Engineers at the University of Maryland have found a way to make wood more than ten times stronger and tougher than before, creating a natural substance that is stronger than many titanium alloys.
The new wood is both strong and tough, “a combination not usually found in nature,” Teng Li, a professor of mechanical engineering at the University of Maryland, said in a statement.
“It is as strong as steel, but six times lighter. It takes 10 times more energy to fracture than natural wood. It can even be bent and moulded at the beginning of the process.”
The new wood is comparable to carbon fibre but just a fraction of the cost, added Liangbing Hu, the leader of the team that did the research. It is also five times thinner than its original size.
The team began by removing the wood’s lignin, the part of the wood that makes it both rigid and brown in colour, which they then compressed at around 65 degrees Celsius. This causes the cellulose fibres to become very tightly packed, crushing together any defects like holes or knots. The treatment process was then enhanced with a coat of paint.
The new type of wood opens the door to the design of lightweight, high-performance structural materials where high strength, large toughness and superior ballistic resistance are required. Possible applications include cars, aircraft or buildings. “Any application where steel is used,” said Hu.
Huajian Gao, a professor at Brown University, who was not involved in the study, called the method “particularly exciting” as it can be used for different species of wood and is also fairly easy to implement.