The Effects Of Different Kinds Of Additives On Low-melting Sealing Galss's Properties

Sealing glass, a new kind of packaging material, is very widely used because of its good thermal stability, chemical stability and extremely high mechanical strength.Campared to the normal sealing glass,low melting glass has raletively low melting point, which improves sealing properties obviously by making liquid phase appears at a low temperature?Lead Boron glass is selected as the basic low melting glass system.At the same time, different addtives are employed to investigate the influence on the properties of glass. The thesis get a kind of sealing glass with low melting temperature and excellent comprehensive performance.For the basic PbO-B₂O₃ glass, when PbO's content is 77 wt.%,the initial melting temperature is 465?, and the coefficient of thermal expansion?CTE? is 11.4062×10-6K-1 with the weight loss 7.31% on corrosion resistance test. The experiment introduce Sn, Bi₂O₃, ZnO, MgO and CaF₂ additves and reported the influences on properties of each additive.The conclusion is that, the employment of Sn elementary substance and CaF₂ reduced the initial melting temperature to 425? and 410?,respectively. The effect on reducing initial melting temperature is remarkable, but the stability is poor, SnO₂ and CaF₂ are observed. Bi₂O₃ addtive works on initial melting temperature slightly, but improved the liquidity effectively with 107.9% as well as the corrosion resistance ratio of 0.92%. The co-addition with MgO and ZnO reduces the initial melting temperature to 400?, the button diameter increasing percentage is 80.77%, the weight loss is 2.4%. PbO-B₂O₃-ZnO-MgO-Ca F2 is explored to be the system with the minimum initial melting temperature at 395? with good comprehensive performance. The CTE is 11. 7558×10-6K-1, and the corrosion weight loss is 1.42%. An ideal low melting sealing glass is obtained.