A problem of thermoelectroelasticity for a piezoelectric material with a plane crack of arbitrary shape in a symmetric heat flow from the crack surfaces is solved. The crack is in a plane perpendicular to the polarization axis. We establish a correspondence between the stress intensity factor (SIF) and electric displacement intensity factor (EDIF) for a piezoelectric material with a plane crack and the SIF for a thermoelastic isotropic material with a crack of the same shape under the same thermal load. This correspondence allows finding the SIF and EDIF for an electroelastic material from the solution of the thermoelastic problem. The SIF and EDIF for a penny-shape crack (for different cases of thermal loading) and a half-plane crack are found as examples Keywords: thermoelectroelasticity, transversely isotropic material, plane crack of arbitrary shape, stress intensity factor, electrical displacement intensity factorIntroduction. In studying the distribution of mechanical and electric fields in piezoceramic bodies with cavities, inclusions, and cracks under mechanical, electric, and thermal loads [10,14,15,17,24], it is necessary to take into account the properties of new piezoelectric materials.General solutions of the system of coupled equations of electroelasticity in the three-dimensional case [9, 13, 23] were used in [10,14,[18][19][20][21][22] to solve some problems of electroelasticity for a piezoceramic body with cavities, inclusions, and cracks. The stress intensity factor (SIF) and electric displacement intensity factor (EDIF) for an electroelastic body with disk-shaped and elliptic cracks were studied in [1,10,[18][19][20][21][22]. The thermostressed state of elastic isotropic and transversely isotropic bodies with a disk-shaped or elliptic crack was analyzed in [6,7,11,16], and the thermoelectrostressed state of a piezoceramic body having an elliptic crack with homogeneous and linear temperature on its surface was studied in [20,22]. General patterns of variation in the SIF in a piezoceramic body having a plane crack of arbitrary shape with known temperature on its surfaces were established in [20]. Data on the SIFs for cracks in elastic bodies under mechanical and thermal loads can be found in the monographs [7,8,12,16].Numerous results for prestressed bodies with cracks are presented in [4]. Guz [2][3][4] was the first to use the correspondence between the solution for transversely isotropic prestressed bodies under mechanical loads and the solution for elastic isotropic bodies.We extend the approach of [2-4] to the case of coupled mechanical and electric fields in piezoceramic bodies with plane cracks under thermal loading. Note that the studies [18][19][20] are also based on the ideas of [2-4] but do not give any references to [2][3][4]. We will establish a correspondence between the SIF and EDIF for a piezoceramic body having a plane crack of arbitrary shape in the isotropy plane and subject to a symmetric heat flow from the crack surfaces and the SIF for a purely elastic isotropic body with a ...