Innovative Fibre Basalt

  • View
    643

  • Download
    9

Embed Size (px)

Text of Innovative Fibre Basalt

A Paper On

INNOVATIVE FIBRE ROCK FIBRE {BASALT}By Valia Sanket P. (sanketvalia@yahoo.com) Mob no: 9892916959 Gudhka Mihir P. (mhrgudka@gmail.com) Mob no: 9820333894

1

DKTE SOCIETYS TEXTILE & ENGINEERING INSTITUTE, ICHALKARANJI

INDEX

Serial no. 1 2 3 4 5 6 7 8 9

Content Abstract Introduction How Basalt is formed? Rock to Fibre! Properties of Basalt Fibre Scope of Basalt Fibre Field Applications Summary References

Page no. 3 4 5 6 9 10 11 12 13

2

1. Abstract Today significant and steady growth up to 10 % of manufacture of composite materials is observed in the world. One of the basic reinforcing elements of composite materials is fibers. Besides fibrous materials are widely applied in quality of thermal, sound-proof, and filtering materials. Therefore to present time it is executed a several works on development of modern "know-how" of continuous fibers from basalt stones, the producing of continuous basalt fibers and materials on their basis are started. Basalt is an environment friendly natural material. Basalt is the most common rock type in the earths crust. It is a hard, black volcanic rock with about 52% silica (SiO2) by weight. Basalt rock is a mixture of minerals that has a fine grain and slight differences in chemical composition. Common minerals in basalt include olivine, pyroxene, and plagioclase. It is similar to carbon fiber and fiberglass, having better physicomechanical properties than fiberglass, but being significantly cheaper than carbon fiber. It is used as a fireproof textile in the aerospace and automotive industries and can also be used as a composite to produce products such as camera tripods.

3

This paper will focus on the applications and the manufacturing techniques for a very common material, basalt rock, in a relatively new form, continuous filament basalt (CFB). During the past twenty years the technology was developed in the former Soviet Union to melt this once molten rock and form continuous fibers. The continuous strand of multiple filaments can then be twisted into a yarn, plied into a multi strand roving or cut into chopped fiber. The CFB can be converted into woven or nonwoven textiles or used to reinforce composite structures with techniques similar to those used with continuous filament fiberglass.

2. Introduction Basalt is a natural material found in volcanic rock. One third of the Earths crust consists of basalts and eruptive rocks, so it is easily available source. It is mainly used as crushed rock in construction, high way engineering and industrial purposes. Basalt also melts at around13001700C and can be spun into filament. The wide range of possible applications of basalt fibre results from its wide range of good properties. Basalt has good thermal, electrical and sound insulating properties. It can replace asbestos in almost all its possible applications (insulation) since the former has three times the latters heat insulating properties. When used as (continuous) fibres, basalt can reinforce a new range of (plastic and concrete matrix) composites. It can also be used in combination with other reinforcements (e.g. basalt/carbon). Some possible applications of basalt fibres and basalt-based composites are: thermal and sound insulation/protection (e.g. basalt wool, engine insulation), pipes, bars, fittings, fabrics, structural plastics, automotive parts, concrete reinforcement (constructions), insulating plastics and frictional materials. In this paper we will read about the basalt and its fibre in detail.

4

Chopped Basalt 1

3. How Basalt is formed? According to the US Geologic Survey, because of basalt's low silica content of about 52%, it has a low viscosity. Therefore, basaltic lava can flow quickly and easily move >20 km from a volcanic vent. The low viscosity typically allows gases to escape without generating enormous eruption columns. Basaltic lava fountains and fissure eruptions, however, still form explosive fountains hundreds of meters tall. Common minerals in basalt include olivine, pyroxene, and plagioclase. Basalt is erupted at temperatures between 1100 to 1250 C. Basaltic magma is commonly produced by direct melting of the Earth's mantle, the region of the Earth below the outer crust. On continents, the mantle begins at depths of 30 to 50 km. Shield volcanoes, such as those that make up the islands of Hawaii, are composed almost entirely of basalt. Huge outpourings of lava called "flood basalts" are found on many continents. The Columbia River basalts cover most of southeastern Washington and regions of adjacent Oregon and Idaho. In India Basalt rocks are found in Deccan Trap in Maharashtra in abundance. It is also found in Kutch, Saurashtra, Gujarat, Central India, Madhya Pradesh, Hyderabad region etc.

5

Basalt lava over Basalt Rock

4. Rock to Fibre! As we have seen earlier, Basalt rock is made from molten lava; i.e. it is made by melting of the earths crust. So Basalt rock is also malleable which helps in melting the rock and making a viscous solution which can be spun in fibre by melt spinning. Basalt doesnt degrade by melting as it has no toxic reactions with air, water, etc. and it is combustion & explosion proof. All these factors lead to easy spinning procedure. But Basalt needs high temperature range (about 1450C) to melt. Such temperatures cannot be achieved easily and needs proper attention of experts. Cost of extraction of basalt raw material is very low. The technology of production process is not hazardous for environment; It does not produce any emission or waste. Hence manufacturing cost is not vey high compared to other fibres. When in contact with other chemicals they produce no chemical reactions that may damage health or the environment. Basalt fiber is produced in a continuous process similar in many respects to that used to make glass fibers. Quarried basalt rock is first crushed, then washed and loaded into a bin attached to feeders that move the material into melting baths in gas-heated furnaces. Here, the process is6

actually simpler than glass fiber processing because the basalt fiber has a less complex composition. An overview of the basalt fiber manufacturing process is: A single-component basalt material is fed into a gas-fired furnace. The basalt is heated to about 1,450C (2,650 F) and melted. From the furnace, the molten material flows into a fore-hearth where the temperature of the molten material is more precisely controlled and distributed to each strand-making position. The molten material is gravity-fed from the fore-hearth at each forming position into a platinum alloy bushing. Electricity is passed through the bushing to provide a final stage of resistance heating and precise adjustment of the viscosity of the molten mixture. Each bushing has hundreds of micro-orifice each make a filament that is gathered into a single strand of continuous-filament basalt fiber. The no. of orifice (holes) and its diameter of the spinnerets are determined by the end use of the fibre. The combination of micro-hole size and viscosity of the melt determine the diameter of the resulting filaments (7-17). The basalt filaments are quenched with a water-based sizing to solidify the strands and deposit a small quantity of lubricant/bonding agent on the filaments. The strands are wound onto a bobbin called a forming package at high speed. The strands can then be sold as an untwisted roving, twisted/plied into a yarn for weaving, or chopped to a fixed length for production of a non-woven mat.

7

1. Batch silos: raw material supply, 2. Weighing, dosing and mixing, 3. Transport, 4. Batch charging, 5. Melting Furnace, 6. Fore-hearths (Spin pack), 7. Bushings, (continuous filament formation), 8. Sizing application, 9. Strand formation, 10. Traversing, 11. . Automated winder

"BFCMTD" (BASALT FIBER & COMPOSITE MATERIALS TECHNOLOGY DEVELOPMENT CO., LTD) and "BF&CM (BASALT FIBRE & COMPOSITE MATERIALS) Companies were developed and used a special technique to select the basaltic rocks, suitable for the production of continuous fibers. The companies have special knowledge and possess a big practical experience in selection of basalt breeds from which basalt fibers are made.8

Basalt fibre is produced mainly in contionous filament forms as it is easy to use the fibre as yarn with no. of filaments along its length and thus reducing the need of spinning. This fibre is also called as CBF (Continious Filament Basalt).

5. Properties of Basalt Fibres Safe and abundant, basalt rock has long been known for its thermal properties, strength & durability. This properties are passed onto the fibres also. It is well known that the properties of all mineral fibers depend on their chemical composition, thermal history, manufacturing conditions, filament diameter and composition of the chemical sizing applied. Glass fibers are made from a blend of raw materials whose recipe depends on the exact properties desired, i.e. E (electrical) grade, C (chemical resistant) grade, S (high strength) grade. Basalt fibers are made by melting a single material, basalt rock, with the properties determined by selection of the quarry from which the rock is obtained rather than a raw material recipe. Using a naturally occurring composition provides a high level of stability to basalt fiber.9

Some properties of Basalt Fibre: CFB meets the technical definition of a glass, however the presence of iron oxides gives basalt a golden brown color that doesnt have the translucence of fiberglass. Its operating temperature is as high as 820C (1500F). Density of CBF is 2.8gm/cc Elongation at break is 3.2% Tensile strength is 3450-4900 Mpa. Higher elastic modulus Better strength at elevated temperatures CBF is vibration resistant and will not powder like ceramic

View more >