1.1 This part of ISO 683 applies to the grades of wrought high-alloy materials listed in table 1. These valve materials are used for intake and exhaust valves in reciprocating internal combustion engines. It is applicable to bars, wire, wire rod and forgings and for the surface finishes listed in note 3 of 6.2. 1.2 This part of ISO 683 does not apply to alloys resistant to wear and corrosion which are used to protect valve seat surfaces. 1.3 In addition to this part of ISO 683, the general technical delivery requirements of ISO 404 are applicable.