Titanium alloys are some of the strongest materials we can build with, but they can be expensive. Now, researchers at the University of Maryland (UMD) have come up with a way to make an alternative that literally grows on trees.
Using a new “densification” process, the team managed to make “super wood” that has the strength and toughness of steel.
Wood is already a pretty versatile material, but the leader of the UMD team, Liangbing Hu, has been working to give it an even longer list of uses. Over the last few years, Hu has developed transparent wood, burnt-wood water filters, and sodium-ion batteries based on wood and leaves.
The new “super wood” gets its super strength through a two-step process developed by Hu’s team. First, the researchers boil samples of wood in a watery mixture of sodium hydroxide and sodium sulfite, which works to partially remove lignin and hemicellulose from the material. Then, the treated wood is hot-pressed, which causes the cell walls to collapse and forms highly-aligned cellulose nanofibers. The end result is completely densified wood, which is much stronger than the natural stuff.