Lead-Free, Low-Melting SnO-MgO-P2O5 Glasses

• Main Authors: Chin-Hsien Yeh, 葉志賢
• Other Authors: Jiin-Jyh Shyu
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/31391186823193540548

碩士 === 大同大學 === 材料工程研究所 === 92 === The main objective of this thesis is to develop lead-free, low melting SnO-MgO-P2O5 glasses as an alternative to toxicity PbO-based soldering and sealing glass frits for low-temperature sealing applications. The glasses were melted in alumina crucibles for 10-30 min at 950-1200C. To maintain a reducing atmosphere during melting, addition of carbonaceous additive and N2 atmosphere is necessary. The melts were poured onto a Cu plate, and then annealed at 300C for 1-3 h. The glass formation region was examined in this study. The glasses are colorless. Glasses with a P2O5 content  35 mole% contained small bubbles. The increase in the MgO and P2O5 contents increased the melting temperature. The glasses have dilatomeric softening temperature (Tds) of 290-420C, glass transition temperature (Tg) of 270-400C, and thermal expansion coefficient (CTE) of 110-160 ×10-7 K-1. For the glasses with a constant P2O5 content, the decrease in the SnO/(SnO+MgO) ratio increased the glass melting temperature, Tg, and Tds, while decreases CTE. Moreover, in general, the chemical durability first increased then reduced. The dilatometric softening temperature and chemical durability of several glasses in the SnO-MgO-P2O5 system are better than the commercial PbO-ZnO-B2O3 frit.