Effect of Temperature and Crack Tip Velocity on the Crack Growth in Functionally Graded Materials
The stress-fields near the crack tip for mixed-mode thermo-mechanical loading in functionally graded material (FGM) are developed using displacement potentials in conjugation with an asymptotic approach. The shear modulus, mass density and coefficient of thermal expansion of the FGM are assumed to vary exponentially along the gradation direction. Using insulated crack face boundary condition and steady state heat conduction assumption, the temperature field near to the crack tip is developed. By incorporating the developed temperature field equations with the displacement potentials, asymptotic thermo-mechanical stress field equations are derived. Finally, utilizing the minimum strain energy density criterion and the maximum circumferential stress criterion, the crack growth direction for various crack-tip speeds, non-homogeneity coefficients and temperature fields are determined.
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- 1.M. Niino, T. Hirai and R. Watanabe, The Functionally Gradient Materials, J. Jap. Soc. Comp. Mater., vol.13, no.1, pp. 257, 1987.Google Scholar
- 2.S. Suresh and A. Mortensen, Fundamentals of functionally graded materials, processing and thermomechanical behavior of graded metals and metal-ceramic composites. IOM Communications Ltd., London, 1998.Google Scholar
- 4.Erdogan and Wu, Crack problems in FGM layers under thermal stresses, J Therm Stress.1996; 19: 237-265.Google Scholar
- 6.Z.-H.Jin and G. H. Paulino, Transient thermal stress analysis of an edge crack in a functionally gradedGoogle Scholar
- 7.materials, Int. J. Fract., 2001; 107: 73-98.Google Scholar
- 8.Jain, A Shukla and R. Chona, Asymptotic stress fields for thermomechanically loaded cracks in FGMs, J ASTM Int., 2006; 3(7): 88-90.Google Scholar
- 9.Lee K.H, Chalivendra V.B, Shukla. A. Dynamic crack-tip stress and displacement fields under thermomechanical loading in functionally graded materials. J. Appl. Mech 2008; 75 (5): 1–7.Google Scholar
- 12.Erdogan F, Sih G. C. On the crack extension in plates under plane loading and transverse shear, J of Basic Eng, 1963; 85: 519-527.Google Scholar
- 14.Broek D. Elementary engineering fracture mechanics, Martinus Nishoff Publishers, 1978.Google Scholar