S890Q is an ultra-high-strength, structural steel plate that is quenched and tempered (Q) according to the European standard EN 10025-6. It is designed for heavy-duty applications where high load-bearing capacity and weight reduction are critical, such as in mining equipment, crane booms, and bridge structures.
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S890QChemical Composition |
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Grade |
The Element Max (%) |
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C |
Si |
Mn |
P |
S |
N |
B |
Cr |
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S890 Q |
0.20 |
0.80 |
1.70 |
0.020-0.025 |
0.010-0.015 |
0.015 |
0.005 |
1.50 |
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Cu |
Mo |
Nb |
Ni |
Ti |
V |
Zr |
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0.50 |
0.70 |
0.06 |
2.0 |
0.05 |
0.12 |
0.15 |
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Grade |
S890Q Mechanical Property |
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Thickness |
Yield |
Tensile |
Elongation |
Min Impact Energy
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S890 Q |
mm |
Min Mpa |
Mpa |
Min % |
-20 |
30J |
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3<t≦50 |
890 |
940-1100 |
11 |
-20 |
30J |
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50<t≦100 |
830 |
880-1100 |
11 |
-20 |
30J |
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100<t≦150 |
800 |
820-1000 |
11 |
-20 |
30J |
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Processing
1. Cutting & Edge Preparation
S890Q can be processed using both thermal and mechanical methods.
Thermal Cutting: Laser, plasma, and flame cutting are common.
Laser Cutting: Recommended for superior precision and better fatigue performance.
Preheating for Cutting: For plate thicknesses above 30 mm, it is advisable to preheat to 100–200°C before thermal cutting to ensure cold crack resistance.
Cold Cutting: Waterjet cutting, sawing, or shearing can be used to avoid creating a Heat Affected Zone (HAZ).
2. Welding Guidelines
S890Q is designed for good weldability, but its high strength necessitates strict control:
Preheat Temperature: Generally recommended to be between 100°C and 200°C, especially for thicknesses exceeding 30 mm or in environments below 5°C.
Filler Materials: Use low-hydrogen electrodes (e.g., E11018 or similar high-strength consumables) to prevent hydrogen-induced cracking.
Interpass Temperature: Must be monitored to avoid excessive heat input, which can soften the tempered microstructure and reduce strength.
3. Forming & Bending
Cold Forming: Standard for S890Q, typically performed at temperatures below the stress-relieving range (approx. 530–580°C).
Hot Forming: If performed between 700°C and 1050°C, the steel must be re-quenched and tempered afterward to restore its original mechanical properties.
Bending Radius: Due to its high strength, larger bending radii and higher press forces are required compared to standard mild steel.
4. Machining
S890Q is more challenging to machine than mild steel due to its hardness (typically 300–400 HBW).
Tooling: Use high-performance carbide tools with advanced coatings.
Strategy: Maintain moderate cutting speeds and adequate cooling to manage heat and prevent tool wear.
applications
1. Lifting and Handling Equipment
Crane Booms: Used extensively for mobile, loader, and tower crane booms to allow for higher reach and heavier lifting capacities.
Lifting Jibs: Its high yield strength (890 MPa) enables the design of lighter, more rigid telescopic jibs.
Forklift Parts: High-load structural components for heavy-duty forklifts and telehandlers.
2. Heavy Transport and Vehicles
By replacing lower-grade steels with thinner S890Q plates, manufacturers can increase vehicle payloads:
Truck Chassis: Used in the main frames of heavy transport trucks and trailers to reduce tare weight and improve fuel efficiency.
Dumper Bodies: Integrated into the load-bearing structures of electric wheel dump trucks and heavy-duty mining trailers.
3. Mining and Construction Machinery
S890Q provides the durability needed for the extreme mechanical stresses of the resource sector:
Earthmoving Equipment: Critical parts for excavators, loaders, bulldozers, and electric shovels.
Mining Infrastructure: Used in coal mine hydraulic supports and heavy-duty conveyor systems.
4. Structural Engineering and Infrastructure
In civil engineering, S890Q is used where extreme loads or long spans are required:
Bridges and Trestles: Ideal for highly loaded bridge members, allowing for longer spans and reduced material usage.
Skyscrapers: High-strength skeletons for high-rise buildings and towers where space-saving (thinner columns) is beneficial.
Offshore Structures: Utilized in offshore drilling rigs and supports for offshore wind turbines.
5. Energy and Pressure Vessels
Pressure Piping: Tested and approved for use in the construction of pressure vessels and pipes in high-pressure environments.
Transmission Towers: High-voltage towers and power distribution structural.
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.
What is S890Q steel used for?
S890Q is a high-strength quenched and tempered structural steel. It is widely used in heavy machinery, crane booms, offshore structures, and large steel constructions. Its high yield strength allows designers to reduce material thickness and overall weight while maintaining structural integrity and safety under heavy loads.
What are the key mechanical properties of S890Q?
S890Q typically has a minimum yield strength of 890 MPa and good toughness at low temperatures. It offers high tensile strength, excellent weldability, and good bending and forming characteristics. These properties make it suitable for demanding applications where high strength and reliability are required.
How does S890Q achieve its high strength?
S890Q achieves high strength through a quenching and tempering process. After hot rolling, the steel is rapidly cooled to form a hard martensitic structure, then reheated to a lower temperature to improve toughness and reduce brittleness. This heat treatment results in a fine-grained microstructure with high strength and good ductility.
What standards define S890Q steel?
S890Q is defined by European standards such as EN 10025-6, which covers high-strength structural steels. The standard specifies chemical composition, mechanical properties, and delivery conditions. Compliance with EN 10025-6 ensures consistent quality and performance across different manufacturers and applications.
What is the typical chemical composition of S890Q?
S890Q contains low carbon to ensure weldability, along with manganese, chromium, molybdenum, and nickel. These alloying elements improve hardenability, strength, and toughness. Small amounts of niobium, vanadium, and titanium may be added for grain refinement and further strength enhancement.
Is S890Q suitable for welding?
Yes, S890Q is generally suitable for welding, but proper procedures are essential. Preheating and interpass temperature control help prevent cold cracking. Low-hydrogen welding consumables are recommended. With correct welding parameters, S890Q can be joined reliably while maintaining its high strength and toughness.
What preheating is needed for welding S890Q?
Preheating temperatures for S890Q depend on thickness, restraint, and hydrogen level. Typical preheat ranges from 100 to 200 degrees Celsius. Thicker sections or high restraint may require higher preheat to reduce cooling rates and avoid hydrogen-induced cracking in the heat-affected zone.
What are the common welding methods for S890Q?
Common welding methods for S890Q include submerged arc welding, gas metal arc welding, and shielded metal arc welding. These methods can provide good fusion and mechanical properties when matched with appropriate consumables. Welding should follow qualified procedures to ensure joint strength and toughness.
How does S890Q perform in low-temperature environments?
S890Q exhibits good toughness at low temperatures, often tested at minus 40 degrees Celsius. Its fine-grained microstructure and tempered martensite provide resistance to brittle fracture. This makes it suitable for offshore and arctic applications where cold conditions are common.
What is the difference between S890Q and S690Q?
The main difference is yield strength: S890Q has 890 MPa, while S690Q has 690 MPa. S890Q offers higher strength but may require more careful welding and handling. S690Q is easier to process and weld. Material selection depends on load requirements and fabrication considerations.