This paper presents an explicit treatment of the generalized 2D thermopiezo
electric problem of an interfacial crack between two dissimilar thermopiezo
electric media by means of the extend Stroh formalism. In comparison with t
he other relevant studies, the present work has two features: one is that t
he crack is assumed to be a permeable slit across which the normal electric
displacement and the tangential electric field are continuous. The other i
s that the heat loading is applied at infinity, rather than on the crack fa
ces. As a result, the field intensity factors and the electric field inside
the crack are obtained in explicit closed-forms, respectively. As examples
, the solutions of several particular cases, including that of an impermeab
le crack and that of a homogeneous material with a crack are also presented
. It is shown that the electric field inside a crack may be singular and os
cillatory for the case of an interfacial crack, while for the case of a cra
ck in a homogeneous medium it is linearly variable. Moreover, it is also fo
und that for a homogeneous medium with a crack the stress intensity factors
based on the impermeable model and permeable model are same, but the inten
sity factor of the electric displacement is not.