Grade 430 is a ferritic, straight chromium, non-hardenable grade, combining good corrosion resistance and formability characteristics with useful mechanical properties. Its ability to resist nitric acid attack permits its use in specific chemical applications but automotive trim and appliance components represents its largest fields of application.
Grade 430F is the free-machining version of this grade, available in bar form for use in automatic screw machines. Grade 434 is the molybdenum bearing version of Grade 430 and has the same useful combination of properties. Its molybdenum addition improves corrosion resistance.
These properties for 430 are specified for flat rolled product (plate, sheet and coil) in ASTM A240/A240M. Similar but not necessarily identical properties are specified for other products such as forgings and bar in their respective specifications. Properties of Grade 430F are specified for bar in ASTM A582.