Structural Engineering and Mechanics

  • 제16권1호
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  • Pages.47-62
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  • 2003
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  • 1225-4568(pISSN)
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  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

Optimal response of conical tool semi angle in ductile metal sheets indentation and its governing mechanics

  • Nazeer, Malik M. (Dr. A. Q. Khan Research Laboratories) ;
  • Khan, M. Afzal (Dr. A. Q. Khan Research Laboratories) ;
  • Haq, A-Ul (Dr. A. Q. Khan Research Laboratories)
  • 투고 : 2002.05.15
  • 심사 : 2003.03.27
  • 발행 : 2003.07.25
⟨ 이전 논문 다음 논문 ⟩

초록

The nonlinear dependence aspect of various conical tool indentation parameters leading to an optimum tool semi angle value for easiest perforation is plotted and discussed explicitly in this work with the conclusion that tool angle has an optimum response towards most of the indentation parameters. Around this optimum angle, the aluminium sheets showed minimum fracture toughness as well as minimum work input to overcome the offered resistance. At the end, the mechanism leading to this phenomenon is presented with the conclusion that plastic flow dominates as the dimple semi cone angle reaches 35 and both pre and post plastic flow perforations lead the tool semi cone angle value towards this dimple cone semi angle of plastic flow initiation for its optimum performance. It is also concluded that specimen material failure is solely under tensile hoop stress and hence results into radial cracks initiation and propagation.

키워드

참고문헌

  1. Atkins, A.G. and Mai, Y.W. (1988), Elastic and Plastic Fracture, John Wiley, Chechester, UK.
  2. Atkins, A.G., Khan, M.A. and Liu, J.M. (1998), "Necking and radial cracking around perforation in the sheet of normal incidence", Int. J. Impact Eng., 21(7), 521-539. https://doi.org/10.1016/S0734-743X(98)00010-4
  3. Giessen, E.V.D., Estevez, R., Pijnenburg, K.G.W. and Tijssens, M.G.A. (1999), "Computational modeling of failure process in polymers", Proc. of ECCM99 European Conf. Comput. Mech., Aug. Sept.
  4. Horne, M.R. (1979), Plastic Theory of Structures, Pergamon press.
  5. Johnson, W., Chatkara, N.R., Ibrahim, A.H. and Dasgupta, A.K. (1973), "Hole flanging and punching of circular plates with conically headed cylindrical punch", J. Strain Analysis, 8, 228-242. https://doi.org/10.1243/03093247V083228
  6. Johnson, W. and Mellor, P.B. (1983), Engineering Plasticity, edited by Atkins A.G., Ellis Harwood, Chechester, UK.
  7. Khan, M.A., Nazeer, M.M., Naeem, A., Haq, A-ul and Atkins, A.G. (1995), "Computer modeling of elastoplastic fracture mechanics of ball indentation in ductile aluminum sheet", Proceedings of '95 EUROMAT, European Conference on Advanced Materials and Processes, Symposium D, Padua/Venice Italy, September.
  8. Khan, M.A. (1996), "Indentation and perforation in ductile metal sheets", Ph. D. Thesis, Reading University, Reading, UK.
  9. Khan, M.A., Naeem, A., Nazeer, M.M., Haq, A-ul and Atkins, A.G. (1993), "Analysis of curvature generation and fracture toughness of indented aluminium sheet", Proc. ISAM 1993, 3rd Int. Symp. on Advanced Materials, Islamabad, Pakistan, September.
  10. Khan, M.A. and Atkins, A.G. (1998), "Cutting of ductile metal sheet by asymmetric pointed tools", Journal of Material Processing Technology, 82, 172-178. https://doi.org/10.1016/S0924-0136(98)00038-7
  11. Knauss, W.G. (1993), "Time dependent fracture and cohesive zones", J. Eng. Mat. Tech., 115, 262-267. https://doi.org/10.1115/1.2904216
  12. Liebowitz, H. (1973), Fracture an Advanced Treatise, Vol.1-12, Academic press N Y, San Francesco, London.
  13. Nazeer, M.M., Khan, M.A., Naeem, A., Haq, A-ul and Atkins, A.G. (1995), "Mathematical analysis of indented aluminium sheet curvature", Proc. ICPAM 95 Int. Conference on Pure and Applied Mathematics, Bahrain.
  14. Nazeer, M.M., Naeem, A., Khan, M.A., Haq, A-ul and Atkins, A.G. (1997), "Metal sheet behavior in conical tool indentation", Proceedings ISAM 1997, 5th Int. Symposium on Advanced Materials, Islamabad, Pakistan, September
  15. Nazeer, M.M., Khan, M.A., Naeem, A. and Haq, A-ul. (2000), "Mathematical analysis of ductile metal sheets indentation with conical tool", Int. J. Mechanical Science, 42(7), 1391-1403. https://doi.org/10.1016/S0020-7403(99)00065-X
  16. Nazeer*, M.M., Khan, M.A., Naeem, A. and Haq, A-ul. (2000), "Response of ductile metal sheet parameters to the cone angle of an indenting conical tool", Int. J. Material Engineering and Performance, 9(5), 478-489.
  17. Timoshenko, S. (1986), Strength of Materials, Part 2, Advanced Theory and Problems, 3rd edition, CBS Publishers & Distributors, Delhi, India.
  18. Timoshenko, S. and Goodier, J.N. (1951), Theory of Plasticity, McGraw-Hill, N. Y.
  19. Weirzbicki, T. and Jones, N. (1989), Structure Failure, edited by Atkins, A.G., John Wiley & Sons, Inc.