303 stainless steel is the most readily machineable of all the austenitic grades of stainless steel.
303 stainless steel owes its machineable nature to the presence of Sulphur in the composition. However, it should be noted that the Sulphur also decreases the corrosion resistance of the steel and slightly lowers its toughness. The toughness is still excellent as with other austenitic grades. AISI 304 stainless steel offer higher corrosion resistance than 303.
