The Power of 3

Benefits of Stainless Steel

 

The many unique values provided by stainless steel make it a powerful candidate in materials selection. Engineers, specifiers, and designers often underestimate or overlook these values because of what is viewed as the higher initial cost of stainless steel. However, over the total life of a project, stainless is often the best value option. (The Stainless Steel Information Center)

Type 301 (UNS S30100)

 

Type 301 is an austenitic chromium-nickel stainless steel that is available in the annealed and cold worked conditions. In the annealed condition, Type 301 offers the highest level of stretch formability of any stainless steel and in the heavily cold worked condition offers the highest strength level of any 300 series stainless steel. Type 301 is non-magnetic in the annealed condition but becomes magnetic as a result of cold working.

 

Type 301 is corrosion resistant in many environments, but the corrosion properties are less than that of 304/304L stainless steel. The susceptibility to carbide precipitation during welding restricts the use of Type 301 in some applications and 304L is used because of its lower carbon content for welded applications.

 

APPLICATIONS:

• Aircraft structural parts
• Automotive wheel covers (rims), wiper blade clips and holders
• Trailer bodies
• Stove element clips
• Utensils and toaster springs
• Roof drainage products
• Conveyor belts

Type 302 (UNS S30200)

 

Type 302 is an austenitic chromium-nickel stainless steel that is available in the annealed and cold worked conditions. Type 302 is a higher carbon, earlier version of Type 304 stainless steel, and many 302 applications have switched to Type 304 with the improvements in melting technology. Type 302 is non-magnetic in the annealed condition but becomes magnetic as a result of cold working.

 

Type 302 is corrosion resistant in many environments, and the corrosion properties are similar to that of 304/304L stainless steel. The susceptibility to carbide precipitation during welding restricts the use of Type 302 in some applications and 304L is used because of its lower carbon content for welded applications.

 

APPLICATIONS:
• Food and beverage industry
• Sanitary or cryogenic applications
• Wire forming
• Stamping
• Spinning
• Washers, springs, screens, and cables

Type 304 (S30400), Type 304L (S30403)

 

Type 304/304L is the modern version of “18-8” stainless steel containing approximately 18% chromium and 8% nickel and is the most commonly specified stainless steel used throughout the world. Type 304/304L is a versatile, general purpose stainless steel with good resistance to atmospheric corrosion, and to many chemicals and food and beverages. These grades can be specified in the annealed condition where they have very good formability. Higher nickel versions can be specified to enhance multi-stage deep drawing characteristics. Higher strength, cold-worked conditions can also be specified for Type 304/304L for spring type applications. Type 304/304L is non-magnetic in the annealed condition but may become slightly magnetic as a result of cold working.

 

Type 304L can be dual certified as 304 when the composition meets the lower carbon limit of 304L and the slightly higher strength levels of 304. Type 304L should be specified for welded applications as the low carbon version eliminates chromium carbide precipitation and enhances the corrosion resistance in the as-welded condition.

 

APPLICATIONS:
• Heat exchangers
• Automotive and aerospace structural use
• Food processing equipment
• Kitchen benches, sinks, troughs, equipment and appliances
• Fasteners in the saltwater marine environment
• Chemical containers
• Architectural trim and molding
• Woven or welded screens for mining and water filtration

Type 305 (UNS S30500)

 

Type 305 is a chromium-nickel austenitic stainless steel with a low rate of work hardening due to the elevated nickel content. This low rate of work hardening makes this grade well suited for multi-stage deep drawing applications without process annealing where 304/304L may suffer from cracking issues. Type 305 is non-magnetic in the annealed and cold worked conditions and has corrosion resistance similar to 304/304L stainless steel.

 

APPLICATIONS:

• Kitchen appliances and utensils
• Electronic enclosure applications
• Metal spinning or deep drawn parts
• Tank covers
• Dairy industry

Type 309 (UNS S30900)

 

Type 309 is a high-temperature chromium-nickel austenitic stainless steel that resists oxidation at temperatures up to 1900˚F in dry air at a constant temperature. Under thermal cycling conditions, this grade resists oxidation up to a temperature of approximately 1850˚F. Type 309 has good sulfidation resistance but low resistance to carburization and should not be used in highly carburizing atmospheres. Type 309 is non-magnetic in the annealed and cold worked conditions and is as resistant to corrosion as Type 304/304L.

 

APPLICATIONS:
• Heating elements
• Furnace parts

Type 310 (UNS S31000), Type 310S (UNS S31008)

Type 310 is a high-temperature chromium-nickel austenitic stainless steel with high creep strength that resists oxidation at temperatures up to 2000˚F in dry air. Type 310 forms a tenacious scale at high temperature and is resistant to spalling and performs better than Type 309 in thermal cycling applications. Type 310 has good sulfidation resistance and good resistance to carburization in moderately carburizing atmospheres. Type 310 is non-magnetic in the annealed and cold worked conditions and is as resistant to corrosion as Type 304/304L. Type 310S is the low carbon version of Type 310 and is utilized for ease of fabrication due to its better formability and weldability.

 

APPLICATIONS:
• Heat exchangers
• Combustion tubes and fire box sheets
• Oil Burner Parts
• Welding filler wire and electrodes
• Annealing covers and furnace parts

Type 316 (UNS S31600), Type 316L (UNS S31603)

 

Type 316/316L is a chromium-nickel austenitic stainless steel containing molybdenum. The molybdenum addition enhances the corrosion resistance over that of 304/304L in halide environments as well as in reducing acids such as sulfuric and phosphoric acid. Type 316L can be dual certified as 316 when the composition meets the lower carbon limit of 316L and the slightly higher strength levels of 316. Type 316L should be specified for welded applications as the low carbon version eliminates chromium carbide precipitation and enhances the corrosion resistance in the as-welded condition.

 

Type 316/316L resists atmospheric corrosion as well as in moderately oxidizing environments. It also resists corrosion in marine atmospheres and has excellent resistance to intergranular corrosion in the as-welded condition. Type 316/316L has excellent strength and toughness at cryogenic temperatures. Type 316/316L is non-magnetic in the annealed condition but may become slightly magnetic as a result of severe cold working.

 

APPLICATIONS:

• Heat exchangers
• Paper and pulp machinery
• Pollution control equipment
• Chemical processing equipment
• Food preparation equipment
• Pharmaceutical industry
• Boat fittings, valves, and pump trim
• Condensers, evaporators, and tanks

Type 321 (UNS S32100)

 

Type 321 is a titanium stabilized chromium-nickel austenitic stainless steel with corrosion resistance similar to 304/304L. This grade is typically used in the 800-1500˚F temperature range where it is stabilized against chromium carbide precipitation by the addition of titanium, which results in the precipitation of titanium carbides. Type 321 has excellent intergranular corrosion resistance after exposure to this temperature range, and this grade resists oxidation up to 1500˚F and has higher creep and stress rupture properties than 304/304L. It also possesses good low-temperature toughness and is non-magnetic in the annealed condition.

 

APPLICATIONS:
• Aerospace – piston engine manifolds
• Chemical processing industry and thermal oxidizers
• Expansion or movement joints
• Food processing equipment
• Polythionic acid service

Type 347 (UNS S34700)

 

Type 347 is a niobium stabilized chromium-nickel austenitic stainless steel with corrosion resistance similar to 304/304L. This grade is typically used in the 800-1500˚F temperature range where it is stabilized against chromium carbide precipitation by the addition of niobium, which results in the precipitation of niobium carbides. Type 347 has excellent intergranular corrosion resistance after exposure to this temperature range, and this grade resists oxidation up to 1500˚F and has higher creep and stress rupture properties than 304/304L. It also possesses good low-temperature toughness and is non-magnetic in the annealed condition.

 

APPLICATIONS:
• High-temperature chemical processes and general refinery piping
• Heat exchanger tubes and high-pressure steam pipes
• Superheaters and boiler tubes
• Heavy duty exhaust systems

For more information on how stainless steel may be ideal for your project, contact one of our knowledgeable sales representatives.