Q355ME Structural Steel

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Q355ME STRUCTURAL STEEL (TMCP)

TMCP Delivery | Grade Q355ME | Yield 355MPa | Impact -40°C 31J | Extreme Low-Temperature Toughness 🔍 Q355ME Grade Lookup →

Product Overview

Q355ME is a Chinese grade low-alloy high-strength structural steel conforming to GB/T 1591-2018 standard. Delivered in thermomechanically rolled (TMCP) condition, it offers refined grain structure, excellent weldability, and guaranteed extreme low-temperature toughness. The quality grade E provides impact properties at -40°C (longitudinal min. 31J). With minimum yield strength of 355MPa (≤16mm), it is ideal for arctic engineering, offshore structures, and critical building applications requiring exceptional performance in severe cold environments.

Equivalent grades: Q355ME ↔ Q345E (previous domestic grade), EN 10025-4 S355ME / S355ML (Europe), ASTM A572 Grade 50 (TMCP processed).

International Grade Comparison (TMCP / Thermomechanical Rolling)

Europe (EN 10025-4)

S355ME

Impact: -40°C (40J)

Yield: 355MPa

C: ≤0.14%

Si: ≤0.50%

Mn: ≤1.60%

P: ≤0.025%

S: ≤0.020%

Nb+V+Ti: ≤0.22%

Europe (EN 10025-4)

S355ML

Impact: -50°C (27J)

Yield: 355MPa

C: ≤0.14%

Si: ≤0.50%

Mn: ≤1.60%

P: ≤0.025%

S: ≤0.020%

Nb+V+Ti: ≤0.22%

China (GB/T 1591)

Q355ME

Impact: -40°C (31J)

Yield: 355MPa

C: ≤0.14%

Si: ≤0.50%

Mn: ≤1.60%

P: ≤0.025%

S: ≤0.020%

Nb: 0.01-0.05%

V: 0.01-0.10%

Ti: 0.006-0.05%

Delivery: TMCP, grade E -40°C impact

USA (ASTM A572)

Gr.50

Impact: Optional (TMCP version)

Yield: 345MPa min

C: ≤0.23%

Si: ≤0.40%

Mn: ≤1.35%

P: ≤0.025%

S: ≤0.025%

Nb+V: ≤0.15%

Note: Q355ME is delivered in TMCP (thermomechanically rolled) condition, offering refined grain structure and guaranteed impact toughness at -40°C. S355ME and S355ML are European TMCP equivalents with similar or lower temperature impact; ASTM A572 Gr.50 can be supplied with TMCP processing upon request.

China Grade Comparison: Q345E vs Q355ME (TMCP)

Q345E (Previous)

As-rolled / Normalized

Yield: 345MPa (≤16mm)

Impact -40°C: 31J

C: ≤0.18%

Delivery: As-rolled or normalized

Q355ME (TMCP)

TMCP (Thermomechanical Rolling)

Yield: 355MPa (≤16mm)

Impact -40°C: 31J

C: ≤0.14% (lower carbon)

Delivery: TMCP, refined grain, superior weldability, guaranteed -40°C toughness

Key Advantages (TMCP Technology)

Higher Strength

Min yield 355MPa (≤16mm), tensile 470-630MPa.

Extreme Low-Temp Toughness

Guaranteed KV2 31J at -40°C (longitudinal).

Excellent Weldability

Low carbon equivalent (CEV) due to ≤0.14% C content.

Applications

Building Structures

High-rise buildings, stadiums, industrial plants, arctic and cold-region construction requiring -40°C impact reliability.

Engineering Structures

Bridge girders, transmission towers, offshore platforms, polar infrastructure, heavy machinery in extreme cold environments.

Q355ME Chemical Composition (GB/T 1591-2018, TMCP)

Chemical element composition of Chinese grade Q355ME low alloy high strength structural steel

Current manufacturing execution standard: GB/T 1591-2018
Q355ME Approximate Grade Lookup Table

Grade Quality C ≤ Si ≤ Mn ≤ P ≤ S ≤
Q355M E 0.14ᵈ 0.50 1.60 0.025 0.020
Nb V Ti Cr ≤ Ni ≤ Cu ≤ Mo ≤ N ≤ B Als ≥
0.01-0.05 0.01-0.10 0.006-0.05 0.3 0.5 0.4 0.1 0.015 — 0.015

Notes: a. For structural steel and bars, P/S can increase by 0.005%. b. Ti can be as high as 0.2%. c. All-aluminum (Alt) min 0.02% if substituted; grain-refining elements rule applies. d. For structural steel and bars, max carbon content can be increased by 0.02%.

The steel shall contain at least one grain-refining element (Al, Nb, V, Ti) with content not less than lower limit.

Q355ME Mechanical Properties (TMCP, GB/T 1591-2018)

Upper yield strength ReH (MPa, min)

≤16mm 16-40mm 40-63mm 63-80mm 80-100mm 100-120mm
355 345 335 325 325 320

Tensile strength Rm (MPa)

≤40mm 40-63mm 63-80mm 80-100mm 100-120mm
470-630 450-610 440-600 440-600 430-590

Elongation A% (min): 22% (across all thickness ranges)

Impact KV2 (J) min – Quality E (extreme low-temperature)

Temperature Longitudinal Transverse
20°C 63 40
0°C 55 34
-20°C 47 27
-40°C 31 20
Note: Thermomechanically rolled (TMCP) condition includes TMCP + tempered condition. If yield not obvious, use Rp0.2. For thickness >120mm, consult technical specifications.

Size & Specification

Product Thickness (mm) Width (mm) Length (mm)
Plate 3-120 1000-4000 3000-18000
Sheet/Coil 1.5-20 900-2000 Coil or cut length

Custom sizes and cutting available upon request.

Customizable Options

Laser/plasma cutting, edge beveling, shot blasting, priming, third-party inspection, custom marking.

Quality Assurance

Full Testing
Spectral analysis, tensile & impact, ultrasonic
MTC 3.1/3.2
Full traceability & EN10204 docs

Packaging & Logistics

Bundled with steel straps, waterproof wrapping, clear marking. FOB, CIF, CFR from major Chinese ports. Lead time: 25-35 days.

Request a Quote

Direct email: customize@cehesteel.com – reply within 2 hours.

Frequently Asked Questions

What is Q355ME?

Thermomechanically rolled (TMCP) low-alloy high-strength steel per GB/T 1591-2018, min yield 355MPa, grade E guarantees impact 31J at -40°C.

Equivalent to S355ME?

Yes, Q355ME is comparable to EN 10025-4 S355ME and S355ML, also ASTM A572 Grade 50 with TMCP processing. Replaces previous Q345E grade.

Difference Q355ME vs Q345E?

Q355ME features lower carbon content (≤0.14% vs ≤0.18%), TMCP delivery ensures refined grain structure, better weldability, and higher yield strength (355MPa vs 345MPa).

Typical applications?

Engineering structures (bridges, towers, offshore platforms, polar infrastructure) and building structures (high-rise buildings, arctic industrial facilities) requiring -40°C impact toughness.