New alloy offers highest strength-to-weight ratio
Researchers from North Carolina State University and Qatar University have developed an alloy that has a low density similar to that of aluminum, but is stronger than titanium.
The material is a type of high-entropy alloy, meaning that it's made up of at least five metals in more or less equal amounts. In this case, it includes lithium, magnesium, titanium, aluminum and scandium.
"It has a combination of high strength and low density that is, as far as we can tell, unmatched by any other metallic material," said Dr Carl Koch, senior author of a paper on the research. "The strength-to-weight ratio is comparable to some ceramics, but we think it's tougher – less brittle – than ceramics."
The material is expected to find use in vehicles and prosthetic devices. The team is currently working to reduce or indeed eliminate the amount of scandium in it (currently 20%), as it's very expensive.
