S550QL is a quenched and tempered low-alloy high-strength structural steel that complies with the European standard EN 10025 - 6, with its material number being 1.8926. It is widely recognized for its excellent high strength, outstanding low-temperature toughness, and good weldability, and is widely used in many key industrial fields.
| Grade : | S550QL | ||
| Number: | 1.8926 | ||
| Classification: | Alloy special steel with specified minimum values of impact energy at temperatures not lower than -40 °C | ||
| Standard: |
|
||
| Equivalent grades: | Go here |
Chemical composition % of steel S550QL (1.8926): EN 10025-6-2004
| Nominal thickness =< 50(mm) CEV max = 0.65 Nominal thickness from 50 to 100 (mm) CEV max = 0.77 Depending on the thickness of the product and the manufacturing conditions, the manufacturer may add to the steel one or several alloying elements up to the maximum values given in order to obtain the specified properties Nb, Ti, V, Zr: There shall be at least 0.015% of a grain-refining element present. AL is also one of these elements. The minimum content of 0.015% applies to soluble aluminium, this value is regarded as attained if the total aluminium content is at least 0.018%; in case of dispute the soluble aluminium content shall be determined |
| C | Si | Mn | Ni | P | S | Cr | Mo | V | N | Nb | Ti | Cu | Zr | B | CEV |
| max 0.2 | max 0.8 | max 1.7 | max 2 | max 0.02 | max 0.01 | max 1.5 | max 0.7 | max 0.12 | max 0.015 | max 0.06 | max 0.05 | max 0.5 | max 0.15 | max 0.005 | max 0.83 |
Mechanical properties of steel S550QL (1.8926)
| Nominal thickness (mm): | 3 - 100 | 100 - 150 |
| Rm - Tensile strength (MPa) | 640-820 | 590-770 |
| Nominal thickness (mm): | 3 - 50 | 50 - 100 | 100 - 150 |
| ReH - Minimum yield strength (MPa) | 550 | 530 | 490 |
| KV - Impact energy (J) longitud., | 0° 50 |
-20° 40 |
-40° 30 |
| A - Min. elongation Lo = 5,65 √ So (%) | 16 |
Equivalent grades of steel S550QL (1.8926)
Warning! Only for reference
| EU EN |
Germany DIN,WNr |
France AFNOR |
European old EN |
Inter ISO |
||||||
| S550QL |
|
|
|
|
What do the codes in the S550QL grade mean, and which standard does it comply with?
S550QL is a quenched and tempered high-strength structural steel conforming to the European standard EN 10025 - 6, with a material number of 1.8926. "S" stands for structural steel, "550" represents its minimum yield strength of 550MPa for thin plates, "Q" indicates the quenched and tempered delivery condition, and "L" means it has enhanced low-temperature toughness, meeting impact performance requirements at -40°C. This coding rule enables engineers to quickly identify its core performance characteristics.
What are the key chemical composition characteristics of S550QL?
The chemical composition of S550QL is strictly regulated, with the maximum carbon content limited to 0.20% to ensure weldability, and harmful impurities strictly controlled (phosphorus ≤0.020%, sulfur ≤0.010%). It also contains alloy elements such as manganese (≤1.70%), chromium (≤1.50%), and molybdenum (≤0.70%), along with trace elements like niobium and titanium. These elements work together to enhance the steel's strength and toughness while improving its overall mechanical stability.
How do the mechanical properties of S550QL vary with plate thickness?
Its mechanical properties show a slight downward trend in strength as thickness increases. For plates 3 - 50mm thick, the yield strength is 550MPa and tensile strength is 640 - 820MPa; for 50 - 100mm plates, the yield strength drops to 530MPa but the tensile strength remains the same; for 100 - 150mm plates, the yield strength is 490MPa and tensile strength is 590 - 770MPa. Notably, its elongation is always no less than 16%, and the minimum impact energy at -40°C is 30J.