How Does Mica Sheets Manufacturing Work?

Posted by Axim Mica on April 29th, 2021

How Does Mica Sheets Manufacturing Work?

Mica’s myriad of amazing physical and chemical properties make it an ideal insulation material. But how are mica sheets manufactured?

Know the Process of Mica Sheet Manufacturing

Step 1:

The process of mica sheets starts with obtaining the raw mica. Mica occurs in nature in a crystalline form that is embedded in igneous rock. It is extracted either through deep shaft or open-pit surface mining; this process requires a high degree of precision and skilled labor as mica crystals can get damaged easily. After the careful extraction of the mica crystal, it is sorted carefully by hand, boxed, and sent off for processing. 

Mica occurs naturally in 37 types, but only two forms of mica, i.e., phlogopite mica and muscovite mica, are commonly used for industrial insulation applications. 

Step 2:

After reaching the processing facility, extracted mica goes through the process of assessing, grading, cutting, and splitting. The type and grade of the mica determine its use. Muscovite mica is stable up to 500 °C, whereas phlogopite mica remains stable at higher temperatures up to 900°C. After grading, mica is split into sheets. Mica naturally splits into the sheets due to its atomic structure, but these natural sheets are not ready for use and must go through the manufacturing process.

Step 3:

Natural mica sheets are grounded down into the divided particles using a hammer or other similar equipment. These grounded particles are then combined with water. A colloidal substance is added to the mixture, but its purpose is not to settle the mixture. It suspends the mica particles, which are applied to a mesh mold. The viscosity of the mica mixture allows it to form into even sheets.

Step 4:

The last step in manufacturing involves hard pressing of mica sheets with a resin to give them added strength. The process of adding resin includes soaking the sheets in the resin and drying it. Hydraulic presses are used to facilitate this process. Mica sheets are produced in two forms: rigid and flexible. The thickness of rigid mica sheets varies between 0.10mm and 50mm and flexible mica sheets between 0.10mm and 2mm.