Q390D quality grade specifications 3mm 4mm 5mm 6mm 8mm 10mm 12mm

The differences are mainly reflected in quality grade, production process, performance characteristics, and application scenarios, with specific comparisons as follows:

1. Q390C Steel Plate

• Quality Grade: Grade C (requiring impact toughness at room temperature)
• Production Process: Can be produced by hot rolling, normalizing, or thermomechanical controlled processing (TMCP)
• Core Characteristics:
  • Mechanical Properties: Yield strength ≥390MPa, tensile strength 490–650MPa, impact energy at room temperature ≥34J
  • Composition Features: Contains microalloying elements (niobium, vanadium, titanium), carbon equivalent ≤0.45%, good weldability
• Typical Applications:
  • Building steel structures, engineering machinery (crane booms, excavator chassis)
  • Heavy-duty structural components for conventional temperature environments (above 0°C)

2. Q390NC Steel Plate

• Quality Grade: Grade D (requiring low-temperature impact toughness)
• Production Process: Must be normalized or normalized rolled (designation "N")
• Core Characteristics:
  • Low-Temperature Toughness: Impact energy at -20°C ≥34J, suitable for frigid regions
  • Composition Optimization: Addition of niobium (Nb: 0.01–0.05%) and vanadium (V) to refine grains and improve strength-toughness balance
• Typical Applications:
  • Bridges in cold regions, wind power tower sections, low-temperature pressure vessels
  • Heavy equipment requiring high low-temperature crack resistance
    

  • High-strength coil	11.5	Q390C		1500	1	28.4
    High-strength coil	11.5	Q390C		1500	1	28.59
    High-strength coil	7.5	Q390C		1500	1	28.69
    High-strength coil	7.5	Q390C		1500	1	28.76
    High-strength coil	5.5mm	Q390C		1600	1	29.02
    High-strength coil	5.75mm	Q390C		1500	1	28.62
    High-strength coil	11.5	Q390C		1500	1	28.95
    High-strength coil	4.5mm	Q390C		1500	1	28.65