What is grade A36 steel?
ASTM A36 is a low carbon steel. Low carbon steels are classified by having less than 0.3% carbon by weight. This allows A36 steel to be easily machined, welded, and formed, making it extremely useful as a general-purpose steel. The low carbon also prevents heat treatment from having much of an effect on A36 steel. A36 steel usually has small amounts of other alloying elements as well, including manganese, sulfur, phosphorus, and silicon. These alloying elements are added to give A36 steel its desired chemical and mechanical properties. Since A36 does not contain large amounts of nickel or chromium, it does not have excellent corrosion resistance.

ASTM A36 steel plates will have a lot of equivalent materials, such as A283C, FE360B, E24-2, Chinese material Q235B, Japan material SS400 and SM400A, European material EN S235JR, Germany material DIN ST37-2, etc. Those equivalent materials have little difference in chemical composition and mechanical properties, below are some of the grades comparison for your reference: