Scientists make wooden knife that is sharper than steel
In the near future, the world's top chefs may be using knives made from wood. This may seem somewhat counter-intuitive, but materials scientists have created a wooden knife that is three times sharper than the stainless steel knives we use for dinner. The scientists are from the University of Maryland in the USA. Researcher Teng Li said wooden knives would complement the assortment of wooden utensils currently found in kitchens across the world. He said: "In our kitchen, we have many wooden things that we use for a very long time, like a cutting board, chopsticks, or a rolling pin. These new knives can also be used many times if you resurface them, sharpen them and perform the same regular upkeep."
Traditionally, knives have been made of steel or ceramics. The scientists improved the strength of the wood in their knives by enhancing the cellulose it contains. Cellulose is the main constituent of wood. It has a higher ratio of strength to density than most engineered materials, like steel and ceramics. Teng Li said the new cutting material is hardened to the extent that it can effortlessly slice through the toughest steak. There is an added advantage of wooden knives – they are environmentally friendly. They could end our dependence on plastic cutlery. The scientists have also developed wooden nails, which could be a boon to the building industry as they will not rust and weaken like conventional nails.
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