When it comes to metal that's being used in the automotive or aerospace industries, the higher its strength-to-weight ratio, the better. With that in mind, researchers from North Carolina State University and Qatar University have developed a new alloy that reportedly has a low density similar to that of aluminum, but that's 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, those metals are 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 NCSU's 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."
He additionally informed us that while carbon fiber very likely has a higher strength-to-weight ratio than the alloy, it also wouldn't be as tough – in other words, the alloy would be more likely to bend under an amount of stress that would cause the carbon to fracture.
More work still has to be done in the testing of the alloy, along with establishing a practical production method. Koch and his colleagues are also looking into replacing or eliminating the scandium that makes up 20 percent of the material, as it's very expensive.
The research paper was published this week in the journal Materials Research Letters.