: An austenitic free-machining stainless steel. The standard 18-8 stainless steels are more difficult to turn, mill and drill which restricts their use when considerable machining is required. The additional sulfur present in 303 assists in breaking up turnings which reduces drag on the cutting tool. This permits greater machining speed and tends to produce smoother machined finishes which in turn lowers production costs.
This material is not as resistant to general corrosion as is 304. It tends to form a rust film more readily in moist atmospheres and is very susceptible to pitting or localized corrosion in solutions of chlorides, iodides, or bromides. Under relatively dry conditions or in mildly corrosive environments, 303 resists rust. It also has good resistance to oxidation up to 1700°F. 303 is not recommended for vessels containing gases or liquids under high pressure. It is available as hot rolled, annealed and pickled (HRAP) or hot rolled, annealed only (HRA) plate.
Utilized wherever a combination of good corrosion resistance and considerable machining is required for a part. Applications include aircraft fittings, computer motor holder rings, bushings, fittings, pump and valve parts, screw machine products, shafts and other parts requiring extensive machining.
: Austenitic Cr-Ni stainless steel. Better corrosion resistance than Type 302. High ductility, excellent drawing, forming, and spinning properties. Essentially non-magnetic, becomes slightly magnetic when cold worked. Low carbon content means less carbide precipitation in the heat-affected zone during welding and a lower susceptibility to intergranular corrosion.
Applications: beer kegs, bellows, chemical equipment, coal hopper linings, cooking equipment, cooling coils, cryogenic vessels, dairy equipment, evaporators, flatware utensils, feedwater tubing, flexible metal hose, food processing equipment, hospital surgical equipment, hypodermic needles, kitchen sinks, marine equipment and fasteners, nuclear vessels, oil well filter screens, refrigeration equipment, paper industry, pots and pans, pressure vessels, sanitary fittings, valves, shipping drums, spinning, still tubes, textile dyeing equipment, tubing.
Corrosion Resistance: resists most oxidizing acids and salt spray.
: Stainless Steel 316 contains molybdenum. This addition increases general corrosion resistance, improves resistance to pitting from chloride ion solutions, and provides increased strength at elevated temperatures.