This specification covers high-strength, low-alloy, hotand cold-rolled sheet and strip in cut lengths or coils, intended for use in structural and miscellaneous purposes, where savings in weight or added durability are important. These steels have enhanced atmospheric corrosion resistance and are supplied in two types: Type 2 contains 0.20 % minimum copper based on cast or heat analysis (0.18 % minimum Cu for product check). Type 4 contains additional alloying elements and provides a level of corrosion resistance substantially better than that of carbon steels with or without copper addition (Note 1). When properly exposed to the atmosphere, Type 4 steel can be used bare (unpainted) for many applications.
| Composition, max, % | ||
|---|---|---|
| Cast or Heat (Formerly Ladle) Analysis | Product Check, or Verification Analysis | |
| CarbonA | 0.22 | 0.26 |
| Manganese | 1.25 | 1.30 |
| Sulfur | 0.04 | 0.06 |
A. For compositions with a maximum carbon content of 0.15 % on heat or cast analysis, the maximum limit for manganese on heat or cast analysis may be increased to 1.40 % (with product analysis limits of 0.19 % carbon and 1.45 % manganese).
| As-Rolled | Annealed or Normalized | |
|---|---|---|
| Tensile strength, min ksi (MPa) | 70 [480] | 65 [450] |
| Yield strength, min, ksi (MPa) | 50 [340] | 45 [310] |
| Elongation in 2 in. or 50 mm, min, % | 22 | 22 |
A. For coil products, testing by the producer is limited to the end of the coil. Mechanical properties throughout the coil shall comply with the minimum values specified.
| Cut Lengths and Coils | |
|---|---|
| Tensile strength, min ksi (MPa) | 65 [450] |
| Yield strength, min, ksi (MPa) | 45 [310] |
| Elongation in 2 in. or 50 mm, min, % | 22A |
A. 0.0448 in. [1.1 mm] and under in thickness—20 %.