SU1058924A1 - Stone casting - Google Patents

Abstract

STONE CASTING, including SiO-i, A2gOZ FejO, FeO, MnO, CaO, characterized in that. that, in order to reduce viscosity, shorten the melting time and energy consumption for melt preparation, it additionally contains Tio, and MgFg in the following ratio, wt.%: 42.9-44.9 SiOt 4.0-5.8 0, 5-0.8 6.0-8.2 FeO 6.0-7.6 MnO 5.0-6.8 CaO 0.2-0.4 TiO / j 0.4-0.5 Nap 25-35 MgFj

Description

The invention relates to the field of stone industry and can be used in the synthesis of new types of stone casting, to find application in the construction, chemical, metallurgical and other sectors of the Industry.

) 1 Various types of stone casting are known, obtained from rock melts, slags, technical raw materials, industrial wastes.

Known stone casting containing SiOj, a-0, MgO, FeO, and oxides of rare earth metals, which has good fluidity, ensuring good filling of casting molds and precise dimensions of the resulting castings {Yj.

However, a melt of known casting is characterized by an increased (7-8 p) viscosity at 1450-1500 s, at which it is homogenized and clarified. This requires additional costs for melting, which affects the cost of the finished product. In addition, this casting can not be obtained by methods of electric arc melting, which excludes the possibility of producing castings in plants that do not have natural gas.

The closest in technical essence and the achieved result to the invention is a stone cast composition containing May.%: SiO 47.6-53.9; AJjOj 3.2-3.6, Fe-gC 0,, 0i FeO 8.5-9.5, MnO tL-8.4; CaO 7,6-, b, CaF 15-25 2.

The melts of this composition have increased fluidity and are capable of hardening the surface layer in the glassy state. This allows the use of products as decorative and artistic. But due to the presence of a glassy crust, such a casting cannot be used for technical purposes, as it has low strength and abrasion resistance. Because of the high viscosity.; The length of the bench when preparing a melt is long, which requires considerable energy and increases the cost of casting.

The purpose of the invention is to reduce viscosity, reduce melting time and energy consumption for cooking melted.

 This goal is achieved by the fact that stone casting, including SiOg, Fe2.0j, FeO, MnO, CaO, SUPPLEMENTS contains TiOj, and MgF in the following ratio of components, wt.%:

SiOj.42,9-44,9

, 0-5,8

0.5-0.8

Fer, 0 ,,

6.0-8.2

F.eO

MnO

6.0-7.6

5.0-6.8

Cao

TiO-j

0.2-0.4

0.4-0.5

25-35

Msf2

Table 1 shows the stone casting compositions.

Magnesium fluoride contributes to a significant reduction in melt viscosity and a decrease in the duration of melting. An increase in the content of MgF2 introduced above 35% leads to a significant foaming during the melting of the charge, which prolongs the melting process. A decrease in the MgF2 additive content below, 25% leads to an increase in viscosity and melting time, causing additional energy consumption for melt preparation. The content of the remaining components is affected. linear properties of melts and physico-mechanical characteristics of the resulting material. An increase in the amount of Ap205 and the above mentioned limit values contributes to the formation of an excess free glassy phase, reducing the abrasive resistance and strength of the material, while also increasing the viscosity of the melt. Reducing the silicon oxide content below 9% aluminum below 4% and sodium below 0.4 % worsens the crystallization properties of melts. The crystallization capacity decreases, the viscosity increases and in the case of a decrease in the content of iron, titanium, manganese and calcium oxides below the specified limits. The increase in the number of oxides of titanium, iron, manganese and. Calcium above the presented limits leads to the formation of so-called dry materials, characterized by low strength and heat resistance. Casting the optimum composition contains the specified components in Kpj H4ecTBax presented in. table 1 (, part 2).

Sedimentary rocks, slags, industrial raw materials, industrial waste and additives in the form of MgF2 are used to obtain this material. The mixture is melted in electric arc furnaces, castings are obtained by casting melt into molds. After solidification of the melt, the casting is subjected to heat treatment - crystallization and annealing. The stonestone forming material has a crystalline structure. The mineral phase is represented by pyroxan. The products are painted in light gray, g & amply and green.

Table 2 presents the characteristics of the melt and the properties of the obtained stone cast.

A noticeable decrease in viscosity is observed in the low temperature region, which makes it possible to lower the pouring temperature to 1050-1150 ° C. Reduced viscosity allows pouring melts into any closed molds, as well as into molds using melted patterns, and producing both small parts of complex configuration and large shaped castings. Such products have high surface finish and increased dimensional accuracy.

The advantage of these compositions in comparison with the prototype is the ability to form materials of various structures. Depending on the heat treatment mode, castings can be obtained, which can be used as decorative and artistic, as well as in technical purposes.

Upon receipt of products from the melt-prototype, a glassy crust forming on their surface would not be recrystallized and turned into a solid crystalline state. This is due to the nature of the melts containing CaFj released as droplets in a glassy mass. During heat treatment, the glassy phase turns into a sieve-like substance (in which the crystals are 0.5-1 µm in size, and the amount of free glass is 40-50%. Therefore, such castings cannot be used in conditions of abrasive wear and destructive loads.

The resulting stone; the composition is of such a composition that the melt can, under certain crystallization conditions, form a substance of full crystalline structure / with a crystal size of 20-50 microns and an amount of free glass of 10-20%.

. depending on the requirements, the mode of solidification and heat treatment of castings is selected. In the case of obtaining decorative artistic products, castings are removed from the form after they are solidified and placed in a heat-treatment furnace for heat treatment. In the manufacture of technical casting, the castings are placed in a thermal furnace for crystallization, without removing them from the molds. Depending on the purpose of the casting, the crystallization temperature varies between 750-95cft: The crystallization time is determined by the dimensions of the product. After crystallization, the technical casting is subjected to annealing. As a result, after heat treatment, it is known. In this mode, decorative art products have a thin glossy glassy crust on the surface, which improves the appearance of the product. The structure of the material in the cross section is crystalline with a crystal size of 20-30 μm, the amount of free vitrified phase is 20-15%. Such products can be operated.

0 as decorative and artistic, as it does not undergo loads and abrasion.

Technical casting is subjected to this mode of heat treatment / that does not

5 has on the surface of a glassy crust. The structure of the casting throughout the cross section is uniform crystalline. The crystal size is 40–50 µm, and the amount of free glassy phase does not exceed 15%. The material has the required strength properties of b-800-825 kg / cm Cystir 0/010, 03 g / cm / A 2.5-2.65 gsm / cm G Such castings can be applied at

5 operation under conditions of mechanical stress and abrasive wear.

Stone cast products can be used in construction as de-.

0 creative and artistic, as well as in the metallurgical, ore-dressing, chemical industries of the industry in the form of shaped parts of complex shape (magnetic separator and hydrocyclone assemblies / chemical pump parts, agitators, reactors / precise gauges and dies, textile machine thread guides, etc. .).

Table 1

.1Table 2

Claims (1)

<claim-text> <table border = "1"> <tbody> <tr> <td rowspan = "2"> Composition </ td> <td colspan = "3"> Viscosity, P </ td> <td colspan = "3"> at ° C </ td> <td rowspan = "2"> Duration melting 20 kg of charge <sub> &gt; </ sub> missions </ td> <td rowspan = "2"> Shock strength in kg · cm / ‘/ cm <sup> 1 </ sup> </ td> <td rowspan =" 2 "> Flexural Strength 2 kg / cm </ td> <td rowspan = "2"> Caffee · * · cient abrasion, g / cm <sup> 2 </ sup> </ td> </ tr> <tr> <td> 1500 </ td> <td> 1400. } </ td> <td> 1300 </ td> <td> 1200 -4 </ td> <td> 1150 </ td> <td> 1100 </ td> </ tr> <tr> <td> 1 </ td> <td> 5.1 </ td> <td> '8.0 </ td> <td> 16 </ td> <td> 25 </ td> <td> 46 </ td> <td> 72 </ td> <td> 50-60 </ td> <td> 2.50 </ td> <td> 800 </ td> <td> 0.02 </ td> </ tr> <tr> <td> 2 </ td> <td> 4.5 </ td> <td> 7.0 </ td> <td> 11 </ td> <td> 17 </ td> <td> 33 </ td> <td> 50 </ td> <td> 40-45 </ td> <td> 2.65 </ td> <td> 825 </ td> <td> 0.01 </ td> </ tr> <tr> <td> 3 </ td> <td> 4.0 </ td> <td> 6.1 </ td> <td> 10 </ td> <td> 19 </ td> <td> 29 </ td> <td> 41 </ td> <td> 35-40 </ td> <td> 2.60 </ td> <td> 815 </ td> <td> 0.03 </ td> </ tr> <tr> <td> 4 </ td> <td> 3.5 </ td> <td> 5.0 </ td> <td> 8.0 </ td> <td> 16 </ td> <td> 24 </ td> <td> 39 </ td> <td> 45-50 </ td> <td> 2.50 </ td> <td> 805 </ td> <td> 0.04 </ td> </ tr> <tr> <td> 5 </ td> <td> 6.0 </ td> <td> 10 </ td> <td> 19 </ td> <td> 36 </ td> <td> 60 </ td> <td> 110 </ td> <td> 65-75 </ td> <td> 2.40 </ td> <td> 780 </ td> <td> 0.06 </ td> </ tr> <tr> <td> Prototype </ td> <td> 5.5 </ td> <td> 8.5 </ td> <td> 17 </ td> <td> 30 </ td> <td> 50 </ td> <td> 80 </ td> <td> 65-75 </ td> <td> 2.30 </ td> <td> 700 </ td> <td> 0.10 </ td> </ tr> </ tbody> </ table>