The 303 grade stainless steel has the best machinability among the Austenitic stainless steel grades. Like the 304 and 316 grades, it is one of the most widely used stainless steel grades around the world. The reason of better machinability is the sulfur inclusion of the 303 grade. However, although the sulfur increases its machinability; it also decreases the corrosion resistance of the material. Therefore the 303 grade has much lower corrosion resistance than 304 grade.
The production of 303 is more difficult than other grades. The chemical composition’s balance and the homogenous distribution of the elements are very important. The homogenous distribution of the alloys is adjusted during annealing.
With a careful and correct annealing process, the end results of higher machinability and mechanical properties will be obtained. However a poor annealing process means the material may cause difficulties in machining.
Rating of Grade Properties
Note: Rating is done over 5 points.
Bolt manufacturing, screw and bolt production, automotive gears, fasteners, food processing, electronic equipments.