Silica Aerogel Is One Of The Most Remarkable Materials
Silica Aerogel in Insulation is one of the most remarkable materials in the world for its unique physical properties. It has much lower density, thermal conductivity, and refractive index than any solid material, but at the same time it is extremely rigid and strong. This makes it a potential candidate for a variety of applications in the aerospace industry.
Using a special manufacturing process, silica aerogel can be made into extremely thin and light materials with a high thermal conductivity. This makes it an ideal material for thermal insulation and heat protection in spacecraft, satellites, rockets, automobiles, and aircrafts. Silica aerogel can also be used for acoustic insulation and vibration dampening. In addition, silica aerogel is highly transparent in the visible spectrum and can be used as an optical waveguide for the generation of nonlinear waves.
The development of silica aerogels is closely related to the development of modern aerospace technology. In the past, a number of projects were launched by NASA to explore various functions of silica aerogels, including space shuttle thermal protection and acoustic insulator for outer space vehicles. However, these projects did not succeed in commercialization because they were overly expensive.
In order to solve this problem, researchers have been working hard to develop more efficient and cheaper silica aerogels. The most promising development is the ambient pressure drying method, which can produce low-density silica aerogel with a thermal conductivity of only 0.02 W/mK at room temperature.
Compared to the traditional methods of producing aerogels, this new method has a significantly lower production cost and is also environmentally friendly. Moreover, this method does not require any aqueous solvents and can be easily scaled up for industrial use.
Another advantage of the ambient pressure drying method is that it can be used to make highly transparent silica aerogels. This can be useful for acoustic applications, since it can reduce the speed of sound in an aerogel by up to 100 m/s. In addition, it can improve the acoustic performance of an aerogel by adding different additives.
Silica aerogel can be doped with hollow opacifiers to increase its extinction coefficient and thus enhance its transparency. This is a simple modification that can significantly improve the performance of silica aerogels in applications such as energy-efficient buildings, cold chain transportation, and aerospace engineering.
The atomic force microscopy (AFM) technique is being widely employed to study the mechanical properties of silica aerogels. This technique allows us to visualize the interparticle connections within the pearl-necklace-like fractal network of the silica gel and can help to understand its complex mechanical structure. In addition, this technique can provide valuable information about the morphology and molecular structures of the aerogels.
The first mission to utilize a silica aerogel for space exploration was the Stardust Mission, launched in 1999 and aimed at rendezvousing with the Comet 81P Wild 2 and collecting hypervelocity particles to bring them back to Earth for further analysis. The Stardust mission was the first to successfully return a sample of interstellar dust, making it a milestone in the history of the aerospace field.