Vermiculite and Mica in refractory industry

Due to vermiculite’s refractory properties, good thermal insulation and low density, it is used for hot topping molten steel to reduce heat loss from ingots and ladles and generally as a loose-fill insulator.

For this, Vermiculite is normally bonded with alumina cements, fire clays and silicates to produce a wide range of vermiculite products which, depending on type and application can withstand hot face temperatures of up to 1,100 ⁰C.

The types of refractory products made using vermiculite are:

                Pre-fired clay bonded insulation firebricks

                cast able high alumina concretes for back up insulation

                High alumina bonded bricks, slabs and special shapes

                Silicate bonded insulating shapes and molded products

Mica in casting industry

Induction furnaces provide an energy efficient solution to processing for the foundry and steel industry. The induction heating of metal involves applying heat to a coil of copper wire that surrounds a non-conductive crucible, containing the material to be melted down.

An alternating current runs through the copper wire coil, which creates a rapidly reversing magnetic field that can penetrate the metal. This penetration then induces circular electric currents inside the metal, eventually breaking down its resistance.

However, due to the intense heat involved, the crucible lining must be able to withstand high temperatures, to maintain consistency and productivity. This is where the slip plane characteristics of mica roll as a furnace lining are so critical to foundry processes.

What Does a Slip Plane Do?

Successful production in foundries requires the deformation in the makeup of the metals the foundry is processing. This deformation occurs when there is a dislocation motion, arising from the metal materials and the furnace lining gliding along each other during processing.

Different metals have different slip planes, and to create the right degree of dislocation to break them down means also having the right slip plane material lining the furnace.

A superior furnace lining material will also extend the lifespan of the furnace lining, helping to maintain an even surface and prevent the presence of defects in the coil wall. Mica has key advantages for the foundry and steel industry as a furnace lining material.

When manufactured in laminate form, and supplied in rolls, mica combines excellent slip plane characteristics with both durability and flexibility. It is a thin but extremely tough material, which allows the furnace lining to expand and contract while protecting it against any abrasive damage.