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

The Korean Society of Mechanical Engineers (대한기계학회)
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Interfacial Crack-tip Constraints and J-integrals in Plastically Hardening Bimaterials under Full Yielding

완전소성하 변형경화 이종접합재의 계면균열선단 구속상태 및 J-적분

  • 이형일 (서강대학교 기계공학과) ;
  • 김용범 (서강대학교 대학원 기계공학과)
  • Published : 2003.07.01
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Abstract

This paper investigates the effects of T-stress and plastic hardening mismatch on the interfacial crack-tip stress field via finite element analyses. Plane strain elastic-plastic crack-tip fields are modeled with both MBL formulation and a full SEC specimen under pure bending. Modified Prandtl slip line fields illustrate the effects of T-stress on crack-tip constraint in homogeneous material. Compressive T-stress substantially reduces the interfacial crack-tip constraint, but increases the J-contribution by lower hardening material, J$\_$L/. For bimaterials with two elastic-plastic materials, increasing plastic hardening mismatch increases both crack-tip stress constraint in the lower hardening material and J$\_$L/. The fracture toughness for bimaterial joints would consequently be much lower than that of lower hardening homogeneous material. The implication of unbalanced J-integral in bimaterials is also discussed.

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References

  1. Larsson, S. G. and Carlsson, A. J., 1973, 'Influence of Non-singular Stress Terms and Specimen Geometry on Small-Scale Yielding at Crack-Tips in Elastic-Plastic Materials,' Journal of the Mechanics and Physics of Solids, Vol. 21, pp. 263-277 https://doi.org/10.1016/0022-5096(73)90024-0
  2. Williams, M. L., 1957, 'On the Stress Distribution at the Base of a Stationary Crack,' Journal oj Applied Mechanics, Vol. 24, pp. 111-114
  3. Rice, J. R., 1974, 'Limitations to the SmallScale Yielding Approximation for Crack-Tip Plasticity,' Journal of the Mechanics and Physics of Solids, Vol. 22, pp. 17-26 https://doi.org/10.1016/0022-5096(74)90010-6
  4. Betegon, C. and Hancock, J. W., 1991, 'Two-Parameter Characterization of Elastic-Plastic Crack-tip Fields,' Journal of Applied Mechanics, Vol. 58, pp. 104-110 https://doi.org/10.1115/1.2897135
  5. Wang, Y.-Y. and Parks, D. M., 1993, 'On the Two-Parameter Characterization of Elastic-plastic Crack-front Fields In Surface-cracked Plates,' In Constraint Effects in Fracture, ASTM STP 1171, pp. 120-138
  6. O'Dowd, N. P. and Shih, C. F., 1991, 'Family of Crack-tip Fields Characterized by a Triaxiality Parameter- I. Structure of Fields,' Journal of the Mechanics and Physics of Solids, Vol. 39, pp. 989-1015 https://doi.org/10.1016/0022-5096(91)90049-T
  7. O'Dowd, N. P. and Shih, C. F., 1991, 'Family of Crack-tip Fields Characterized by a Triaxiality Parameter- II. Fracture Application', Journal of the Mechanics and Physics of Solids, Vol. 40, pp. 939-963 https://doi.org/10.1016/0022-5096(92)90057-9
  8. McClintock, F. A., 1968, 'A Criterion for Ductile Fracture by Growth of Holes,' Journal of Applied Mechanics, Vol. 35, pp. 363-371 https://doi.org/10.1115/1.3601204
  9. Rice, J. R. and Tracey, D. M., 1969, 'On the Ductile Enlargement of Voids in Triaxial Stress Fields,' Journal of the Mechanics and Physics of Solids, Vol. 17, pp. 201-217 https://doi.org/10.1016/0022-5096(69)90033-7
  10. Dodds, R. H., Jr., Shih, C. F. and Anderson, T. L., 1992, 'Continuum and Micromechanics Treatment of Constraint in Fracture,' UILUENG-92-2014, University of Illinois at Urbana-Champaign, Department of Civil Engineering
  11. Lee, H. and Heon, S., 2000, 'The 3D Surface Crack-front Constraints in Welded Joints, Transactions of KSME (A), Vol. 24, pp. 144-155
  12. Lee, H., Ham, J. and Kim, Y.-J., 1999, 'MBL Based Investigations of Interfacial Crack- Tip Constraints and J-integrals in Plastically Hardening Birnaterials,' Transactions of KSME (A), Vol. 23, pp. 1525-1535
  13. Rice, J. R. and Rosengren, G. F., 1968, 'Plane Strain Deformation Near a Crack Tip in a Power Law Hardening Material,' Journal of the Mechanics and Physics of Solids, Vol. 16, pp. 1-12 https://doi.org/10.1016/0022-5096(68)90013-6
  14. Parks, D. M., 1992, 'Advanced in Characterization of Elastic-Plastic Crack- Tip Fields,' In Topics in Fracture and Fatigue, A. S. Argon (ed.), Springer-Verlag, pp. 59-98
  15. ABAQUS User's Manual, 1998, Version 5.8, Hibbitt, Karlsson and Sorensen, Inc., Pawtucket, RI
  16. Du, Z.-Z. and Hancock, J. W., 1991, 'The Effect of Non-Singular Stresses on Crack-tip Constraint,' Journal of the Mechanics and Physics of Solids, Vol. 37, pp. 555-567
  17. Wu, S.-X., Mai, Y.-W. and Cotterell, B., 1990, Plastic ${\eta}$-factor ${\eta}_D$ of Fracture Specimens with Deep and Shallow Cracks,' International Journal of Fracture, Vol. 45, pp. 1-18 https://doi.org/10.1007/BF00012606
  18. Leevers, P. S. and Radon, J. C., 1982, Inherent Stress Biaxiality in Various Fracture Specimen Geometries,' International Journal of Fracture, Vol. 18, pp. 311-325 https://doi.org/10.1007/BF00012486