DOI QR코드

DOI QR Code

구성방정식에 따른 고무 분기점 거동 비교 연구

Comparative Study of Bifurcation Behavior of Rubber in Accordance with the Constitutive Equations

  • 박문식 (한남대학교 기계공학과) ;
  • 송승 (한남대학교 기계공학과)
  • 투고 : 2010.01.04
  • 심사 : 2010.04.22
  • 발행 : 2010.06.01

초록

설계 또는 해석을 위해 고무를 모델링할 때, 쓸 수 있는 구성방정식이 너무 많음으로 말미암아 종종 당황하거나 수수께끼 같은 일을 경험할 때가 있다. 어떤 모델들은 몇 개의 재료상수만을 갖지만 또 다른 모델들은 많은 수의 재료상수를 갖는다. 연구자들은 광범위한 실험데이터를 준비하여 신중하게 피팅을 하여야 한다. 본 논문에서는 먼저 8배 정도까지 큰 신장 영역에 대해 대표적인 고무재료의 구성방정식들을 비교해 보았다. 대부분의 공학적 응용에서처럼 상대적으로 변형이 적은 경우에는 연속체기반모델 또는 체인분자모델이 유사하게 쓰일 수 있지만, 대부분 생체적 거동에서 볼 수 있는 큰 변형의 경우에는 체인분자모델들이 더 유용함을 알 수 있었다. 구성방정식에 따른 분기점의 존재 여부를 알아보기 위하여 트렐로어 패치와 원통형 막대풍선에 대한 분기점 해석을 이론적 및 수치적으로 수행하였다. 키슬리의 조건식으로부터 트렐로어 패치에서의 분기점은 연속체기반 모델에서는 존재하였으나 체인분자모델에서는 존재하지 않음을 보였다. 원통형 막대풍선은 축신장 허용의 경계조건에 대해서는 모든 모델들이 분기점 거동을 보여주었다. 따라서 고무의 분기점 거동을 구하고자 할 때는 분기점의 존재유무 자체가 재료모델의 선정에 의존적이라 할 수 있다.

Modeling of rubber for design or analysis often requires confusing or complex work because there are a large number of constitutive models to be considered. Some models have few material constants, while others have many. Researchers have to prepare and fit extensive experimental data with caution and discretion. In this paper, we first compared some typical rubber models in which deformation was carried out by stretching up to around eight times the original size. We conclude that continuum-based models and chain molecular models can be used in the study of the small deformation in most engineering applications, but chain molecular models are preferred in the study of the large deformations in most biomaterial applications. As discrimination problems, Treloar's patch and cylindrical balloon stick are tested theoretically and numerically for studying bifurcation. In the case of Treloar's patch, by using the Kearsley's equation, we show that bifurcation exists for continuum-based models but not for chain molecular models. Both models show bifurcation in the cylindrical balloon stick. Therefore, in the analysis of the bifurcation of rubber showed that its existence also depends on the constitutive model selected.

키워드

참고문헌

  1. Treloar, L. R. G., 1975, The Physics of Rubber Elasticity, Oxford University Press.
  2. Xu, H., Cheng, Z. -Y., Olsen, D., Mai, T., Zang, Q. M. and Kavarnos, G., 2001, “Ferroelectric and Electromechanical Properties of Poly (Vinylidene - Fluoride - Trifluoroethylene - Chlorotrifluoroethylene) Terpolymer,” Appl. Phys. Lett. 78, pp. 2360-2362. https://doi.org/10.1063/1.1358847
  3. Pelrine, R. E., Kornblush, R. D. and Joseph, J. P., 1998, “Electrostriction of Polymer Dielectrics with Compliant Electrodes as a Means of Actuation,” Sensors and Actuators, A64, pp. 77-85.
  4. Von Meyer, K. H., von Susich, G. and Valko, E., 1932, “Die Elastischen Eigenschaften der Organischen Hochpolymeren und Ihre Kinetische Deutung,” Kolloid Zeitschrift (Colloid & Polymer Science), 59, pp. 208-216.
  5. Boyce, M. C. and Arruda, E. M., 2000, “Constitutive Models of Rubber Elasticity: A Review,” Rubber Chemistry and Technology, 73, pp. 504-523. https://doi.org/10.5254/1.3547602
  6. Haughton, D. M., 1980, “Post-Bifurcation of Perfect and Imperfect Spherical Elastic Membranes,” International Journal of Solids and Structures, 16, pp. 1123-1133. https://doi.org/10.1016/0020-7683(80)90067-0
  7. Destrade, M., Annaidh, A. N. and Coman, C. D., 2009, “Bending Instabilities of Soft Biological Tissues,” International Journal of Solids and Structures, 46, pp. 4322-4330. https://doi.org/10.1016/j.ijsolstr.2009.08.017
  8. Gent, A. N., 2005, “Elastic Instabilities in Rubber,” International Journal of Non-Linear Mechanics, 40, pp. 156-175.
  9. Goriely, A., Destrade, M., Ben Amar, M. 2006, “Instabilities in Elastomers and in Soft Tissues,” The Quarterly Journal of Mechanics and Applied Mathematics, 59, pp. 615-630. https://doi.org/10.1093/qjmam/hbl017
  10. Ogden, R. W., 1972, “Large Deformation Isotropic Elasticity - on the Correlation of Theory and Experiment for Incompressible Rubberlike Solids,” Proceedings of Royal Society of London, A326, pp. 565-584.
  11. Arruda, E. M. and Boyce, M. C., 1993, “A Three-Dimensional Constitutive Model for the Large Stretch Behavior of Rubber Elastic Materials,” Journal of the Mechanics and Physics of Solids, 41, pp. 389-412. https://doi.org/10.1016/0022-5096(93)90013-6
  12. Gent, A. N., 1996, “A New Constitutive Relation for Rubber,” Rubber Chemistry Technology, 69, pp. 59-61. https://doi.org/10.5254/1.3538357
  13. Boyce, M. C., 1996, “Direct Comparison of the Gent and the Arrudaboyce Constitutive Models of Rubber Elasticity,” Rubber Chemistry and Technology, 69, pp. 781-785. https://doi.org/10.5254/1.3538401
  14. Horgan, C. O. and Giuseppe Saccomandi, 2002, “A Molecular-Statistical Basis for the Gent Constitutive Model of Rubber Elasticity,” Journal of Elasticity, 68, pp. 167-176. https://doi.org/10.1023/A:1026029111723
  15. Fung, Y.C., 1993, Biomechanics: Mechanical Properties of Living Tissue, 2nd edn, Springer-Verlag, New York.
  16. Ogden, R. W., 1984, Non-Linear Elastic Deformations, Ellis Horwood Ltd.
  17. Wan-doo Kim, Wan-soo Kim, Dong-jin Kim, Chang-soo Woo, Hak-joo Lee, 2004, “Mechanical Testing and Nonlinear Material Properties for Finite Element Analysis of Rubber Components,” Trans. of the KSME (B), 28, pp. 848-859. https://doi.org/10.3795/KSME-A.2004.28.6.848
  18. Abaqus, General purpose FEA package, Abaqus Inc.
  19. Muller, I. and Strehlow, P., 2004, Rubber and Rubber Balloons: Paradigms of Thermodynamics, Springer.
  20. Kearsley, E. A., 1985, “Asymmetric Stretching of a Symmetrically Loaded Elastic Sheet,” International Journal of Solids and Structures, 22, pp. 111-119. https://doi.org/10.1016/0020-7683(86)90001-6
  21. Batra, R. C., Muller, I. and Strehlow, P., 2005, “Treloar's Biaxial Tests and Kearsley'S Bifurcation in Rubber Sheets,” Mathematics and Mechanics of Solids, 10, pp. 705-713. https://doi.org/10.1177/1081286505043032
  22. Haughton D. M. and Ogden, R. W., 1979, “Bifurcation of Inflated Circular Cylinders of Elastic Material Under Axial Loading - I. Membrane Theory for Thin-Walled Tubes,” Journal of Mechanics Physics of Solids, 27, pp. 179-212. https://doi.org/10.1016/0022-5096(79)90001-2