What are the core chemical components of SPCC sheet?

Q: What are the core chemical components of SPCC sheet? What are the functions of each component?
A: Main components and their functions: ① Carbon (C ≤ 0.15%): Ensures basic strength; too high a content reduces formability; ② Manganese (Mn ≤ 0.60%): Increases strength and improves rolling properties; ③ Phosphorus (P ≤ 0.035%) and Sulfur (S ≤ 0.035%): Harmful impurities, controlled at low levels to prevent embrittlement; ④ Iron (Fe): Matrix component, accounting for over 99%.
Q: What are the standard ranges for yield strength and tensile strength of SPCC sheet?
A: According to GB/T 11253: Yield strength is 230-300 MPa, and tensile strength is 310-430 MPa. Specific values ​​fluctuate slightly due to rolling accuracy (such as thickness). Thinner gauges (≤ 1.0 mm) have slightly higher strength, while thicker gauges (≥ 3.0 mm) have slightly lower strength.
Q: What is the required elongation for SPCC sheet? How does this affect processing?
A: The standard requires an elongation of ≥28% (1.0-2.0mm thickness). The higher the elongation, the less likely it is to crack during bending and stamping. If deep drawing is required, SPCC's elongation is insufficient, so SPCD/SPCE (elongation ≥34%) should be used.
Q: What is the typical hardness of SPCC sheet? What hardness scale is commonly used to measure it?
A: The hardness range is HV 80-110 (Vickers hardness) or HRB 60-80 (Brinell hardness). Vickers hardness (HV) is commonly used for testing. Because the sheet surface is hard and thin after cold rolling, Vickers hardness is more suitable for testing small areas.
Q: How does SPCC sheet age? Does it harden over time? A: SPCC is a "non-aging steel". When stored at room temperature for 1-3 months, the strength and hardness change very little (≤5%). There is no need to worry about "aging hardening" causing cracking during processing. If long-term storage (>6 months) is required, it is recommended to apply anti-rust oil to prevent oxidation from affecting performance.