Washington: To stand up to the heat and pressure of next-generation rocket engines, the composite fibres used to make them should be fuzzy, suggests a recent study.
The Rice University laboratory of materials scientist Pulickel Ajayan, in collaboration with NASA, has developed ‘fuzzy fibres’ of silicon carbide that act like Velcro and stand up to the punishment that materials experience in aerospace applications.
The fibres strengthen composites used in advanced rocket engines that have to withstand temperatures up to 1,600 degrees Celsius (2,912 degrees Fahrenheit). Ceramic composites in rockets now being developed use silicon carbide fibres to strengthen the material, but they can crack or become brittle when exposed to oxygen.
The Rice lab embedded silicon carbide nanotubes and nanowires into the surface of NASA’s fibres. The exposed parts of the fibres are curly and act like the hooks and loops that make Velcro so valuable – but on the nanoscale.
The result, according to lead researchers Amelia Hart, a Rice graduate student, and Chandra Sekhar Tiwary, a Rice postdoctoral associate, creates very strong interlocking connections where the fibres tangle; this not only makes the composite less prone to cracking but also seals it to prevent oxygen from changing the fiber’s chemical composition.
The work is detailed in the American Chemical Society journal Applied Materials and Interfaces. (ANI)