HPB400 is a Chinese national standard hot-rolled plain round concrete reinforcement rebar with a specified yield strength of 400MPa, outperforming HPB300 in mechanical strength while retaining superior plasticity and ductility. It features excellent weldability and cold workability for easy on-site processing, and good bonding performance with concrete for structural stability. Available in a full range of standard diameters, it has stable mechanical properties, reliable quality and high cost-effectiveness, serving as a mainstream and core reinforcement material for various modern construction engineering projects.