Pre-Painted Galvanized Steel Coil

Pre-painted galvanized steel coil is a semi-finished industrial material consisting of a galvanized steel substrate with a factory-applied paint or polymer coating. It serves as a key raw material in metal furniture manufacturing, providing both corrosion protection and a decorative finish in a single material. This product streamlines production by eliminating separate painting processes, reducing VOC emissions, and ensuring consistent finish quality. In B2B supply chains, it is supplied in coil form for efficient storage, transportation, and feeding into roll-forming or stamping equipment.

The galvanized coating provides sacrificial corrosion protection through electrochemical action, while the factory-applied paint or polymer layers create a durable, uniform surface. The product is available in a range of specifications, including steel thickness from 0.3 to 2.0 mm, coil width from 600 to 1250 mm, and coil weight from 3 to 10 kg (likely per meter or as specified). Coating thickness per side is 20–40 μm, with surface hardness of HB 60–80, gloss level of 20–80 GU, and color consistency within ΔE ≤ 1.0. Mechanical properties include tensile strength of 270–500 MPa, yield strength of 140–350 MPa, and elongation of 20–40% (A50 gauge length). Bendability is 0–2T without cracking, impact resistance is ≥ 9 J, and salt spray resistance is ≥ 500 hours. Operating temperature range is -20 to 80 °C.

These values are reference ranges based on standards such as GB/T 12754, GB/T 6739, GB/T 11186.2, GB/T 9754, GB/T 13448, GB/T 1732, and GB/T 10125. Actual values must be verified with the supplier for the specific grade and application. The product is intended for use in metal furniture components such as frames, shelves, and panels, where corrosion resistance and aesthetics are required. When selecting, consider the required mechanical properties, coating performance, and environmental conditions. Verify that the supplied coil meets the specified standards and test methods. Maintenance signals include coating degradation, corrosion creep, or color change. Failure boundaries include exposure beyond the specified temperature range or salt spray limits.

Zinc galvanization provides sacrificial corrosion protection through electrochemical action, where zinc corrodes preferentially to protect the steel substrate. The factory-applied paint or polymer coating creates a durable, uniform decorative surface through controlled application and curing processes. This dual-layer system ensures long-term performance in indoor furniture applications, with the coating acting as a barrier against moisture and chemicals, while the zinc layer offers cathodic protection at cut edges and scratches.