What is the corrosion resistance of SGCC coils?
Answer: SGCC coils have excellent corrosion resistance. Their hot-dip galvanized layer forms a physical barrier, preventing corrosive media such as water and oxygen from coming into direct contact with the steel. When the zinc layer is damaged, the zinc preferentially corrodes through electrochemical reactions, protecting the steel. The rust-proof effect generally lasts for 30-50 years.
Why do SGCC coils have such good corrosion resistance?
Answer: First, the hot-dip galvanized layer provides a physical barrier, preventing corrosive media from coming into contact with the substrate. Second, zinc is more chemically active than iron. When the zinc layer is damaged, zinc preferentially oxidizes as the anode, protecting the iron substrate, which acts as the cathode. This electrochemical protection is also known as sacrificial anode protection.
What surface treatments are available for SGCC coils?
Answer: Common surface treatments include passivation (C), phosphating (P), oiling (O), and anti-fingerprint coating (N).
What processing operations are suitable for SGCC coils?
Answer: SGCC coils are suitable for processing operations such as welding, stamping, bending, and cutting. The cold rolling process results in a smooth surface and uniform thickness, offering excellent workability.
What precautions should be taken when bending SGCC coils?
Answer: When bending, be careful not to overly narrow the bending radius to prevent cracking or loss of the zinc layer. Appropriate bending equipment and molds should be selected based on the thickness and strength of the sheet.