Researchers at the University of Maryland in the US have developed a new type of super-strong wood, which could replace the use of steel in manufacturing.
Transforming natural wood into “a high-performance structural material” opens up multiple possibilities for applications in areas such as buildings, cars and airplanes.
Liangbing Hu, left, and Teng Li, right, are engineers at the University of Maryland, College Park who have found a way to make wood more than 10 times stronger and tougher than before. Credit: University of Maryland
“This new way to treat wood makes it twelve times stronger than natural wood and ten times tougher,” said Liangbing Hu, head of the research team, in a press release.
“This could be a competitor to steel or even titanium alloys, it is so strong and durable. It’s also comparable to carbon fiber, but much less expensive.”
“It is both strong and tough, which is a combination not usually found in nature,” said Teng Li, the co-leader of the team and the Samuel P. Langley Professor of mechanical engineering at the University of Maryland. His team measured the dense wood’s mechanical properties.
“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 molded at the beginning of the process.”
In the experiment, researchers removed the wood’s lignin, the part of the wood that makes it both rigid and brown in color. Then it is compressed under mild heat, at about (65 degrees C (150 F). This causes the cellulose fibers to become very tightly packed. Any defects like holes or knots are crushed together. The treatment process was extended a little further with a coat of paint.
The team tested their new wood material and natural wood by shooting bullet-like projectiles at it. The projectile blew straight through the natural wood. The fully treated wood stopped the projectile partway through.
“Soft woods like pine or balsa, which grow fast and are more environmentally friendly, could replace slower-growing but denser woods like teak, in furniture or buildings,” Hu said.
According to Dr Hu “this new way to treat wood makes it twelve times stronger than natural wood and ten times tougher. This could be a competitor to steel or even titanium alloys, it is so strong and durable. It’s also comparable to carbon fibre, but much less expensive”.