| In recent years, PbO glass ceramics have been used widely in electron device field as sealing materials, whereas the injunction called "RoHS" has been put in practice from 1st July 2006, and Chinese government also has implemented an injunction, namely "Manage means control of pollution caused by products " from 1st March 2008, that banning PbO sealing glass ceramics in life electron equipment field, so that the lead-free sealing glass ceramics will play an important role in the future.Having sufficiently investigated the development and application demanding of the sealing glass and the glass-to-metal sealing, this investigation in the composition was improved. The glass power was prepared by high temperature melting. The transition temperature (Tg)and softening temperature (Tf)of the glass were tested, and the sealing glass ceramics were prepared by heat treatment.The effect of the balls, ball milling time and crucibles on the properties of the glass power was studied. The sealing glass ceramics rich in Bi2O3 was prepared by granulation, molding and heat treatment. The glass ceramics and glass power were charactered by DTA, XRD, dilatometry (DIL) and photo-microscope etc.In this investigation the volatilization of three kinds of binder were studied respectively. The methods of granulation and control of crystallization temperature were studied. The Tg, Tf and thermal expansion coefficient (a) of the two kinds of glass ceramics were also measured, the results indicate that the Tf of this system glass is low enough to seal the metal under low temperature, and the a matchs that of metal. It shows that the sealing glass ceramics rich in Bi2O3 meet the demand of environmental protection for lead-free, and it can replace of the traditional PbO system glass.The dielectric property, water durability and fluxion property of the two kinds of glass ceramics were tested, and the affecting factors were studied and the suggestion was also gived.
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