303-Se

303-Se is a free-machining 18-8 chrome-nickel stainless steel with machinability similar to 303 but with improved formability. Selenium, added to an 18-8 stainless steel that is ordinarily tough and difficult to machine, makes it so freely machinable that it can readily be handled on automatic screw machines at about 75% of the speed of C1212. This steel has displayed nongalling properties that make disassembly of parts easy and help to avoid scratching or galling in moving parts. 303-Se stainless has somewhat better formability than 303 Project 70® and should be considered for applications which involve cold-forming operations.