Transactions of the Korean Society of Mechanical Engineers A (대한기계학회논문집A)

The Korean Society of Mechanical Engineers (대한기계학회)
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High-Strain Rate Tensile Behavior of Pure Aluminum Single and Multi-Crystalline Materials with a Tensile Split Hopkinson Bar

인장형 홉킨슨 바 장치를 이용한 알루미늄 단결정 및 멀티결정재의 동적 실험

  • Ha, Sangyul (Dept. Corporate R&D Institute, Samsung Electro-Mechanics) ;
  • Jang, Jin Hee (Dept. of Mechanical Engineering, Pohang University of Science and Technology) ;
  • Yoon, Hyo Jun (Dept. of Mechanical Engineering, Pohang University of Science and Technology) ;
  • Kim, KiTae (Dept. of Mechanical Engineering, Pohang University of Science and Technology)
  • Received : 2015.06.22
  • Accepted : 2015.11.06
  • Published : 2016.01.01
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Abstract

In this study, we modified the conventional tensile split Hopkinson bar(TSHB) apparatus typically used for the high strength steel to evaluate the tensile deformation behavior of soft metallic sheet materials under high strain rates. Stress-strain curves of high purity single and multi-crystalline materials were obtained using this experimental procedure. Grain morphology and initial crystallographic orientation were characterized by EBSD(Electron Backscattered Diffraction) method measured in a FE-SEM(Field emission-scanning electron microscopy). The fractured surfaces were observed by using optical microscopy. The relationship between plastic deformation of aluminum crystalline materials under high-strain rates and the initial microstructure and the crystallographic orientations has been addressed.

본 연구에서는 연성 금속재료의 판상형 인장 시편에 대한 동적 물성을 측정하기 위한 인장형 홉킨슨 바(TSHB, Tensile split Hopkinson bar)의 수정 방법에 대해 논의하고, 이를 이용하여 고순도 알루미늄 단결정 및 멀티결정재의 동적 물성을 측정하였다. 시편의 초기 미세조직 및 결정학적 방위는 전자후방 산란회절(EBSD, Electron backscattered diffraction) 분석을 통하여 측정하였으며, 동적 변형 후 파단 형상을 광학 현미경을 통하여 확인하였다. 고속인장 변형 중 시편 내부에 발생하는 변형 분포는 디지털 이미지 상관(DIC, Digital image correlation) 기법을 이용하여 측정하였다. 이를 통해 동적 변형 중 나타나는 알루미늄의 거시적인 소성 변형과 결정학적 방위 및 미세 조직과의 상관관계에 대해 논의하였다.

Keywords

References

  1. Kolsky, H., 1949, "An Investigation of the Mechanical Properties of Materials at very High Rates of Loading," Proc. Phys. Soc., B 62, 676 https://doi.org/10.1088/0370-1301/62/11/302
  2. Hopkinson, B., 1914, "A Method of Measuring the Pressure Produced in the Detonation of High Explosives or by the Impact of Bullets," Philos. Trans. R. Soc. Lond. Ser. A 213, 437-456. https://doi.org/10.1098/rsta.1914.0010
  3. Nicholas, T., 1981, "Tensile Testing of Materials at High Rates of Strain," Exp. Mech. pp. 177-185.
  4. Jung, D.-T., 1994, "Split Hopkinson Pressure Bar Technique for Stress-Strain Measurement," The Korean Society of Mechanical Engineers Annuals Spring & Fall Conferences, pp. 33-34.
  5. Kang, W.-J., Cho, S.-S., H, H., Jung, D.-T., 1997, "High Strain Rate Tensile Test of Sheet Metals with a New Tension Split Hopkinsn Bar," Trans. Korean Soc. Mech. Eng. A, Vol. 21, No. 12, pp. 2209-2219. https://doi.org/10.22634/KSME-A.1997.21.12.2209
  6. Pang, J.H.L, 2012. Lead Free Solder: Mechanics and Reliability, Springer.
  7. Nemat-Nasser, S., Isaacs, J.B., Starrett, J.E., 1991, "Hopkinson Techniques for Dynamic Recovery Experiments," Proc. R. Soc. Lond., Vol. 435, pp. 371-391. https://doi.org/10.1098/rspa.1991.0150
  8. Rittel, D., Lee, S., Ravichandran, G., 2002, "Large Strain Constitutive Behavior of OFHC Copper over a Wide Range of Strain-Rates Using the Shear Compression Specimen," Mechanics of Materials, Vol. 34, pp. 627-642. https://doi.org/10.1016/S0167-6636(02)00164-3
  9. Kim, Y., Shin, S.Y., Kim, Y.G., Kim, N.J., Lee, S., 2010, "Effects of Strain Rate and Test Temperature on Torsional Deformation Behavior of API X70 and X80 Linepipe Steels," Metall. Mater. Trans., Vol. 41A, pp. 1961-1972.
  10. Lindholm, U.S. and Yeakley, L.M., 1968, "High Strain-Rate Testing: Tension and Compression," Exp. Mech., Vol. 8, pp. 1-9. https://doi.org/10.1007/BF02326244
  11. Khan, A.S., Liu, J., Yoon, J.-W., Nambori, R., 2015, "Strain Rate Effect of High Purity Aluminum Single Crystals: Experiments and Simulations," International Journal of Plasticity, Vol. 67, pp. 39-52 https://doi.org/10.1016/j.ijplas.2014.10.002
  12. Badulescu. C., Grédiac. M., Haddadi. H., Mathias. J. -D., Balandraud. X., Tran. H. -S., 2011, "Applying the Grid Method and Infrared Thermography to Investigate Plastic Deformation in Aluminium Multicrystal," Mechanics of Materials, Vol.43, pp. 36-53 https://doi.org/10.1016/j.mechmat.2010.11.001
  13. Wang, Y. and Cuitino, A.M., 2002, "Full-Field Measurements of Heterogeneous Deformation Patterns on Polymeric Foams Using Digital Image Correlation," International Journal of Solids and Structures, 2002, Vol. 39, No. 13, pp. 3777-3796 https://doi.org/10.1016/S0020-7683(02)00176-2
  14. ARAMIS System. ARAMIS User Manual-Software. Braunschweig, Germany : GOM GmbH, 2013.
  15. Hosford, W. F. Jr., Fleischer, R. L., Backofen, W. A., 1960, "Tensile Deformation of Aluminum Single Crystal at Low Tempratures," Acta Metallurgica, Vol. 8, pp. 187-189. https://doi.org/10.1016/0001-6160(60)90127-9
  16. Kocks. U. F., Mecking. H., 2003, "Physics and Phenomenology of Strain Hardening : the FCC Case," Progress in Materials Science, Vol.48, pp. 171-273. https://doi.org/10.1016/S0079-6425(02)00003-8