Polishing rate of BaO-B₂O₃-SiO₂, PbO-SiO₂ and PbO-B₂O₃ glasses

BaO-B₂O₃-SiO₂, PbO-SiO₂ and PbO-BzO₃ glasses were polished using a pitch polisher and cerium oxide dispersed in distilled water. The factors affecting the polishing rate at initial stage were discussed in terms of glass properties: Vickers microhardnees, chemical water durability and bulk modulus. The polishing rate of BaO-B₂O₃-SiO₂ glasses depends mainly on the hardness of the hydrated layer formed; this factor is consistent with Izumitani proposal. The polishing rates of PbO-SiO₂ and PbO-B₂O₃ glasses increase with increasing PbO content up to 50 mol % PbO and then decrease remarkably. The polishing rates of PbO-SiO₂ and PbO-B₂O₃ glasses are apparently affected by the bulk modulus which is related to the product of the ratio of plastic strain to elastic strain (c/a) and the indentation hardness H using Hill's theory on plastic-elastic materials.