Fusible Glasses on the Basis of Boron-Phosphate Systems
Fusible, Environmentally Sound Glasses, Seal Glasses and Glass Frits on the Basis of Boron-Phosphate Systems
Tech Area / Field
- MAT-SYN/Materials Synthesis and Processing/Materials
3 Approved without Funding
Institute of Electronic Materials, Armenia, Yerevan
- Institute of Glass and Ceramics, Poland, Warsaw\nPennsylvania State University / Materials Research Institute, USA, PA, University Park\nAlfred University / School of Engineering, USA, NY, Alfred\nFriedrich-Schiller-Universität Jena / Otto-Schott-Institute für Glaschemie, Germany, Jena\nThe Natural History Museum, UK, London\nArgonne National Laboratory (ANL), USA, IL, Argonne\nUniversite de La Rochelle, France, La Rochelle
In the present Project development and research of environmentally sound, lead free, fusible glasses, seal glasses and glass frits with wide range of practical application and development of industrial engineering of their production in the indirect skull furnaces are expected.
Nowadays fusible glasses, seal glasses and glass frits are used widely in electronic technology, microelectronics and other fields of science and technology in various devices production. Glasses of PbO-B2O3-ZnO-SiO2 system are mainly the base of these materials. It is known a number of fusible glasses compositions used for obtaining of translucent dielectric coatings on different materials with (40-120)10-7 К-1 thermal coefficient of linear expansion (TCLE). The glass G-82-3 with ≈72 mass. % plumbous oxide contents is an illustration of translucent dielectric coating on different electronic circuits applied on window pane sheets.
The most common demesne of glass frits is color TV kinescopes production. In this field the glass frits with 440-470 єС flow temperature are worked out on the basis of these materials for vacuum-tight screen junction with funnel of color TV kinescope. PbO concentration in them ranges in 60-90 mass. %. The glass frits of analogous compositions are used also as protection coating on steel masking plates of color TV kinescopes.
Fusible glass frits and composite solder materials are used also for funnel splicing with screen of display tubes of different purposes, where leucosapphire, fiber-optics faceplates and others are used as screen material and different compositions оf electron-tube glasses, aluminum-oxide ceramics are used as funnel material.
Fusible glasses with high refraction index are used for glass microbeads making in polychromatic fluorescent coating materials production for traffic signalization and also as glazes and decorative coatings for porcelain, pottery, ceramics, glass and enamelware.
One of the topmost application fields of fusible multi-lead zincborosilicate glasses is the field of hybrid integration circuit (HIC) making, where these glasses are used in dielectric, resistive and conductive pastes preparation.
Thus, multi-lead fusible glasses wide applying stipulates their significance in action of different fields development of science and technology. However, analysis of these materials compositions shows that they developed mainly in very petty region of ZnO-PbO-B2O3-SiO2 glass forming system, and PbO toxical component contents ranges in 60-90 mas. %. PbO/B2O3 ratio in more compositions of seal glasses and glass frits is in the 2/1 range. At the PbO-B2O3 state diagram the 2PbOB2O3 compound corresponds to this ratio, fluxing at 768 єС.
Analyzing state-of-the-art of development, production and application of fusible glasses, seal glasses and glass frits it is apparently that environmental issues were not taken into account at pursuing an objectives in view before. Nevertheless these nowadays issues are of current concern and vital.
It is known also, that melts of multi-lead fusible glasses have considerable fluidity and high corrosivity to refractory. For example, at zincborosilicate seal glasses melt with PbO contents more than 50 mas. % in corundum or other multi-aluminous pots the Al2O3 transition in glass as a rule makes no less than 2 %, and pots are used no more than for 2 melts. At glass frit melt in bath batch furnace lined by corhart IAC-1711, furnace lifetime does not exceed 20 days, and considerable Al2O3 and ZrO2 transition in glass frit melt takes place. The platinum crucibles are most stable to fusible glasses and glass frits. However according to different literature data platinum transition in the melt in this case makes up 30-35 g. at 1 t. glass frit production with plumbous oxide contents something like 75 mass. %.
New lead free glass forming systems have been investigated by us for many years. The mechanisms of main physico-chemical properties change of synthesized glasses have been educed and practical compositions have been elaborated on their base. The trends of new lead free glass forming systems investigations and new compositions and technologies elaboration on their base have been worked.
Under the auspices of the Project it is expected development of lead free, environmentally sound glasses, seal glasses, glass frits, glass fluxes and other glass materials compositions and also problems solving of their production in furnaces of skull type without refractory with melt indirect heating.
The purpose of the Project is:
– determination of model compositions of glasses, seal glasses, glass frits and glass fluxes of ZnO-2PbOB2O3-SiO2 system;
– carrying out of scalenous research of RxOy-B2O3-P2O5 glass forming system (where RxOy – MgO, CaO, SrO, BaO, ZnO, Al2O3);
– working out of environmentally sound, lead free analogues of glasses, seal glasses, glass frits, glass fluxes on the basis of RxOy-B2O3-P2O5 system;
– determination of base compositions of glasses and glassy-crystalline materials of RxOy-B2O3-P2O5 system on the basis of model glasses and glassy-crystalline materials data of the ZnO-2PbOB2O3-SiO2 system.
– careful research of different environmentally sound modifying components influence on physico-chemical properties of base glasses and glassy-crystalline materials;
– research of developed glasses and glassy-crystalline materials melt process parameters in the indirect skull furnaces;
– investigation of more effective ways of skull furnace indirect heating for fusible glasses melt.
As a result of the Project the following problems will be solved:
– working out of fusible, uncrystallizable, toxic components free seal glass composition with (80-85)10-7 К-1 TCLE, analogue of G-82-3 glass;
– working out of lead free glass frit composition with 450-470 єС hermetic sealing and crystallization temperature and ≈(90-95)10-7 К-1 TCLE for screen junction with funnel of color TV kinescope;
– working out of lead free glass base for composite solder materials with (60-100)10-7 К-1 TCLE;
– working out of lead and other toxic components free glass composition with high refraction index for glass microbeads making for fluorescent coating of traffic signalization, advertising panels and exhibits;
– working out of environmentally sound, chemically stable to foodstuff glass fluxes for ceramic decorative paints production for glass, porcelain, pottery, ceramics, and enamelware;
– working out of optimal engineering parameters for the enumerated new glass materials production in elaborated construction of indirect skull furnace;
– reorientation of highly skilled scientists on the solving of peace problems;
– integration of scientists into the international community;
– facilitation to the Commonwealth of States in environmental problems solving.
The staff of scientists of Scientific Industrial Enterprise of Science of Materials long time has been engaging in development and manufacture of glasses, glass frits, glass fluxes for ceramic paints and various glass materials and has great experience in this field.
The authors of the Project invite scientists, research organizations, and also private experts from USA, the countries of European Community, Japan, Korea, and Norway to collaboration. We also offer to hold joint seminars and scientific research.
The International Science and Technology Center (ISTC) is an intergovernmental organization connecting scientists from Kazakhstan, Armenia, Tajikistan, Kyrgyzstan, and Georgia with their peers and research organizations in the EU, Japan, Republic of Korea, Norway and the United States.
ISTC facilitates international science projects and assists the global scientific and business community to source and engage with CIS and Georgian institutes that develop or possess an excellence of scientific know-how.