North Carolina State University scientists have developed a new approach for shielding military and space-based electronics from ionizing radiation.
The new technique relies on mixing oxidized metal powder – or rust – into a polymer, and then incorporating it into a common conformal coating on the relevant electronics.
“Our approach can be used to maintain the same level of radiation shielding and reduce the weight by 30% or more, or you could maintain the same weight and improve shielding by 30% or more – compared to the most widely used shielding techniques,” says associate professor Rob Hayes.
“Either way, our approach reduces the volume of space taken up by shielding.”
Ionizing radiation can cause significant problems for electronic devices, especially in space. Scientists have so far incorporated radiation shielding to protect them.
The shielding consists of an aluminum box that’s put around any sensitive technologies. This has been viewed as providing the best tradeoff between a shield’s weight and the protection it provides.
According to Hayes, NC State’s new rust-based technique offers to take the weight issue out of the equation.
“Metal oxide powder offers less shielding than metal powder would, but oxides are less toxic and don’t pose electromagnetic challenges that could interfere with a device’s operation,” says Hayes.
Supporting Hayes’ research is Mike DeVanzo, first author of the NC State study: “Radiation transport calculations show that inclusion of the metal oxide powder provides shielding comparable to a conventional shield.”
“At low energies, the metal oxide powder reduces both gamma radiation to the electronics by a factor of 300 and the neutron radiation damage by 225%.”
“At the same time, the coating is less bulky than a shielding box,” adds Hayes. “And in computational simulations, the worst performance of the oxide coating still absorbed 30% more radiation than a conventional shield of the same weight.”
According to Hayes, the oxide particulate is also much less expensive than the same amount of the pure metal.
Image and content: NC State