Borosilicate glass: characteristics, production and application
Providing traditional materials with specialcharacteristics has long been a common practice. Products with improved properties of chemical protection, increased heat resistance and hardness are used in power engineering, machine building, production of building materials and in other areas. At the same time, the narrow areas of application of the same fire-resistant products do not remain without attention. So, in medicine, borosilicate glass is widely used, the utensils of which are easy to use and have a wide range of protective properties.
Composition of glass
Technical and physical qualities of materialsare determined by two factors - the processing technique in the production process and the components of the primary element base. By and large this glass is a representative of a group of conventional silicate materials, which are based on oxides. This is a basic list of components, including carbon sodium, quartz sand and calcium oxide, that is limestone. In this case, borosilicate glass is distinguished by the presence in the composition and one more element, which in many ways determined the non-standard quality of the structure. In the total silicate composition, boron oxide is added, which ensures the stability of the glass to temperature differences. Of course, the composition of modern glass is not limited to this, as technologists modify the sets of elements, focusing on specific requirements for final products.
Glass manufacturing technology
In general, the method of manufacturing borosilicateThe material is similar to that of conventional glasses. In the process of cooking the main melt, furnace units with a temperature of more than 1300ºC are used. The liquid mass is molded on special metal panels. In the technique of the float process, a sheet borosilicate glass is produced with the specified dimensions. The peculiarity of this method is that the received sheets are not cut and are not corrected at all, but in the finished form they are used by the end user.
Of these glasses in the future are assembleddouble-glazed windows, doors, and in some cases also fireproof partitions. A lot of production involved in the production of such glasses, is focused on the manufacture of ready-made dishes. These can be test tubes, vessels, bowls and other items used in medicine and technical support of research centers. On special equipment, mechanical cutting and polishing of ingots is performed, from which further laboratory glassware is produced in various forms. Actually, the main difference in the manufacture of this material from conventional silicate analogues is the organization of the working process in conditions of a higher temperature.
Main characteristics of glass
Glass of this type is advantageous in many properties andperformance characteristics. First of all, this is a wide temperature range of the environment in which glass can be used. In the standard version, the material withstands frost to -80ºC and the heat at 525ºC. From the point of view of operation in laboratory conditions, resistance to chemical influences comes first. It is these qualities vested in a medical test tube. Borosilicate glass with its inertness is sufficient to ensure that the user can safely protect the contents from acids, salts, alkalis and organic compounds. The mechanical stability of this material is also noted. Since the density coefficient of the borosilicate base is higher than that of silicate glasses, it is better protected from the risk of physical damage. In addition, strong thermal effects do not destroy the surface of the glass into small fragments, and the panels burst, which form blunt and safe edges.
Sizes and format of issue
Specialized dishes are usually produced underOrder of laboratories and medical enterprises. However, the production of sheet materials provides for some production standards. In particular, the thickness of the glass panel can be 6-12 mm. In this case, the error usually does not exceed 0.3 mm. The maximum format in which sheet heat-resistant glass is produced is represented by a size of 150x300 cm. But, again, according to a special order, many enterprises expand these manufacturing parameters with the technological capability. As for the minimum values, it is customary to consider the 10x10 cm format as the smallest unit of production of such glass.
Applications
As already noted, the material characteristicsare best suited for use in laboratories, in equipping medical offices, etc. For such purposes, manufacturers produce bulbs, vessels, test tubes and other products. The vacuum tube of borosilicate glass, apart from its special physical characteristics, also has a structural feature. Although outwardly it may seem that this is one tube, in fact there are two of them and they form a vacuum. A sheet glass of this type also finds its application. It is usually used as partitions, in optical technology and when equipping premises with protective barriers.
Fireproof borosilicate glass
The quality of fire resistance is particularly appreciated- one of the key characteristics of borosilicate material. Manufacturers produce special panels for glazing and the device of door and window linens with increased protective qualities. In this case, for example, spider glazing differs not only in refractory properties, but also in mechanical resistance. A complete set of standard plastic window systems also uses heat-resistant glass, providing thermal protection. Fireproof materials for decoration of ceiling and floor surfaces are also distributed.
Limitations on the use of glass
Despite a wide range of profitabletechnical and operational properties, borosilicate products have some limitations on their use. As for interaction with an open flame, the material is capable of holding the fire for not more than an hour. This nuance does not allow the use of such glass in rooms with increased requirements for fire safety. There are also limitations for other applications. In particular, laboratory glassware does not withstand contact with hydrofluoric and hydrofluoric acids. Negatively affects the test tubes with flasks and caustic alkali, the effect of which is reinforced by high temperature. In itself, the extreme temperature regime does not destroy the glass, but sharp differences prevent the material from adapting the structure in time.
Conclusion
Borosilicate glass products are not worth itConsider as a special material for purposeful protection against chemical influences and fire. It can be said that these are secondary and even auxiliary characteristics, which are used to enhance the practicality of traditional products. Nevertheless, borosilicate glass, in addition to protective properties, retains properties such as transparency and light transmission capacity. Therefore, the combination of mechanical resistance, refractoriness and translucency allows us to consider the material as unique. At least, this is laboratory glassware, which, in addition to these characteristics, also has an optimal inertia.