ASTM A304/304L Stainless Steel Mechanical Tubing dual certified stainless is a very low carbon "18-8" austenitic chromium-nickel steel with good corrosion resistance and superior resistance to intergranular corrosion following welding or stress relieving. The low carbon content limits the formation of harmful carbides to such an extent that this grade may be safely used for most operations of welded construction, and where the service temperature is limited to 800°F. It is non-magnetic in the annealed condition and not hardenable by heat treatment. Both hardness and tensile strength can be increased by cold working, which may cause slight magnetism. The dual certified 304/304L meets specifications for both 304 and 304L stainless steel and may be interchanged and used safely for either grade's application.

304/304L stainless generally conforms to ASTM A276, ASTM A479, AMS 5639.

304/304L stainless plate generally conforms to ASTM A167, ASTM A240, AMS 5513, ASME SA240.

ASTM A304/304L Stainless Steel Mechanical Tubing conforms to Welded: ASTM A249, ASTM A269, ASME SA249, ASME SA269, Seamless: ASTM A269, ASTM A514, ASTM A511, ASME SA269 Cold Drawn and Seamless: ASTM A213, ASME SA213 Square and Rectangle Tube: ASTM A554 Stainless Steel Pipe: ASTM A312 (seamless), A312 (welded), A376 (welded).

ASTM A304/304L Stainless Steel Mechanical Tubing General Information about 304 / 304L:

APPLICATIONS

304 / 304L is used almost exclusively for parts requiring machining, welding, grinding, or polishing where good corrosion resistance is also required. It is a good general all-purpose stainless grade. It is good in corrosive environments as in paper and chemical industries and cryogenic services and used where corrosion resistance and good mechanical properties are primary requirements. 304/304L is widely accepted in such industries as dairy, beverage, and other food industries where the highest degree of sanitation and cleanliness is of prime importance. Parts for handling acetic, nitric, and citric acids, organic and inorganic chemicals, dyestuffs, crude and refined oils, etc. are fabricated from this material. Because of its lack of magnetism, it is highly desirable for instruments. It is also widely used for architectural trim. 304 plate is used in applications where corrosion resistance is required, but elevated temperatures are not involved. 304/304L finds particular use in applications requiring welding. 304/304L has good drawing, forming, and stamping properties. 304/304L angles are used extensively for brackets, bracing, shelves, structural supports, etc.

MACHINING AND WELDING:

A304 / 304L machinability is rated at 45% of B1112. Average cutting speed is75 ft/min. It is easily welded by all commercial processes except forge or hammer welding. The resultant weld has good toughness and ductility. Annealing is recommended after forging to maintain maximum corrosion resistance. 304/304L can be forged between 2100° - 2350°F. Do not forge below 1700°F.

HEAT TREATING - Forging, Normalizing, and Annealing:

304 / 304L is not hardenable by heat treatment. Cold working increases tensile strength and hardness. Annealing range is between 1850° and 2050°F. Cool rapidly. Water should be used for heavier sections; air for lighter sections. The stress relieving range is between 400° and 750°F.