LaSr-manganate powders by crystallization of a borate glass

Abstract (LaSr)MnO 3 powders with perovskite structure were prepared in the basic system MnO 2 –SrO–La 2 O 3 –B 2 O 3 for the first time by a modified glass crystallization method. The annealing temperature was changed between 600 and 950°C. X-ray diffraction, magnetic measurements, ESMA and particle size investigations (specific surface) were carried out. The influence of the annealing conditions on the phase composition, the cation contents and the magnetic properties of the powders is discussed. Powder samples prepared under optimized conditions show values of specific saturation magnetization between 48 and 53 Am 2 /kg, a Curie temperature between 369 and 389 K and specific surfaces of about 10 m 2 /g corresponding to a mean particle size of 100 nm. The powders reveal the magneto-resistive effect.