What is really sharp, durable and easy to use is the old kitchen knife that is quenched and forged and returned to the furnace, such as the national model cannonball steel hand kitchen knife. From ancient times to the present, all precious swords have been tempered. However, the modern machine technology is very fast, the labor cost is low, the traditional forging technology is less and less, and the chances of buying a good knife in the future are less and less.