High strength low alloy steel (HSLA) is a type of alloy steel that provides better mechanical properties or greater resistance to corrosion than carbon steel. High strength low alloy steel (HSLA) offer better environmental corrosion resistance and are more robust than convention carbon steel. GB/T16270:SM490(A,B,C),SM490Y(A,B) SM520(B,C Products / Alloy Steel Plates__Steel SupplierLow Alloy High Strength Steel Boiler Steel Plate Alloy Steel Plates GB/T16270 Alloy Steel Plates in quenched and tempered condition. Q460C. Q460D. Q460E. Q460F. Q500C. Q500D. Q500E. Q500F. Q550C. HG980D High Strength Steel plate Henangang iron and steel ,ltd is specialized in high strength plate HG60 HG.