TY - JOUR
T1 - A new approach to compute T-stress in functionally graded materials by means of the interaction integral method
AU - Paulino, Glaucio H.
AU - Kim, Jeong Ho
N1 - Funding Information:
We gratefully acknowledge the support from NASA-Ames, Engineering for Complex Systems Program, and the NASA-Ames Chief Engineer (Dr. Tina Panontin) through grant NAG 2-1424. We also acknowledge additional support from the National Science Foundation (NSF) under grant CMS-0115954 (Mechanics & Materials Program). In addition, we would like to thank three anonymous reviewers for their valuable comments and suggestions. Any opinions expressed herein are those of the writers and do not necessarily reflect the views of the sponsors.
PY - 2004/9
Y1 - 2004/9
N2 - A "non-equilibrium" formulation is developed for evaluating T-stress in functionally graded materials with mixed-mode cracks. The T-stress is evaluated by means of the interaction integral (conservation integral) method in conjunction with the finite element method. The gradation of material properties is integrated into the element stiffness matrix using the so-called "generalized isoparametric formulation". The types of material gradation considered include exponential, linear, and radially graded exponential functions; however, the present formulation is not limited to specific functions and can be readily extended to micromechanics models. This paper investigates several fracture problems (including both homogeneous and functionally graded materials) to verify the proposed formulation, and also provides numerical solutions to various benchmark problems. The accuracy of numerical results is discussed by comparison with available analytical, semi-analytical, or numerical solutions. The revisited interaction integral method is shown to be an accurate and robust scheme for evaluating T-stress in functionally graded materials.
AB - A "non-equilibrium" formulation is developed for evaluating T-stress in functionally graded materials with mixed-mode cracks. The T-stress is evaluated by means of the interaction integral (conservation integral) method in conjunction with the finite element method. The gradation of material properties is integrated into the element stiffness matrix using the so-called "generalized isoparametric formulation". The types of material gradation considered include exponential, linear, and radially graded exponential functions; however, the present formulation is not limited to specific functions and can be readily extended to micromechanics models. This paper investigates several fracture problems (including both homogeneous and functionally graded materials) to verify the proposed formulation, and also provides numerical solutions to various benchmark problems. The accuracy of numerical results is discussed by comparison with available analytical, semi-analytical, or numerical solutions. The revisited interaction integral method is shown to be an accurate and robust scheme for evaluating T-stress in functionally graded materials.
KW - Conservation integral
KW - Finite element method (FEM)
KW - Functionally graded material (FGM)
KW - Generalized isoparametric formulation (GIF)
KW - Interaction integral
KW - Stress intensity factor (SIF)
KW - T-stress
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U2 - 10.1016/j.engfracmech.2003.11.005
DO - 10.1016/j.engfracmech.2003.11.005
M3 - Article
AN - SCOPUS:1842785547
SN - 0013-7944
VL - 71
SP - 1907
EP - 1950
JO - Engineering Fracture Mechanics
JF - Engineering Fracture Mechanics
IS - 13-14
ER -