303L Stainless Steel Round Bar

Designed for use in aircraft parts, valves, valve trims, screw machine products, bolts, screws, and architectural applications.


The 303L stainless steel round bar is a widely-used metal in aviation, industrial and architectural applications. It is a chromium-nickel metal that has been alloyed with sulfur. Because of its integration with sulfur, it is the most readily machinable non-magnetic stainless steel. The presence of sulfur also makes it not as tough as the other chromium-nickel metals like 304 and 316, but it is still strong. It also helps to make the steel more corrosion-resistant, however, it is less resistant to corrosion than alloy 304.

The applications used for alloy 303 include screws, nuts, bolts, shafts, gears and aircraft fittings. It’s ideal for use on moving parts. 303 stainless steel round bars have a great scale resistance when continuously serviced in temperatures up to 1600 degrees Fahrenheit. To increase tensile strength and hardness, cold working can be used. Note that when cold working, slight magnetism is usually found.

This grade of stainless steel is exclusively used for parts that need to be polished, machined or ground. It’s ideal for parts that need good resistance to corrosion and non-galling and non-seizing properties (such as with moving parts). The machinability rating for this alloy is 78 percent of B1112. The average cutting speed of this metal is 130 ft. per minute. The weld-ability of 303 alloys is low to fair, but can be forged when placed in heat between 2100 and 2350 degrees Fahrenheit. It’s best not to use temperatures below 1700 degrees Fahrenheit to forge 303 stainless steel.

Heat treatment cannot be used for 303 alloys. For annealing, a range between 1850 and 2050 degrees Fahrenheit should be used. It cools fairly quickly. All that’s needed is air for the lighter sections, but for the heavier sections, water can be used for cooling.

The size ranges for this product include .1563-6 inches diameter and up to 144 inches long.