440C Stainless Steel
Type 440C Stainless Steel provides the ability to achieve and maintain exceptional hardness and wear resistance as well as good strength and moderate resistance to corrosion. On the Rockwell C hardness scale, type 440C Stainless Steel measures between 58 and 65. Due to these advantages, alloy 440C is most often used in ball bearings and races, gauge blocks, molds and dies, valve components, knives, cutlery, and measuring instruments. It is recommended to machine type 440C Stainless Steel in its annealed condition with carbide or ceramic tools. It is not typically welded as it is prone to air hardening. If welding is necessary, the work piece must be preheated to 500° F. After welding, treat the metal for 6 hours at a temperature between 1350° F and 1400° F. Then, to avert cracking, the stainless steel must be furnace cooled slowly. Stainless steel alloy 440C Stainless Steel can only be marginally cold worked. When hot working, the metal must be kept at a temperature above 1700° F. Before beginning hot working, preheat the material to 1400° F and gradually increase to a temperature between 1900° F and 2200° F. After hot working, cool the work piece slowly until it reaches room temperature and then fully anneal it.