How to handle excessive springback when bending SPCC sheets?
A: Optimize the bending die design by increasing the die radius; appropriately increase the bending pressure and extend the holding time; pre-treat the sheet material to eliminate internal residual stress.
Why are SPCC sheets prone to rust?
A: As low-carbon cold-rolled steel, it lacks a natural, dense protective film on its surface. In humid or corrosive environments, it readily oxidizes and forms rust.
How to improve the corrosion resistance of SPCC sheets?
A: Electro-galvanizing, hot-dip galvanizing, color coating, or phosphating can be applied. In special cases, chromate passivation can be used to form a Cr₂O₃ protective film. Alloyed hot-dip galvanizing can also balance corrosion resistance and weldability.
How effective is the corrosion resistance of electro-galvanized SPCC sheets?
A: With an electro-galvanized layer thickness of 3-20μm and a zinc coating thickness of 30-90g/m², it can resist neutral salt spray corrosion for over 72 hours.
How is the weldability of SPCC plates?
Answer: Excellent weldability. The low carbon content results in a heat-affected zone hardness ≤180HV, a carbon equivalent of no more than 0.28%, and a weld strength coefficient of over 0.9.