Magnesium has a number of potential advantages when it comes to engineering. It is considered the lightest of structural metals (those capable of bearing loads in buildings and cars) and it is the eighth most abundant element in the Earth's crust. On the flipside, however, it is not as strong and durable as some of its counterparts. Scientists are now reporting to have overcome its main limitations by infusing it with silicon carbide nanoparticles to form a new type of super-strong composite material, which they claim may lead to lighter and more efficient airplanes, spacecraft and cars.
"It's been proposed that nanoparticles could really enhance the strength of metals without damaging their plasticity, especially light metals like magnesium, but no groups have been able to disperse ceramic nanoparticles in molten metals until now," says Xiaochun Li, Professor of Mechanical and Aerospace Engineering at the University of California, Los Anglese (UCLA) and leader of the research team.
...At the heart of the UCLA team's breakthrough is a new manufacturing approach involving the use of silicon carbide, a super-hard ceramic...The resulting metal composite is made up of around 14 percent silicon carbide nanoparticles and 86 percent magnesium. In testing, the team found that it demonstrated record levels of both specific strength (how much weight a material can withstand before breaking) and stiffness-to-weight ratio. Furthermore, it also showed superior stability at high temperatures.