Low Temperature Phase Transition Behavior of Ca-Doped Lanthanum Chromites

摘要

Phase transition of LaCrO_3 and doped-LaCrO_3 was studied by DSC, TG and XRD, and thermal expansion during the transition was analyzed. It is found that phase transition of LaCrO_3 begins at about 240 deg C and ends at about 265 deg C . Temperatures of phase transition rise obviously with increasing Ca~(2+) content. The transition of LaCrO_3 and Ca-doped LaCrO_3 from orthorhombic to rhombohedral is accompanied with endothermic reaction. No obvious change occurs in mass, but remarkable shrinkage occurs during phase transition.