Properties of lead-halide glasses in the PbBr2-PbCl2-PbF2-PbO-P2O5 system

PI series of new glasses in the PbBr2-PbCl2-PbF2-PbO-P2O5 systems have been prepared and some properties studied. The composition dependence of densit y, glass transition temperature (T-g), thermal expansion coefficient, water durability and optical transmission is reported. A glass in the PbBr2-PbCl 2-P2O5 ternary system has glass transition temperature as low as 146 degree sC and density as high as 4.75 g/cm(3). When PbO and/or PbF2 are introduced into the PbBr2-PbCl2-P2O5 system? the glass transition temperature and den sity of glasses grow higher obviously. The glasses in the PbBr2-PbCl2-PbF2- PbO-P2O5 system have density up to 5.84 g/cm(3), Most of the glasses exhibi t good water resistance and good weathering durability. The dissolution rat e in deionized water at 25 degreesC is in the order of 10(-4)-10(-5) mm/day . The introduction of PbO and/or PbF2 into the glasses does not have much i nfluence on their water resistance and weathering durability. The glasses i n the PbBr2-PbCl2-P2O5 system have relatively high thermal expansion coeffi cient (25 x 10(-6)/degreesC). (C) 2001 Published by Elsevier Science B.V.