1.What are the basic definitions and standards of SPCD?
Standards: Primarily based on Japanese Industrial Standard JIS G 3141, "Cold-rolled Carbon Steel Sheet and Strip," which is also widely referenced by relevant industries both internationally and domestically (for example, some Chinese companies use this standard in their production).
Material Properties: This steel is low-carbon, typically with a low carbon content (typically ≤0.15%) and contains no intentionally added alloying elements. It primarily consists of iron and carbon, and exhibits excellent cold-rolling properties.
2.What are the mechanical properties of SPCD?
Tensile Strength: 270-370 MPa
Yield Strength: 130-250 MPa (varies depending on rolling conditions)
Elongation: ≥28% (thickness ≤ 0.7mm), ≥30% (thickness > 0.7mm)
Hardness: HRB 60-80 (cold-rolled, hardness is higher before annealing, can be reduced after annealing)
3.What are the common surface conditions and treatments of SPCD?
Surface Characteristics: The cold rolling process results in a smooth, flat surface with high precision and low roughness (typically Ra ≤ 1.6μm), no scale, and excellent appearance.
Common Surface Treatments:
Untreated: Used directly, the surface is oiled (rust-proof oil), requiring careful storage to prevent rust.
Galvanized: Electroplating or hot-dip galvanizing enhances corrosion resistance (e.g., SPCC galvanized steel can be used in humid environments).
Painted/Laminated: Serves as a base material for color-coated steel sheets, or directly laminated for surface protection.
4.What are the performance characteristics and applicable scenarios of SPCD?
Core Advantages:
Smooth surface and high dimensional accuracy (thickness tolerance can be controlled to ±0.01mm), suitable for applications requiring high aesthetics and precision.
Excellent plasticity allows for complex stamping (such as deep drawing and stretching), bending, welding, and other processes.
Affordable price, superior cost-performance compared to alloy cold-rolled steel, suitable for mass production.
Main Applications:
Home Appliance Industry: Refrigerator, washing machine, and air conditioner housings and internal components (such as panels and partitions).
Automotive Industry: Non-load-bearing components such as door trim panels and instrument panel brackets.
Hardware: Stamped parts (such as brackets and connectors), stationery (such as folders), and metal containers (such as packaging boxes).
Architectural Decoration: Small metal components and decorative panels (requiring subsequent painting or galvanizing for corrosion resistance).
5.What are the precautions?
Corrosion Resistance: SPCC is bare steel and prone to rust. It requires anti-rust oil during storage and, depending on the environment, requires anti-corrosion treatment such as galvanizing or painting before use.
Processing Limitations: Cold-rolled steel has a higher hardness, so annealing may be required before complex deep drawing processes (for example, annealed SPCC steel exhibits improved plasticity).
Purchasing Identification: When purchasing, the surface condition (e.g., whether oiled), dimensional tolerance, and whether annealing is required should be clearly specified to avoid misuse.