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Ceramic materials and products are materials which receive from substances similar to a powder in the various ways, they are exposed to obligatory thermal processing at heats for material hardening. Such treatment carries the name of burning. Among raw materials similar to a powder - clay which is applied often by manufacture of building ceramics.
On a structural sign all wares are divided into two groups: porous and dense. To porous those wares which show woter absorbtion over 5% on mass behave de bene esse: a brick is usual, tile, pipes of drainages. The dense are adopt wares with water absorbtion less 5% on mass, and they practically waterproof, for example tiles for a floor, sewage - pipes, acid - proof brick and tiles, travelling brick, sanitary porcelain. Absolutely dense ceramic wares not present, because evaporating water of shutting, entered in clay dough, always abandons a several mikro- and makrobrick. The distinctive feature of all ceramic wares and materials consists of their comparatively hardness durability, but small deformation. Аragility concerns negative properties of building ceramics more often. It possesses high chemical firmness and longevity, and the form and the sizes of products from ceramics correspond to the established standards or specifications.
Presently the supplies of natural raw material disappear gradually. Very much actual becomes question of the use of the second raw material, which appears as a result of activity of chemical, mining, coal industry, black and coloured metallurgy. These industries of industry along with the enormous issue of products are instrumental in the accumulation of plenty of wastes, which can contain valuable components for the production of different goods, including building materials.
The purpose of work and scientific by meaningfulness is research of properties of the second materials of raw materials and possibility of the use them for the production of building dense ceramics.
This work consists in the production of dense ceramic product from the stripping breeds of different clays with addition of plavney, and also selection of optimum compositions, modes and properties of wares.
The practical value of results of researches consists in the production of good product from stripping of clay breeds, which will answer the same technical requirements as well as products, made from raw material of first class, that will reduce in price the process of production of building dense materials considerably.
Analogues to the theme: "Dense ceramic materials with using secondary raw materials" of raw materials are not found. Mainly the students of previous years used description of the same technology of the plastic shaping of standards and the results of issledavaniy of similar materials of raw materials led.
Analogues it is not found a theme. Mainly there is advertising of ceramic and build materials, and similarly the articles on utilization of raw material and about ceramics.
Analogues it is not found a theme. Mainly there are the articles on description and utilization of the second raw material, and similarly about ceramic materials, raw material for the production of ceramics, ogneuporakh and advertising.
Dense ceramic wares are name such wares which differ a density, hardness and fine-grain. A crock in the wares of top grade has the white colouring, in the wares of lower sort – usually grey, yellow or brown.
Dense ceramic product
depending on their application it is possible to subdivide into a few :
1) build materials:
а) clinker brick;
б) tiles for a floor;
в) sewage-pipes;
2) apparatus and wares for productions, using chemical reagents:
а)brick and tile for liner of chemical apparatus, product for
agriculture;
б) chemical apparatus and its details;
3) economic - domestic wares:
а) tableware;
б) sanitary wares.
Picture 1 - Ceramic dense materials (Shots 6. Reiterations 5. A delay is 2 second. It is done in MP Gif Animator. Size 64,3 Kb).
Stone ceramic product have high mechanical hardness and acid - proofness. Therefore they are widely used in building, chemical industry, agriculture, to the sanitation and in home everyday life.
The indexes of technical properties of dense wares are resulted in a table 1.
Table 1: "Indexes of technical properties of dense wares"
| Indicator | Value |
| Tensile strength at a compression, кg/сm2 | 5800 - 8200 |
| Tensile strength at tension, кg/sm2 | 110 - 530 |
| Tensile strength at a fracture, кg/sm2 | 410 - 980 |
| Module of resiliency, кg/mm2 | 4200 - 5600 |
| Tensile strength at twisting, кg/sm2 | 210 - 320 |
| Tensile strength at a bend by a blow, кg sm/sm2 | 1,8 - 4,7 |
| Wear ot the action of sandy stream, sm3 | 2 - 5,0 |
| Coefficient of linear expansion 10-6 | 1 - 6,0 |
| Heat conductivity, ккаl/m*m2 hour grad | 2 - 4 |
A clinker brick is a brick, burnt to complete sintering of crock without an vitrification surface and signs of deformation.
Properties of clinker are characterized such indexes: tensile strength at a compression – ot 640 to 1400 кг/sм2, water adsorption – ot 0,9 to 5,5%, wear at strong motion on a road in the flow (10 – 12) of years; for a build clinker durability is at a compression – no less than 350 кг/sм2, for a hydrotechnical clinker water absorbtion – no more than 2,5%.Frost-resistance high – no less than 25 cycles of freezing at -15°C. By volume weight (1,85 – 1,95).
For making of clinker refractory clays are used mainly with the wide interval of sintering (190 – 200°С). At burning wares must sintering and not find out here the signs of deformation. The burnt product must possess high mechanical hardness.
By the basic constituents of clay raw material, influencing on the production of clinker brick are:
- Oxide of aluminium (17 - 25%). The oxide of aluminium is reduced by viscidity of alloy and allows to decrease deformation of brick in the process of burning.
- Oxide of iron (6 - 8%). Depending on the amount of iron in a clinker brick after burning good can be painted ot cherry - red to the darkly - violet color. However at overabundance of iron a continuous crust, impedimental the delete of carbon dioxide, appears on a clinker brick.
- Oxide of calcium (7 - 8%). Increase of maintenance of oxide of calcium in composition clay raw material obuslavlivaet increase of interval of sintering, that can multiply porosity of the prepared clinker brick. Thus there can be usadka and expansion and, as a result, deformation of brick in clay.
- Oxide of magnesium (3 - 4%). Substantial lack of clays of magnesias consists in tom, that they have large usadku relatively.
-Alkaline oxides (1,5 - 4,5%). The oxides of sodium and potassium are present in a two-bit in ceramic clay, and at insufficient spekanii or too high temperature of burning it is necessary to correct their composition by addition of plavney.
- Minerals of kaolinite group (20 - 30%). At the increase of maintenance of minerals of kaolinite group in composition clay the interval of sintering diminishes and rapid deformation of brick comes.
Other minerals in brick clays which are used for manufacture clinker a brick, are available in small amounts and do not influence formation process clinker.
A research object are stripping breeds of clays of deposit the "White beam" and rusinovskaya clay.
The presently obtained clay is exported abroad, and stripping breeds are lump in dumps and does not find application. Although at the analysis of chemical composition, it is possible to suppose about their possible the use for a production materials of silicates and product. For example, for the production of ceramic products – ceramic brick and tile, pipes, tile.
Therefore experimental part consists in research of properties of stripping of clay breeds and possibility of the use them for the production of building dense ceramics.
Approximate composition of the explored clays is resulted in a table 3
Table 3 "Approximate composition of the explored clays"
| Components | SiO2 | Al2O3 | Fe2O3 | MgO | CaO | K2O + Na2O | SO3 | losses at incineration |
| Content, % | 45 - 80 | 7 - 23 | 2 - 15 | 0,0 - 4 | 0,5 - 25 | 0,3 - 5 | 0 - 3 | 3 - 16 |
The first stage of experiment is research of information of stripping breeds on the row of properties. Shaping of standards takes place on plastic technology.
For making of standards on plastic technology clay was dried out at a temperature 100 - 110 °С, carefully ground down and sifted through a sieve 05. Weighed the hinge-plates of clay, mixed in a dry kind, shut water for the receipt of mass of normal working humidity, vacuumize. From the got mass shaped standards. After shaping standards dried out in natural terms and in a drying closet at a temperature 105 - 120 °С.
For determination of optimum interval of sintering of wares they were baked at temperatures 950, 1000, 1050 and 1100°С.
Main properties of ceramic wares it is been: water absorbtion, porosity, contraction, mechanical durability, closeness, frost-resistance, chemical firmness, decorative and other
Water absorbtion is name a relation, shown in the percents of mass of water, taken in a standard at a complete satiation to mass of dry standard.Water absorbtion settles accounts on a formula:
Where В – water absorbtion, %;
m - mass of dry standard, g;
m1 - mass of standard, saturated water, g.
Porosity of build materials is a degree of filling of volume of material by pores. On the size of pores materials subdivide on fine - pored and coarse - pored.
Air contraction is the substantial diminishing of volume of raw, what is going on at the delete of moisture as a result of drying.
Fire contraction is a change of sizes of good, what is going on at burning. Air and fire contraction on laboratory standards was determined by measuring of sizes of standards to drying, after drying and after burning.
A frost-resistance is ability of ceramic wares, saturated water, to maintain the frequent poperemennoe freezing in an air environment and thawing in water without the signs of destruction and without the considerable lowering of durability. An index of frost-resistance is an amount of teplosmen, which maintains a standard without the signs of destruction.
Mechanical hardness are characterized ability of material to resist all types of external influences with the appendix of force. On the aggregate of signs distinguish durability of material at a compression, bend, blow, twisting and other, hardness, plasticity, resiliency, wearing away.
Hardness is property of material to resist destruction under the action of tensions, arising up ot loading. Tensile strength at a bend settles accounts on a formula:
Where S – The settlement area of cross - section section of the sample, sm2 ;
Р - loading, кg;
Chemical firmness is ability of materials during great while to resist an action chemically of active reagents.
On the got standards air, fire and complete contraction, size of water adsorption and mechanical hardness was determined. These descriptions of standards are resulted in a table 4 (semisour kaolin, loams and ozheleznennyy kaolin from a deposit "White Beam" and clay of "Rusinovskogo" of deposit (R - 3)).
A table is 4 "Properties of raw material which is explored"
| Properties | Loam | Kaolin of ozheleznennyy | kaolin is semisour | Р - 3 |
| Absolute humidity, % | 26 | 17 | 12 | 20 |
| Number of plasticity | 26 | 29 | 18 | 30 |
| Shutting water, % | 34 | 35 | 29 | 32 |
| Complete water absorbtion, % | 25 | 26 | 22 | - |
| Air contraction, % | 11 | 14 | 7 | 7 |
| Fiery contraction, % | 4 | 0,3 | 1 | 3,9 |
| General contraction, % | 15 | 14,3 | 8 | 10,9 |
On the got results it is possible to do conclusion: this raw material can be used for the production of build ceramics, for example, of a build brick.
Thus information of stripping clay breeds can use in the production of build materials, that considerably will reduce in price the process of booty clay and process of production of build ceramics.
To make and explore on properties standards, sformovannye from clays of deposit "White Beam" and "Rusinovskogo of deposit" with addition of plavney: blast - furnace slag, nefelina, glass and perlita. Selection of optimum composition and interval of sintering. Shaping of standards will take place on technology of the moist pressing.