1. Core Definition & Standard Compliance

1.1 Fundamental Overview

SPCC cold rolled steel is a non-alloy, low-carbon cold-rolled steel produced via precision cold rolling after hot rolling, pickling, and annealing. Its naming follows JIS G 3141 conventions:

• S: Steel (carbon steel);

• P: Plate (sheet/plate product);

• C: Cold (cold-rolled);

• C: Commercial quality (general-purpose grade).

• Key Equivalents: EN 10130 DC01, ASTM A1008 CS Type B, GB/T 716 Q195/Q215, DIN 1613 St12.

1.2 Core Standards

• Primary Standard: JIS G 3141 (Japanese Industrial Standard for cold-rolled carbon steel sheets and strips);

• Complementary Standards: ISO 3574 (global cold-rolled steel standard), EN 10130 (European equivalent), and ASTM A1008 (American standard);

• Quality Grades: Classified by surface finish and processing suitability, with common variants including SPCC-SD (standard surface), SPCC-1D (matte finish), SPCC-2D (dull finish), and SPCC-2B (bright finish).

2. Chemical Composition

SPCC’s low-carbon formulation is optimized for formability and machining, with strict control over impurity content to ensure processing stability. Chemical composition (mass fraction, %; per JIS G 3141):

Key Alloy Advantage

The ultra-low carbon and impurity content enables SPCC to undergo simple cold forming processes (bending, stamping, blanking) without cracking, while maintaining sufficient strength for non-load-bearing components.

3. Mechanical Properties

SPCC cold rolled steel’s mechanical performance is tailored for general cold forming, with consistent data across industry sources (typical values for 0.5–2.0mm thick sheets, transverse testing):

Performance Note

Mechanical properties may vary slightly by thickness: thinner sheets (<0.5mm) exhibit marginally lower yield strength (+10–20MPa), while thicker sheets (>2.0mm) maintain stable performance with elongation reduced by 2–3%.

4. Product Forms, Surface Quality, and Dimensional Range

4.1 Core Product Forms

SPCC is supplied in flexible configurations to meet mass production needs:

• Steel Coils: Inner diameter (ID) 508mm/20", outer diameter (OD) ≤2100mm; ideal for continuous stamping lines.

• Steel Sheets: Standard sizes (1220×2440mm, 1500×3000mm); custom cut-to-length available.

• Steel Strips: Width 10–1250mm; suitable for precision components and small-part stamping.

• Slit Coils: Custom width slitting (10–1250mm) for specialized production lines.

4.2 Dimensional Range

• Thickness: Standard 0.1–3.2mm (common gauges: 0.3, 0.5, 0.8, 1.0, 1.2, 1.5mm); customized up to 6.0mm for heavy-duty applications.

• Width: Standard 1000mm, 1250mm, 1500mm; customized 10–2000mm.

• Length: Sheets 1000–6000mm; coils up to 300m (depending on thickness).

• Dimensional Tolerance: Thickness ±0.02mm (precision grade) to ±0.05mm (standard grade); width ±1mm (standard).

4.3 Surface Quality & Treatments

SPCC’s surface quality is classified to suit subsequent processing (painting, coating, or assembly):

Surface Treatment Options

• Oil Coating (SPCC+O): Temporary rust protection; compatible with cold forming (oil can be easily cleaned before painting).

• Phosphating (SPCC+C): Enhances paint adhesion and corrosion resistance; ideal for automotive and appliance components.

• Electrogalvanizing (SPCC+ZE): Thin zinc coating (5–20μm); improves corrosion resistance for outdoor use.

• Passivation: Forms a protective film to prevent oxidation during storage/transport.

5. Production Process & Quality Control

SPCC cold rolled steel undergoes a precision-controlled production process to ensure consistent quality and performance:

1. Raw Material Preparation: Hot-rolled coils (e.g., SS400) as feedstock; chemical composition verified to meet JIS G 3141.

2. Pickling: Removal of oxide scale via hydrochloric acid (18–22% concentration) at 60–80℃; ensures clean surface for cold rolling.

3. Cold Rolling: 3–5 passes of precision rolling to achieve target thickness and surface finish; thickness tolerance controlled to ±0.02mm.

4. Annealing: Continuous annealing at 650–750℃ to eliminate work hardening, refine grain structure, and restore ductility.

5. Skin Pass Rolling: 0.5–1.0% elongation to improve flatness, surface uniformity, and forming stability.

6. Surface Treatment: Oil coating or other treatments (phosphating/galvanizing) based on customer requirements.

7. Quality Inspection:

• Chemical Testing: Spectrometric analysis to verify element content.

• Mechanical Testing: Tensile, bend, and hardness tests for each production batch.

• Surface Inspection: 100% visual inspection + automated defect detection (e.g., scratch, pitting) via optical scanners.

• Dimensional Testing: Laser measurement for thickness, width, and flatness.

Certifications

All SPCC products comply with JIS G 3141 and ISO 9001 quality management system; additional certifications (CE, SGS, BV) are available for export markets.

6. Core Applications

SPCC’s balance of formability, cost, and surface quality makes it indispensable across industries:

6.1 Home Appliances

• Refrigerator door liners, washing machine control panels, air conditioner casings, microwave oven housings.

• Rationale: Smooth surface for painting, excellent stamping performance, and cost-effectiveness for mass production.

6.2 Automotive Industry

• Automotive interior parts (dashboard brackets, door trim, seat rails), small stamping components, and underbody shields.

• Rationale: Low cost, good bendability, and compatibility with phosphating/galvanizing treatments.

6.3 Electronics & Electrical

• Electronic device casings (smartphone/TV backplates), power distribution cabinets, and transformer shells.

• Rationale: Precision thickness control, smooth surface, and electromagnetic compatibility (low carbon content minimizes interference).

6.4 General Manufacturing & Packaging

• Stamped parts (brackets, clips, fasteners), metal containers, packaging materials, and furniture components.

• Rationale: Versatile formability, cost advantage, and suitability for high-volume production.

6.5 Construction & Decoration

• Lightweight decorative panels, door handles, and non-structural metal fittings.

• Rationale: Aesthetic surface finish, easy bending, and low weight.

7. Comparison with Similar Grades & Materials

7.1 SPCC vs. Other SPC Series Grades

The SPC series grades differ in formability (increasing from SPCC to SPCE):

7.2 SPCC vs. DC01 (EN 10130)

• Equivalent Performance: Nearly identical chemical/mechanical properties; interchangeable in most applications.

• Difference: SPCC follows JIS standards (Japanese market), DC01 follows European standards (global market).

7.3 SPCC vs. Stainless Steel (e.g., 304)

• Advantages of SPCC: 50–70% lower cost, better formability, and lighter weight.

• Disadvantages: Poor natural corrosion resistance (requires surface treatment for outdoor use); stainless steel offers superior rust resistance but higher cost.

8. Supply Chain & Value-Added Services

8.1 Order Terms

• Minimum Order Quantity (MOQ): 1 ton (standard sizes); 5 tons (customized dimensions/surface treatments).

• Delivery Lead Time: 7–10 days for stock products; 25–40 days for customized orders.

• Monthly Capacity: Major suppliers offer 3,000–5,000 MT monthly output.

8.2 Packaging & Logistics

• Packaging: Seaworthy export packaging (kraft paper + moisture-proof plastic film + steel strips) to prevent scratches and corrosion; wooden pallets for sheets/coils.

• Loading Ports: Shanghai, Tianjin, Qingdao (China); Yokohama, Osaka (Japan); Hamburg, Rotterdam (Europe).

• Global Reach: Exported to over 60 countries, including Japan, South Korea, Germany, France, USA, and Southeast Asia.

8.3 Value-Added Services

• Customized Cutting: Laser cutting, plasma cutting, and blanking to precise dimensions.

• Surface Treatment Customization: Tailored phosphating, galvanizing, or painting based on application needs.

• Technical Support: Engineering consultation for material selection and forming process optimization.

• Third-Party Testing: SGS/BV/TÜV testing reports for chemical composition, mechanical properties, and corrosion resistance.

9. Conclusion

SPCC cold rolled steel stands as the benchmark for cost-effective, general-purpose cold-rolled carbon steel, leveraging its excellent formability, smooth surface finish, and broad compatibility with processing treatments. As an equivalent to DC01 and ASTM A1008, it serves as a foundational material in mass-produced components across automotive, appliance, electronics, and manufacturing industries. While its natural corrosion resistance is limited, targeted surface treatments (galvanizing, phosphating) extend its utility to outdoor and harsh environments.

Backed by strict compliance with JIS G 3141, precision production processes, and a global supply chain, SPCC offers an unbeatable balance of performance, cost, and versatility. For buyers seeking a reliable material for simple-to-moderate forming applications, SPCC cold rolled steel remains the preferred choice—delivering consistent quality and value for high-volume production. When complex deep drawing is required, upgrading to SPCD or SPCE is recommended, while stainless steel or galvanized SPCC is ideal for corrosion-prone environments.