ASTM A588 steel is known for its atmospheric corrosion resistance thanks to a natural patina of rust that forms when exposed to outdoor weather conditions. ASTM A588 steel is available in 3 grades, A, B, and K.
ASTM A588 Grades A and B both have good material machinability.
ASTM A588 steel was developed primarily for industries requiring outdoor structural steel solutions, wherever there is a need for a combination of lighter weight, higher durability, and exceptional corrosion resistance.
The biggest advantage to ASTM A588 high strength low alloy steel is its atmospheric corrosion resistance for which it was specially formulated. It is substantially better than other structural steels like ASTM A36 or ASTM A572.
ASTM A588 VS ASTM A572
ASTM A588 welds similar to low carbon steels like ASTM A36 and ASTM A572. Due to A588's specific coloring, you will need to consider color matching when welding.