Steak Knife Made From Hardened Wood Is Three Times Sharper Than Steel

Scientists have used a new form of hardened wood to create a steak knife that is nearly three times sharper than a stainless steel dinner table knife. It can even be washed in the dishwasher! New Atlas reports: This hardy new form of wood is the handiwork of scientists at the University of Maryland, who set out to supercharge the material's natural strength, which lies in the cellulose packed inside. Cellulose is the primary component of wood, accounting for 40 to 50 percent of the material, and itself has a higher strength-to-density ratio than many engineered materials, including ceramics, metals and polymers. But the remainder of wood, made up of the binding materials hemicellulose and lignin, dilutes its overall strength and limits its applications. The authors of the study set out remove these weaker parts of the wood while preserving the cellulose structures.

'It's a two-step process,' says senior author Teng Li. 'In the first step, we partially delignify wood. Typically, wood is very rigid, but after removal of the lignin, it becomes soft, flexible, and somewhat squishy. In the second step, we do a hot press by applying pressure and heat to the chemically processed wood to densify and remove the water.' The hardened wood was then carved into a knife and coated in mineral oil, which counters the natural tendency of cellulose to absorb water, extending the lifespan of the material, preserving the blade's sharpness and making it dishwasher safe. According to the team, the hard wood knife is almost three times sharper than a stainless steel dinner table knife and is 23 times times harder than natural wood. It was used to cut through a medium-well done steak with ease. The team was also able to produce nails using the new hard wood. Not only were they rust-resistant but they were just as sharp as regular steel nails.

The research was published in the journal Matter.

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