What is alloy structural steel?

Alloy structural steel is carbon-based structural metal with intentional additions of chromium, nickel, molybdenum, manganese and silicon, designed to bear static and dynamic heavy loads in machinery and engineering. Different from plain carbon steel, its chemical composition is precisely calibrated to improve hardenability, low-temperature toughness and fatigue resistance. After quenching and tempering heat treatment, it gains matched high strength and ductility without excessive brittleness. It is produced into bars, forgings, plates and seamless pipes, acting as the primary load-bearing material for most medium and heavy industrial mechanical assemblies with balanced cost and mechanical performance.