Silica Aerogel - Aerospace Applications of Silica Aerogel

Silica Aerogel is an incredibly light and highly porous material. It is a very versatile material with many useful properties that can be exploited in numerous aerospace applications. One such application is thermal insulation. It can help reduce the amount of fuel needed for a vehicle to travel to its destination because it is very effective at keeping heat from escaping an area. Silica Aerogel in Insulation properties of silica aerogel also allow it to be used as a filler in composite materials. The insulating capabilities of silica aerogel can help keep an aircraft’s engines working efficiently while traveling at high altitudes.

Aerogel is an extremely porous material with a pore volume of 90% of the total volume. This is achieved by a special synthesis process that allows the gel to retain a large amount of water while maintaining its shape after all the water has evaporated. This process also allows the gel to maintain its structure even after being dried. The porosity of the material makes it very effective at insulating against thermal radiation. The thermal conductivity of silica aerogel is low enough to be incorporated into woven blankets that can be wrapped around the engines of a plane while it is flying at high altitudes.

The unique chemistry of silica aerogel is what sets it apart from other thermal materials. It is composed of a network of silica particles that are tortuously interlocked in a three-dimensional matrix. This network has many dead-ends that impede heat flow, making it an insulator with very low conductivity. Silica aerogel also has a high optical transmission rate and a low refractive index, which means that it transmits light very effectively. In addition, it can withstand high power inputs and does not show any boiling or melting phenomena.

Because of these impressive qualities, NASA began exploring the possibility of using silica aerogel as an insulator in space missions. In 1997, the Sojourner rover was sent into space with several thermally insulated boxes filled with silica aerogel to protect its battery pack and Alpha Particle X-Ray Spectrometer (APXS) from extreme temperatures.

NASA continued to test the performance of silica aerogel as an insulator for outer space missions. In 1992, five thermal insulated aerogel end covers were installed on the Shuttle Get Away Special (GAS) payload canisters to test its ability as a hypervelocity capture particle medium and endurance during launch and reentry. The aerogels survived launch and reentry without any visible damage.

To make the most of the potential of silica aerogel, a manufacturing process that produces high-quality blocks of the material has been developed. This manufacturing process uses a unique solvent, tetraethyl orthosilicate (TEOS) that is non-toxic. The resulting silica gel can be dried at ambient pressure and temperature. This method provides a more economical option than supercritical drying.

To increase the effectiveness of silica aerogel as an insulated material for aerospace applications, engineers have been experimenting with ways to combine it with other materials. They have found that silica aerogel granules can be embedded in transparent textile membranes to form a flexible, lightweight blanket that is both insulating and waterproof. However, the challenge is to combine the granules with these fabrics without creating any thermal bridges.