Preparation of La- and Mg-Modified PbTiO₃ Ceramics and Their Pyroelectric Properties

Abstract

The results of this study are summarized as follows:(1) Lanthanum- and magnesium-modified PbTiO3 (PLMT) ceramics were obtained by normal sintering using pure PbTiO3 as a packing powder for the crucible.(2) The tetragonality c/a of PLMT ceramics was nearly a constant value of 1.033 in the range of y=0-0.020. This result indicates that the added Mg2+ ions (0.066nm) partially substitute Ti4+ ions (0.068nm) at the B-site in PbTiO3.(3) The Curie point shifted to the lower-temperature side with increasing amount of Mg2+ ion addition.(4) The PLMT ceramics of y=0.005 exhibited the largest pyroelectric coefficient of 1.8×10-8C/cm2⋅K, which was nearly equal to that of PbTiO3-system ceramics. The PLMT ceramics are suitable as the element material of point-type pyroelectric IR detectors.