Basalt fiber

Basalt fiber or fibre is a material made from extremely fine fibers of basalt, which is composed of the minerals plagioclase, pyroxene, and olivine. It is similar to carbon fibre and fiberglass, having better physicomechanical properties than fiberglass, but being significantly cheaper than carbon fibre. 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 tripods.

Manufacture

The manufacture of basalt fiber requires the melting of the quarried basalt rock to about 1,400°C (2,500°F). The molten rock is then extruded through small nozzles to produce continuous filaments of basalt fiber. There are three main manufacturing techniques, which are centrifugal-blowing, centrifugal-multiroll and die-blowing. The fibers typically have a filament diameter of between 9 and 13 µm which is far enough above the respiratory limit of 5 µm to make basalt fiber a suitable replacement for asbestos. They also have a high elastic modulus, resulting in excellent specific tenacity --three times that of steel.Verify source|date=March 2008

History

The first attempts to produce basalt fiber date to 1923 in the United States of America. These were further developed after World War II by researchers in the USA, Europe and the Soviet Union especially for military and aerospace applications. Since declassification in 1995 basalt fibers have been used in a wider range of civilian applications.

External links

* [http://www.sfsti.uzsci.net/basalt.htm The production of basalt fibers] Information from the Uzbekistan state scientific committee.
* [http://www.basaltex.com/ Information on the history and application of basalt fibers]
* [http://www.basaltfibre.com/eng/ Equipment and technologies for basalt fibers]
* [http://www.bpg.ge/ Range of basalt fiber products and applications]