S960QL is a high-strength structural steel grade defined by the European standard EN 10025-6. It is a quenched and tempered material designed for load-bearing applications that require a combination of high yield strength and low-temperature toughness.
Naming Breakdown
S: Structural steel.
960: Minimum yield strength of 960 MPa (for thicknesses ≤ 50 mm).
Q: Quenched and tempered.
L: Low temperature impact testing, specifically at -40°C.
Key Specifications
| Feature | Detail |
|---|---|
| Material Number | 1.8933 |
| Standard | EN 10025-6 |
| Mechanical Properties | High yield strength (min 960 MPa) and high impact toughness (minimum 40 J at -40°C) |
| Approximate Equivalents | ASTM A514 and IS 2062 (Indian Standard). |
| Common Trade Names | Strenx 960 (SSAB), Amstrong Ultra 960QL (ArcelorMittal), and Dillimax 960 (Dillinger). |
Primary Applications
Due to its superior strength-to-weight ratio, it is used to reduce the weight of heavy structures while maintaining safety:
Lifting and Handling: Telescopic cranes, mobile cranes, and lifting equipment.
Transport: Trailer chassis, heavy-duty vehicle components, and bridge structures.
Mining and Earthmoving: Buckets for excavators, dump truck bodies, and mining supports.
Energy: Offshore structures and components for wind power.
Workshop Properties
Weldability: Good weldability, though sensitive to excessive heat input, which can soften the Heat Affected Zone (HAZ).
Formability: Excellent bendability and surface quality, allowing for complex cold-forming operations.
What standards apply to S960QL steel?
S960QL steel is governed by the European standard EN 10025-6, which defines the technical delivery conditions for quenched and tempered high-strength structural steels. Below is a detailed breakdown of applicable standards:
1. Core Material Standard
EN 10025-6: Hot rolled products of structural steels – Part 6: Technical delivery conditions for flat products of high yield strength structural steels in the quenched and tempered condition.
This standard specifies:
Minimum yield strength (960 MPa), tensile strength (980–1150 MPa), and elongation.
Impact toughness: Charpy V‑notch test at ‑40 °C (for the "QL" sub‑grade) with minimum energy values (e.g., ≥27 J for thicknesses ≤50 mm).
Chemical composition limits (C, Si, Mn, P, S, and micro‑alloys like Nb, V, Ti, B, plus alloying elements Ni, Cr, Mo).
2. Supporting Testing & Certification Standards
EN 10204: Defines inspection documents. S960QL typically requires a Type 3.1 Certificate, which involves independent verification by the manufacturer's quality department.
EN ISO 148‑1: Charpy pendulum impact test method.
EN ISO 6892‑1: Tensile test method.
EN ISO 6506‑1: Brinell hardness test method.
3. Design & Fabrication Standards (Application‑Specific)
EN 1993‑1‑10 (Eurocode 3): Provides guidelines for material selection based on toughness requirements (temperature, stress, thickness).
EN 1993‑1‑12: Extends Eurocode to steels up to S700. For S960QL, performance‑based design or special approvals are generally required.
EN ISO 15614‑1: Qualification of welding procedures (critical for S960QL due to strict welding constraints).
EN 1011‑2: Recommendations for welding steel structures.
4. Industry‑Specific Standards
Offshore/Marine: EN 10225 (welded steel offshore structures) or DNVGL/ABS rules may apply for certified components in cold environments.
Cranes & Lifting Equipment: FEM 1.001, ISO 8686, or EN 13001 often reference high‑strength steels for critical parts.
Military & Defense: Project‑specific specifications (e.g., German TL, U.S. MIL‑SPEC) may impose additional requirements.
5. International Equivalents
ISO 4950‑3: Covers similar high‑strength quenched and tempered steels, but EN 10025‑6 is the dominant reference.
ASTM A514/A517 (USA): No direct ASTM equivalent exists for S960QL. The closest grade in strength is A517 Grade 100 (~690 MPa yield), highlighting that S960QL exceeds typical ASTM high‑strength plate classifications.
Summary of Key Compliance Points:
To specify or procure S960QL, the minimum requirement is:
Material Standard: EN 10025‑6 (with sub‑grade S960QL).
Certification: EN 10204 Type 3.1 Inspection Certificate.
Application‑Specific Standards: Dependent on use (e.g., Eurocode for structures, EN ISO 15614‑1 for welding).
1. What is S960QL steel?
S960QL is an ultra-high-strength quenched and tempered structural steel with a minimum yield strength of 960 MPa, certified for good impact toughness at low temperatures down to -40°C.
2. Where is S960QL commonly used?
It is used in extreme weight-critical applications like advanced mobile crane booms, high-performance military vehicles, offshore lifting components, and specialized mining equipment operating in cold climates.
3. How does S960QL differ from S960Q?
S960QL is a sub-grade with guaranteed impact toughness at -40°C, while standard S960Q is typically tested at higher temperatures (often -20°C or 0°C).
4. What welding procedures are required for S960QL?
Welding S960QL requires strict preheating (150-250°C), low-hydrogen consumables, controlled heat input, and often post-weld heat treatment to prevent cracking and preserve toughness.
5. What is the chemical composition of S960QL?
It contains low carbon with micro-alloys (niobium, vanadium, titanium, boron) and elements like nickel, chromium, and molybdenum for hardenability and low-temperature toughness.
6. Can S960QL be machined easily?
No, machining S960QL is extremely difficult due to its high hardness; it requires premium carbide tools, high-pressure coolant, rigid setups, and optimized parameters.
7. What standards apply to S960QL steel?
It is governed by the European standard EN 10025-6 for quenched and tempered high-strength structural steels, with additional toughness requirements for the "QL" sub-grade.
8. Is S960QL corrosion resistant?
No, S960QL is not corrosion-resistant and requires protective coatings (e.g., painting, galvanizing) for use in corrosive or exposed environments.
9. What is the price range of S960QL steel plate?
S960QL is very expensive, typically ranging from €4,500 to €9,000+ per ton, depending on thickness, quantity, and certification.
Full specification and details are available on request. The above information is provided for guidance purposes only. For specific design requirements please contact our technical sales staff.
