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7.2.1 Increase the hardness of the steel

One way of preventing blunting is to make the steel harder. Steel can be made harder by changing the alloying elements in the steel and then heat treating the material after the knife has been manufactured. The problem with this route is that the alloying elements which make the knife harder detract from the corrosion resistance of the knife. Therefore a balance must be found between simply making the knife harder and making it less corrosion-resistant. Generally, the hardness of a range of kitchen knives from cheap to expensive is controlled to be in the range of 500–600 HV. However this hardness is still insufficient to preventWearand the knife will eventually need resharpening.


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