A Study on the Physical and Chemical Properties of Borosilicate Glasses

Abstract

For Borosilicate glasses B2O3 anormalies are often seen. The author made an experiment of transformation point, softeming point and chemical durability in the ternary system of Na2O-B2O3-SiO2 and expressed them in ternary diagrams.As the result, it was found that in the transformation points and chemical durabilities B2O3 anormaly appeared at the same position, but no anormaly was seen in softening points.Also he pointed out that in the composition of borosilicate glasses the way of utilization of anormaly differ from each other and hence the composition should be changed naturally in the case of aiming the sealing glasses such as electric bulb glasses or chemical resisting glasses.