A low-carbon mild steel with 0.06-0.12% carbon content, featuring excellent ductility and weldability but limited strength. Suitable Processes‌: Cold forming, bending, welding (all methods), stamping. Applications‌: Wire products, nails, fencing, and light structural frames.

Mild structural steel with 0.09-0.15% carbon, offering improved strength over Q195 while retaining good formability. Suitable Processes‌: Hot rolling, welding, shearing, riveting. Applications‌: Rebar, pipes, sheet metal components, and agricultural equipment.

China's most common structural steel (0.12-0.20% C) with balanced strength and plasticity, equivalent to ASTM A36. Suitable Processes‌: Hot rolling, forging, arc welding, machining. Applications‌: Building frameworks, bridges, truck chassis, and machinery bases.

Medium-carbon structural steel (0.18-0.28% C) with higher yield strength than Q235 but reduced weldability. Suitable Processes‌: Hot working, limited welding (preheat required), machining. Applications‌: Axles, couplings, and stressed mechanical parts.

High-strength carbon steel (0.28-0.38% C) requiring controlled processing due to carbon sensitivity. Suitable Processes‌: Hot forging, normalizing, precision machining. Applications‌: Gears, shafts, and high-load structural components.

Ultra-low-carbon steel (≤0.05% C) with superior deep-drawing characteristics for precision forming. Suitable Processes‌: Cold stamping, deep drawing, spinning. Applications‌: Automotive body panels, fuel tanks, and electrical appliance casings.

Free-cutting variant of 10-carbon steel with added sulfur/phosphorus for enhanced machinability. Suitable Processes‌: Turning, drilling, automatic screw machining. Applications‌: Fasteners, bushings, and mass-produced small precision parts.

Low-carbon engineering steel (0.17-0.23% C) offering optimal balance between machinability and case-hardening potential. Suitable Processes‌: Carburizing, cold heading, CNC machining. Applications‌: Camshafts, pins, and surface-hardened wear components.

Medium-carbon workhorse steel (0.42-0.50% C) widely used for quench-tempering heat treatment. Suitable Processes‌: Quenching & tempering, induction hardening, grinding. Applications‌: Crankshafts, bolts, and high-strength mechanical linkages

Chromium-alloyed steel (0.37-0.44% C + 0.8-1.1% Cr) with enhanced hardenability over plain carbon steels. Suitable Processes‌: Oil quenching, tempering, thread rolling. Applications‌: High-stress bolts, hydraulic press columns, and gear shafts.

Chromium-molybdenum alloy steel (0.32-0.40% C) for high-temperature strength and fatigue resistance. Suitable Processes‌: Vacuum heat treatment, precision forging, shot peening. Applications‌: Aircraft landing gear, turbine shafts, and high-pressure fittings.

Premium alloy steel (0.38-0.45% C + Cr-Mo) delivering exceptional toughness under extreme loads. Suitable Processes‌: Ultrasonic testing, isothermal quenching, finish grinding. Applications‌: Drill collars, military vehicle axles, and heavy-duty gears. Material Selection Tip‌: The Q-series steels prioritize weldability/formability, while numbered grades (e.g., 45#) focus on mechanical performance. Alloy steels (Cr/Mo) excel in fatigue-critical applications.