S355JR is a low-alloy high-strength structural steel pipe conforming to European standard EN 10025-2, belonging to hot-rolled weldable fine-grained structural steel. Its naming convention is as follows:
"S" indicates structural steel, primarily used in structural engineering such as buildings and bridges.
"355" represents the minimum yield strength of the steel, which is 355 MPa, i.e., the minimum stress value at which the material begins to undergo plastic deformation under load.
"JR" indicates the impact toughness grade and delivery condition of the steel. "J" represents the energy level of the impact test, and "R" indicates that the impact test was conducted at room temperature (usually 20°C or 0°C, depending on the standard), and the steel is delivered in a hot-rolled condition.
ASTM A572 GR50 is a high-strength low-alloy (HSLA) steel, a type of steel microalloyed using elements such as niobium, vanadium, or titanium. The addition of these alloying elements improves the steel's strength and durability without significantly increasing its weight, making it suitable for applications where high strength is required and weight is a significant factor.
The high strength and low weight of ASTM A572 GR50 steel make it excellent in many applications. In the construction industry, it is often used to construct the structural frames of high-rise buildings; in the transportation sector, it is used to manufacture bridges, highways, and other important transportation infrastructure; and in the oil and gas industry, it is frequently used in the manufacture of pipelines and oil storage facilities.
SM490 is a Japanese standard low-alloy high-strength steel, conforming to the Japanese standard JIS G3106 specific technical conditions. "SM" indicates Japanese standard high-strength plate, while "490" indicates the strength of the steel plate. SM490 steel plate possesses high strength, high toughness, fatigue resistance, impact resistance, wear resistance, corrosion resistance, seismic welding properties, and easy machinability. It is commonly used in buildings, bridges, ships, rail vehicles, oil storage tanks, containers, and other construction requiring high weldability.
Q355B is a low-alloy high-strength structural steel. The "Q" in its name represents the yield strength, "355" indicates a yield strength of 355 MPa, and "B" indicates its quality grade. This steel is widely used in industrial production and construction, and due to its excellent mechanical properties and processing characteristics, it has become one of the preferred materials in many structural engineering projects.
Q355B V.S S355JR V.S SM490 V.S ASTM A572 Gr.50
| Property | Q355B (GB/T 1591) | S355JR (EN 10025-2) | SM490 (JIS G3106) | ASTM A572 Gr.50 |
|---|---|---|---|---|
| Chemical Composition (wt%) | ||||
| Carbon (C) | ≤ 0.20% | ≤ 0.24% | ≤ 0.20% | ≤ 0.23% |
| Manganese (Mn) | ≤ 1.60% | ≤ 1.60% | ≤ 1.60% | ≤ 1.35% |
| Phosphorus (P) | ≤ 0.035% | ≤ 0.045% | ≤ 0.035% | ≤ 0.040% |
| Sulfur (S) | ≤ 0.035% | ≤ 0.045% | ≤ 0.035% | ≤ 0.050% |
| Silicon (Si) | ≤ 0.55% | ≤ 0.55% | ≤ 0.55% | ≤ 0.40% |
| Copper (Cu) | - | - | - | ≥ 0.20% (when specified) |
| Mechanical Properties | ||||
| Min. Yield Strength | ≥ 355 MPa (50 ksi) | ≥ 355 MPa (50 ksi) | ≥ 325 MPa (47 ksi) | ≥ 345 MPa (50 ksi) |
| Min. Tensile Strength | 470-630 MPa (68-91 ksi) | 470-630 MPa (68-91 ksi) | 490-610 MPa (71-88 ksi) | ≥ 450 MPa (65 ksi) |
| Elongation (200mm gauge) | ≥ 22% | ≥ 22% | ≥ 21% (SM490A/B) | ≥ 21% |
S355JR Hollow Section Factory
