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Abstract
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In this paper, creep analysis of a thick-walled spherical pressure
vessel made of Functionally Graded Material (FGM) under thermomechanical loadings has been investigated based on Bailey-Norton
Law. Considering the nonlinearity of the creep behavior, there is no
analytical solution that can accurately determine the stresses of an
FGM as a function of time and thermal boundaries, thus in this paper,
a new method based on the Taylor Series expansion of the creep
strain rate is developed to solve the Beltrami-Michell equation by
employing an asymptotic method. The resulting quantities are
compared with the numerical ones and show good accuracy. The
impacts of FGM constants and wall-thickness, and series order on
the creep stress and strain distributions are evaluated. The results are
depicted graphically and reveal that even for vessels with high wall
thickness and FGM constants, the proposed method equipped with
high orders of the Taylor series produces accurate results. Also, due
to the agreement of both numerical and analytical methods, this
method can be generalized to study the creep of other symmetric
FGM structures.
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