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Q355NC STRUCTURAL STEEL

Chemical element composition – Chinese grade Q355NC low alloy high strength structural steel 🔍 Q355NC Grade Lookup →

Product Overview

Q355NC is a Chinese grade low-alloy high-strength structural steel conforming to GB/T 1591-2018 standard. It features a normalized or normalized plus tempered delivery condition, offering improved toughness and consistent properties. Grade C provides guaranteed impact toughness at 0°C. With minimum yield strength of 355MPa, it is widely used in building structures and heavy machinery requiring enhanced reliability in moderate low-temperature conditions.

Equivalent grades: Q355NC ↔ Q345C (previous domestic grade), EN 10025 S355J2 (Europe), ASTM A572 Grade 50 (USA).

International Grade Comparison

Europe (EN 10025-2)

S355J2

Impact: -20°C (27J)

Yield: 355MPa

C: ≤0.22%

Si: ≤0.55%

Mn: ≤1.60%

P: ≤0.025%

S: ≤0.025%

Nb: ≤0.05%

V: ≤0.12%

Ti: ≤0.05%

USA (ASTM A572)

Gr.50

Impact: Not specified

Yield: 345MPa

C: ≤0.23%

Si: ≤0.40%

Mn: ≤1.35%

P: ≤0.025%

S: ≤0.025%

Nb: ≤0.05%

V: ≤0.15%

Ti: ≤0.05%

China (GB/T 1591)

Q345C

Impact: 0°C (34J)

Yield: 345MPa

C: ≤0.20%

Si: ≤0.50%

Mn: 1.00-1.60%

P: ≤0.030%

S: ≤0.030%

Nb: ≤0.07%

V: ≤0.15%

Ti: ≤0.20%

Note: Q355NC is the normalized version of Q355C, offering improved toughness and consistent properties compared to hot-rolled grades; always verify specific requirements before substitution.

Grade Comparison: Q355NC vs Q355ND vs Q355NE vs Q355NF

Q355NC

Grade C

Impact: 0°C

KV2 (L): 34J

C: ≤0.20%

P: ≤0.030%

S: ≤0.030%

Q355ND

Grade D

Impact: -20°C

KV2 (L): 40J

C: ≤0.20%

P: ≤0.030%

S: ≤0.025%

Q355NE

Grade E

Impact: -40°C

KV2 (L): 31J

C: ≤0.18%

P: ≤0.025%

S: ≤0.020%

Q355NF

Grade F

Impact: -60°C

KV2 (L): 27J

C: ≤0.16%

P: ≤0.020%

S: ≤0.010%

Note: Q355N series grades share identical tensile properties (yield strength, tensile strength, elongation). The key differences are impact test temperature and corresponding impurity limits: C (0°C, 34J), D (-20°C, 40J), E (-40°C, 31J), F (-60°C, 27J), with progressively tighter P/S control for lower temperatures.

Key Advantages

Normalized Condition

Delivered in normalized or normalized plus tempered state for improved grain refinement and consistent mechanical properties.

Controlled Chemistry

Controlled carbon content and P/S levels ensure excellent weldability and toughness.

0°C Impact Toughness

Grade C provides guaranteed impact energy of 34J at 0°C (longitudinal), suitable for moderate low-temperature applications.

Applications

Building Structures

High-rise buildings, industrial plants, stadiums, steel frameworks requiring normalized steel.

Heavy Machinery

Construction machinery, crane booms, mining equipment, heavy vehicles requiring normalized steel.

Q355NC Chemical Composition (GB/T 1591-2018)

Grade Quality C Si Mn P S
Q355N C ≤0.20 ≤0.50 0.90-1.65 ≤0.030 ≤0.030
Nb V Ti Cr Ni Cu Mo N Als (min)
0.005-0.05 0.01-0.12 0.006-0.05 ≤0.3 ≤0.5 ≤0.4 ≤0.1 ≤0.015 ≥0.015

Notes:

a. For bars, P/S upper limit +0.005%.

b. V+Nb+Ti ≤0.22%, Mo+Cr ≤0.30%.

c. Ti up to 0.20% maximum.

d. Alt (total aluminum) can substitute Als with minimum 0.020%. When Nb/V/Ti added at specified levels, Als lower limit not required.

e. Steel must contain at least one grain-refining element (Al, Nb, V, Ti) with content not less than specified minimum.

Q355NC Tensile Properties (GB/T 1591-2018)

Upper yield strength ReH/MPa ≥
Grade ≤16mm 16-40mm 40-63mm 63-80mm 80-100mm 100-150mm 150-200mm 200-250mm
Q355NC 355 345 335 325 315 295 285 275
Property Thickness Range Value
Tensile Strength Rm ≤100mm 470-630 MPa
100-200mm 450-600 MPa
200-250mm 450-600 MPa
Elongation A % ≤16mm 22%
16-40mm 22%
40-63mm 22%
63-80mm 21%
80-200mm 21%
200-250mm 21%
Impact Temperature 20°C 0°C -20°C -40°C
KV2 (J) ≥ Longitudinal 63 34 47 31
Transverse 40 27 27 20

Notes: Normalized condition includes normalized and tempered condition. When yield not obvious, use Rp0.2.

Customizable Options

We offer comprehensive customization services to meet your specific project requirements:

Custom Dimensions
Non-standard sizes, laser cutting
Surface Treatments
Shot blasting, priming
Edge Preparation
Beveling, machining
Custom Heat Treatment
Normalizing, stress relieving
Special Testing
Third-party inspection
Custom Marking
Special labeling

Size & Specification

Product Form Thickness (mm) Width (mm) Length (mm)
Plate 6 - 80 1800 - 2500 3000 - 18000
Sheet / Coil 1.5 - 20 900 - 2000 Coil or cut to length

Other sizes can be produced upon request. Custom cutting available.

Quality & Manufacturing Assurance

Modern Production

Advanced continuous casting and normalized heat treatment for optimal grain refinement

In-process Inspection

Rigorous testing at each stage, including spectral analysis and impact testing at 0°C

Full Documentation

Mill Test Certificate (MTC) compliant with EN 10204 3.1/3.2

Packaging & Logistics

  • Packaging: Steel plates bundled with steel straps on wooden skids. Coils wrapped with waterproof paper and steel covers.
  • Marking: Each bundle/coil marked with grade, size, heat number, weight.
  • Logistics: FOB, CIF, CFR from main Chinese ports. Lead time 25-35 days after order.

Request a Quote

Emails go directly to customize@cehesteel.com — reply within 2h.

Frequently Asked Questions

What is Q355NC?

Q355NC is a normalized low-alloy structural steel per GB/T 1591-2018 with 355MPa min yield and 34J impact at 0°C.

What are the equivalents of Q355NC?

Q355NC is comparable to Q345C (previous domestic), EN 10025 S355J2 (Europe), and ASTM A572 Grade 50 (USA).

Weldability?

Excellent weldability due to controlled chemistry and fine-grain normalized structure.

Available thickness?

3mm to 250mm plates, 1.5-20mm coils/sheets with custom cutting available.

Mill certificates?

Yes, EN 10204 3.1 MTC with full data including 0°C impact test results.

MOQ?

Standard 5 tons. Sample orders possible.

What are the typical applications of Q355NC?

Q355NC is widely used in building structures and heavy machinery requiring normalized steel.