It is particularly concerned with very low melting glasses with or without added ceramic fillers capable of hermetically sealing electronic ceramic parts such as alumina and beryllia in the 300 deg c range. This is even more important since platinum crucibles are often damaged during melting of phosphate glass batches, owing to severe corrosion of the platinum metal. The advantages of lead phosphate glass are noted to be low melting point. The phase composition and microstructure of the zr0.
The suitability and technical risk of three lowtemperature glass processing. Department of metallurgical and materials engineering what we need melting point, enthalpy and entropy of fusion of the constituents change of heat capacity cp cpl cps of the constituents if available excess gibbs energies of mixing of constituent binaries what we do generate a system of fusion equations for the constituents of the. Us6355586b1 us09494,434 us49443400a us6355586b1 us 6355586 b1 us6355586 b1 us 6355586b1 us 49443400 a us49443400 a us 49443400a us 6355586 b1 us6355586 b1 us 6355586b1 authority us united states prior art keywords wt glass powder ceramic composition melting point prior art date 19990225 legal status the legal status is an assumption and is not a legal conclusion. Critical melting points and reference data for vacuum heat treating vacuum furnace reference 1 ser i e s number. Us6355586b1 low melting point glass and glass ceramic. Material properties material properties for gases, fluids and solids densities, specific heats, viscosities and more. Towards rational design of lowtemperature cofired ceramic ltcc materials ji zhou. Candidate lowtemperature glass waste forms for technetium99. Most refractory materials consist of particles bonded together that have high melting temperatures.
Dielectric batio3 bbsz glass ceramic composition with ultralow sintering temperature. Defined as range because cooling rate will affect the temperature at which a melt becomes a glass and so cooling rate will affect macroscopic glass properties. Iso grade oils viscosities and densities viscosities and densities of iso and. This offers the materials engineer a wide choice of controlled fabric properties to satisfy design needs and objectives. Glass properties woven fiberglass fabrics offer the widest range and the best control over thickness, weight and strength of all forms of fiberglass textiles. At high temperatures, these particles melt and form slag. Us20060105898a1 low melting glass, sealing composition. At the melting point it is necessary that the thermometer bulb and the sample in the capillary tube be at thermal equilibrium. Disclosed is a leadfree, low melting point glass composition, which is characterized by being substantially free from a lead component and comprising 08 mass % of sio 2, 212 mass % of b 2 o 3, 27 mass % of zno, 0. The melting point of the refractory is the temperature at which a test pyramid cone fails to support its own weight. Fluid, stable glasses that are useful for low temperature sealing applications are made by adding jointly. Do not use hydrofluoric or hot phosphoric acid on glass. Glass properties on globalspec, glassonweb, matweb, glass global a general overview about glass art, history, science, literature, social studies, and technology is available at the corning museum of glass view as pdf, 1. In general, woven glass fabrics have the following properties.
Properties of pyrex, pyrexplus and low actinic pyrex. Fabrication and properties of novel lowmelting glasses in the. Glass network formers form the interconnected backbone glass network glass network modifiers present as ions to alter the glass network compensated by nonbridging oxygen nbo in oxide glasses usually reduce glass network connectivity intermediates can function as network formers or modifiers depending on glass composition. During the melting process, all of the energy added to a substance is consumed as. Further claimed are i a glass enamel composition comprising the above glass frit together with an oxide pigment component and an organic vehicle. The low melting glass of claim 1 wherein the composition includes at least one additive selected from the group consisting of. The composition of the low melting point glass powder is na2ocaosio2zno.
Also claimed is a glass frit produced from the above glass composition. A thin layer of glaze or sintered engobe improves decorative and functional properties of the final product. Not only sodalime glass, but also leadfree crystal, full lead crystal, opal and borosilicate glasses of differing compositions and water glass are. Polystyrene can be naturally transparent, but can be. Ddg, the leading glass products manufacturer and supplier in china, brings you low temperature melting point frit glass powder from its professional factory.
Glass is a noncrystalline, often transparent amorphous solid, that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Physical properties and chemical composition of code 7740 glass properties composition %approx. Ultralow sintering temperature glass ceramic compositions. Melting points freezing points documents giving melting or freezing point of elements and different kind of chemical species at varying conditions. Properties of glass materials 3 that occurs above the glasses melting point the liquidus line is known as stable immiscibility, whereas phase separation at temperatures below the liquidus is. Means for establishing the task to provide a conductive paste material which is characterized by containing a sio 2b 2 o 3 znoror 2 o type leadfree low melting point. Low melting point alloys lmpa or fusible alloys are normally classed as those alloys with melting points below 300 deg. Dielectric batio3bbsz glass ceramic composition with ultralow sintering temperature. Lowalumina glass development august 2002 prepared for the u. These three propertieslustre, transparency, and durabilitymake glass a favoured material for such household objects as windowpanes, bottles, and lightbulbs. Pure substances melt instantly at a specific temperature. Textiles e, r and d glass properties technical data sheet. A low melting glass, which contains substantially no lead and contains 7090% of bi 2 o 3, 120% of zno, 212% of b 2 o 3, 0.
This invention relates to novel low temperature sealing glasses. Melting and superheating of metals and alloys 291 table i. Our products made in china are low in price, high in quality and fine in workmanship. Though more difficult to make than traditional glass due to the high melting. Us20119326a1 lowmeltingpoint glass composition and. Pure crystalline substances have a clear, sharply defined melting point. Bhatnagar, in lightweight ballistic composites second edition, 2016. Composition development article pdf available in glass and ceramics 681112 march 2012 with 1,256 reads how we measure reads. Industrial glass, also called architectural glass, solid material that is normally lustrous and transparent in appearance and that shows great durability under exposure to the natural elements. Vapor pressure the vapor pressure of a substance liquid or solid is the equilibrium pressure of a vapor. Low melting glass composition vlsi packaging materials, inc. Low temperature glasses brookhaven national laboratory.
Lowmelting frits are most often applied in the form of coatings for ceramic building materials, i. Float glass furnaces with a melting capacity of 700 t24 h or more are an integral part of the programme, as is the smallest opal glass furnace for lighting ware, with a capacity of 1 t24 h. Disclaimer this report was prepared as an account of work sponsored by an agency of the united states government. Glass shatters when the stress is great enough, like when there is a large temperature difference in the glass. The complete spreading and softening temperature ranges are determined. It is a rather poor barrier to oxygen and water vapour and has a relatively low melting point. Critical melting points and reference data for vacuum heat. There are expected solutions which will allow obtaining a smooth layer of glaze. Is widely used in vacuum and microelectronics, laser and infrared technology, high energy physics, energy. The effect of the addition of bismuth iii oxide on the. Properties of pyrex, pyrexplus and low actinic pyrex code 7740 glasses. General purpose glass used in the container and plate glass industry. Typical properties of lowtemperature glass families. Glass is most often formed by rapid cooling of the molten form.
You could continue to heat what you have until it melts. Thermochemical optimization of float glass composition. Chemical glass cglass is highly resistant to attack by chemicals such as hydrofluoric acid, concentrated phosphoric acid when hot, and superheated water. A low melting glass composition comprising in weight percent calculated on an oxide. Schott research and development summarized their physical and technical glass properties 1. Low melting point glass powder low melting point glass powder is an advanced sealing material, the material has a lower melting temperature and sealing temperature, good heat resistance and chemical stability, high mechanical strength. Alternative glass compositions were proposed, based on reducing melt temperatures, improving durability, or providing compatibility with specific waste stream. Department of energy under contract deac0676rl01830. A disadvantage, from an environmental point of view, was the use of lead. Fabrication and properties of novel lowmelting glasses. Polystyrene is one of the most widely used plastics, the scale of its production being several million tonnes per year.
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