The effect of porosities which can be occurred within FGMs
during the process of sintering has been investigated recently [16, 17,
18, 19]. Due to FGM beams are often used in thermal environment,
investigation on the influence of temperature on free vibration of
FGM beams has been studied by several authors [20, 21]. To the
author’s best knowledge, to the date only Wang and Wu considered
forced vibration of FGM beam in thermal environment under moving
loads [22], in which dynamic response of FGM beam under a
harmonic moving load has been studied by Lagrange method. It
should be emphasized that in the authors [22] studied axially FGM
perfect beams (without porosities), and only the case of uniform
temperature is considered. Mathematically, the uniform temperature
distribution is a special case of nonlinear temperature field, and it is
relatively simple from computational point of view. Investigation on
vibration of FGM beams in thermal environment thus is important
from both the research and practical points of view.