Crystallized structures of amorphous oxides

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Structure and crystallographic texture of Li2O-B203 crystallized under temperature gradients have been examined. 1) Specimens of 23-27mol%Li20 - 73-77Mol%B203 were heated in a Pt-10%Rh crucible for 1h at 873k and for 1h at 1273, and poured into a die with 15mm diameter and 3mm depth of cast iron and pressed with a plate of the same material. 2) The specimens were set on a stainless steel block heated at constant temperatures so that they might be crystallized under temperature gradients of about 5OK/mm. The temperatures of the block were controlled between 823K and 913K. 3) The crystallization begins on the surface in contact with the block. Spheroidal crystals with 0.1 - 5mm diameter grow into the matrix. They are composed of fibers. Four phases Li202B203, 2Li205B203, Li204B203-1, and Li204B203-I, are found in the layer near the surface, but only Li202B203 and Li204B203-I are present in the deeper layers. 4) Fiber-like crystallines of Li202B203 in the spheroidal crystals show preferred orientation. The indices are still not determined.