sheet using spline function, Int. J. Mater. Form., No. 4, pp. 193-204. https://doi.org/10.1007/s12289-010-1024-5
  12. J.W. Won, K.T. Park, S.G. Hong, C.S. Lee, 2015, Anisotropic yielding behavior of rolling textured high purity titanium, Mat. Sci. Eng. A, Vol. 637, pp. 215-221. https://doi.org/10.1016/j.msea.2015.03.096
  13. J.W. Feng, L.H. Zhan, Y.G. Yang, 2016, The establishment of surface roughness as failure criterion of Al-Li Alloy stretch-forming process, Metals, Vol. 6, Issue 1, pp. 1-10. https://doi.org/10.3390/met6010001
  14. G. Udupa, 2000, Characterization of surface topography by confocal microscopy: I. Principles and the measurement system, Meas. Sci.Technol., Vol. 11, No. 2000, pp. 305-314. https://doi.org/10.1088/0957-0233/11/3/320
  15. J.H. In, Y.S. Kim, 2016, A study on the surface characteristics by tensile deformation in pure titanium sheet, Proc. Kor. Soc. Tech. Plast. Conf., Korea, pp. 98-99.
  16. ZEISS, 2009, LSM 710 and Confocor 3 - Operating Manual, Germany.
  17. Hecker, 1972, A simple forming limit curve technique and results on aluminium alloys, sheet metal forming and formability, in 7th Biennal Conf. IDDRG, Amsterdam, pp. 5.1-5.8.
  18. ASTM E2218-02, 2008, Standard test method for determining forming limit curves, Annual Book of ASTM Standards, Vol.03.01, ASTM International, West Conshohocken, Pa.