Q:What is the production process of SGCC?
A:Substrate preparation: Cold rolled steel sheet (SPCC) is used as the substrate, the thickness range is usually 0.3-6.0mm, the surface flatness is high and the mechanical properties are stable.
Hot dip galvanizing process: After pickling and plating treatment, the substrate is immersed in molten zinc liquid at about 450-500℃, and zinc and iron react metallurgically to form a zinc-iron alloy layer and a pure zinc layer.
Q:What is the common coating weight of SGCC?
A:Common coating weights are Z100 (100g/m²) and Z275 (275g/m²), corresponding to double-sided coating thicknesses of about 14μm to 38μm, much thicker than electrogalvanized sheet (SECC)
Q:What are SGCC's competitive advantages?
A:Cost advantage: Although the single purchase cost is 10%-20% higher than SECC, the long-term maintenance cost is extremely low, and the comprehensive cost performance is outstanding.
Processing adaptability:
Welding: The current needs to be controlled to avoid evaporation of the zinc layer and cause pores. It is recommended to use silicon-containing welding wire.
Coating: The surface of small zinc flowers or smooth zinc flowers can be directly sprayed with polyester or fluorocarbon paint, and the adhesion is better than SECC.
Environmental protection trend: The chromium-free passivation technology is mature, and the export products can meet the EU REACH regulations and avoid trade barriers.
Q:How many types of zinc spangles does SGCC have?
A:Normal zinc spangle (Z): Hexagonal zinc spangle is formed by natural cooling, which is low in cost and suitable for building roofs, guardrails, etc. Small zinc spangle (X): The growth of zinc spangle is inhibited by rapid cooling, and the surface is more delicate, which is suitable for painting or scenes that require beauty (such as home appliance shells). Polished zinc spangle (GZ): The zinc spangle is eliminated by flat rolling, and the surface roughness is low, which is used for deep drawing parts (such as automobile fuel tanks).
Q:What is the industry development trend of SGCC?
A:1. Environmental upgrade: Chromium-free passivation technology (such as molybdate and silane treatment) gradually replaces traditional chromate and becomes the mainstream.
2. Coating alloying: New coating materials such as aluminum zinc plating (SGLC) and zinc nickel plating (SGND) have emerged, with corrosion resistance increased by 3-5 times and costs increased by 15%-30%.
3. Intelligent production: The continuous hot-dip galvanizing line introduces an AI visual inspection system to monitor the uniformity of the zinc layer in real time and reduce the scrap rate to less than 1%.