UNS K02600 A36 carbon steel is a low-carbon mild structural steel, the most widely used general-purpose carbon structural steel in North America and global industrial fields. It features excellent weldability, good formability, moderate structural strength and outstanding cost performance, which is widely used in structural engineering, general machinery manufacturing, pipe fittings,industrial brackets, shipbuilding and other conventional industrial applications.
Machinability
Carbon steel grade UNS K02600 S235JR A36 has excellent machinability characteristics that are superior to most high-alloy steels and austenitic stainless steels; it exhibits stable cutting performance, low work hardening tendency, and good chip breaking performance under conventional processing conditions. It is recommended that standard high-speed steel or uncoated/coated carbide tooling be used, and conventional cutting speeds and feeds can be applied to achieve efficient processing.
Forming
Carbon steel grade UNS K02600 S235JR A36 can be formed using all conventional cold and hot forming methods widely applied for low-carbon structural steels. It has excellent ductility, which allows it to complete cold bending, stamping, roll forming and other cold forming processes without additional preheating at room temperature. Hot forming and forging can be done at 950-1200°C (1742-2192°F), with no strict requirements for post-forming cooling methods under general working conditions.
Welding
Welding of carbon steel grade UNS K02600 S235JR A36 can be performed using all traditional fusion welding processes, including SMAW, GMAW, SAW, GTAW and other common welding methods. Recommended filler metal should match the base material strength, commonly used grades include AWS E7018, E7016 for shielded metal arc welding, and ER70S-6 for gas metal arc welding. Preheating is generally not required for thin-walled parts at room temperature; for thick-walled parts (≥25mm) or in low-temperature environments, preheating to 50-150°C is recommended to avoid cold cracks.
Heat Treatment
Final stress relief annealing process performed for welded structural parts or precision formed parts, is done at 595-650°C
(1100-1200°F), which is followed by air cooling or furnace cooling as required. Normalizing treatment to refine grain and
homogenize structure can be done at 870-925°C (1600-1700°F). This low-carbon steel cannot be hardened by conventional quenching and tempering heat treatment, and its strength is mainly adjusted by controlled rolling and cold working.