Share this page by mail Why are biosoluble felts a safe alternative to asbestos and to refractory ceramic fibre?
Final Advanced Materials' biosoluble fibre felts are a safe alternative to replace asbestos-based insulation or other refractory fibres. These fibres have low biopersistence, meaning the body can eliminate any inhaled fibre rapidly and naturally. These felts have a low thermal conductivity and a temperature resistance of up to 1,400°C, and are used primarily as oven coatings, but also as a customisable local thermal insulation.
High-temperature felts are frequently used in industry for the insulation of ovens. These are lightweight materials which are simple to use, and which provide excellent thermal insulation. They are used in several sectors such as foundry, glass working and ceramics. The choice of felt depends on the oven’s temperature, the chemicals and the heating process. Final Advanced Materials offers felts with different compositions and temperature resistances, most with low biopersistence meaning they pose no danger for the operators.
Felts made from carbon/graphite fibre are excellent at withstanding high temperatures, and are used up to 3,000°C. These felts are stable up to 2,000°C, but only in an inert, oxygen-free environment. Otherwise, they oxidise above 300°C. Unlike carbon/graphite felts, zirconia felts are resistant to temperatures up to 2,000°C, even in the presence of oxygen in the environment.
The only felts capable of withstanding a continuous exposure to temperatures exceeding 1,500°C are ceramic (Al2O3), zirconia (ZrO2) or graphite fibre-based felts. Each felt has specific constraints: graphite felts can only be used in an inert atmosphere or in a vacuum, while zirconia felts have poor mechanical properties, and ceramic fibre felts can only resist temperatures up to 1,650°C.
The other felt families (glass, silica, biosoluble, RCF, basalt, etc.) cannot withstand a continuous exposure to more than 1,260°C.
The material has a thermal conductivity of 0.06 W/m·K at 200°C, and 0.30 W/m·K at 1,000°C. It is substantially lower than that of conventional refractory materials (often between 1 and 2 W/m·K at these temperatures). The felts offered by Final Advanced Materials are available in several densities, ranging from 64 to 160 kg/m3. The higher the density, the lower the conductivity which can go as low as 0.20 W/m·K at 1,000°C.