Determination of the phase transition in Pb0.88Ln0.08Ti0.98Mn0.02O3 (Ln=La, Sm, Eu) piezoceramics based on the Stefan–Boltzmann law

A method for determination of the phase transition in piezoelectric ceramic based on the relationship expressed by the Stefan–Boltzmann law is reported, i.e., by means of the radiation that the piezoelectric ceramic emits when it is subjected to different temperatures. The experiment is performed in piezoelectric ceramic based on PbTiO3 modified by the partial substitution of rare earths for Pb in the Pb0.88(Ln)0.08Ti0.98Mn0.02O3 system (Ln=La, Sm, Eu). From the measured emitted radiation, the value of the emissivity is calculated for each type of piezoelectric ceramic.