Yuji KAWANAKA

Development of New Solder Glasses based on Bi2O3 without PbO

Kazumasa MATUSITA

Solder glasses have low melting temperature and are used to sealing and adhesion. Since the solder glasses contain a large amount of lead oxide, it is presently demanded to develop lead free solder glasses. These glasses have contained PbO. Now, new solder glasses without PbO are needed. One of the new solder glasses without hazardous PbO is based on Bi2O3. In this study, glasses based on Bi2O3 were prepared and various properties of glass were measured. As a result, glasses having Tg below 350oC can be obtained. It is found that the glass transition temperatures are significantly different with type of crucibles used for melting. It is also found that the obtained glasses had enough capability for solder glasses. On the other hand, this glass melt especially corroded alumina crucible, and a lot of Al2O3 are dissolved in the melt. So, dissolved of Al2O3 was quantitatively analyzed. It was concluded that the glasses based on Bi2O3 are hopeful candidate as new solder glasses without PbO.