• Гідрологія і Гідрометрія
• Господарське право
• Економіка будівництва
• Економіка природокористування
• Економічна теорія
• Земельне право
• Історія України
• Кримінально виконавче право
• Медична радіологія
• Методи аналізу
• Міжнародне приватне право
• Міжнародний маркетинг
• Основи екології
• Предмет Політологія
• Соціальне страхування
• Технічні засоби організації дорожнього руху
• Товарознавство продовольчих товарів

Viscosity silicate fusion.

Structure fusion silicate.

High temperature melting silicate (is usual from 500 0С up to 2000 0С) puts significant obstacles to research of their structure in molten a condition. To number of the most important properties silicate fusion, connected with their structure and investigated with sufficient completeness concern: viscosity, superficial tension and density.

Viscosity of substance in particular silicate fusion is understood as property of substance to render resistance mainly of one parts of a liquid concerning others. The existing methods of measurement of viscosity of glasses can be divided(shared) into 2 kinds:

1) Methods of definition of viscosity in rather low temperatures:

а) Method of a stretching of a string;

б) Method of a deflection of a string;

в) Method wrench of a core.

2) Method of definition of viscosity at high temperatures:

а) Method of a falling ball;

б) Method of rotating cylinders.

The role fusion by manufacture silicate of materials is rather various. Determining meaning(importance) have the properties silicate fusion for technology of a glass - product of cooling fusion without them crystallization. The vast role fusion and for technology of various materials received by them crystallization (fused refractory, cements, abrasive, monocrystals various thallic oxide, chalcogenides, halogenide and т is abundantly clear. д.). At the same time it is necessary to note and that large meaning(importance), which belongs fusion in technology of a number(line) of the basic multitonnage products silicate of technology, where they are that environment, in which there are many reactions of education of chemical connections determining at the end properties of ready products. The liquid phase in many respects defines(determines) also processes of sintering, т. е. Condensation of a material at burn many silicate of products.

It is possible to result many examples from various areas of technology silicate, which well illustrate a role fusion in technology silicates.

1. At baking portland cement clinker in rotating furnaces a liquid phase appearing in a zone of sintering, completely

Supervises process of formation main cement of a mineral - tricalium silicate с - alite ЗСаО · SiO₂.

2. By manufacture of one of most important fire-resistant

Materials - dinas the liquid phase also plays determining role. dinas - acid refractory, on structure approximately on 90 % (mass).

Consisting from SiO₂ and 10 % (mass). СаО. In the phase attitude(relation) is submitted basically tridymite.

3. By manufacture of porcelain the basic phase component of this material - mullite is formed by dissolution of quartz and products of decomposition kaolinite in feldspathic fusion.

Thus, nature and the properties fusion, raw materials, formed at high-temperature processing, by manufacture various silicate of materials, have huge practical meaning(importance), enabling a choice of optimum parameters of technological process and reception of materials with the beforehand given properties.

Questions:

What factors define(determine) absolute meaning(importance) of temperature melting of crystal substances?

Describe essence of existing modelling representations about a structure of liquids and, in particular, structure silicate fusion.

How influence temperature and structure silicate fusion their viscosity?

What defines(determines) size of a superficial tension and moistening ability fusion?

How it is possible to classify oxides on their influence on a superficial tension?

In what parameter and how it is possible to characterize moistening ability fusion?

Result examples of a role of a liquid phase by manufacture silicate of materials.

Читайте також:

1. Theme: Crystallization silicate fusion. Formation of the centres crystallization and growth of crystals.

Переглядів: 417