S235JR Steel

S235JR is a European standard non-alloy structural steel, which is a carbon structural steel with a low carbon content and is used in many welding, bolted and riveted structures. Carbon structural steel, English name: Carbon Structural Steel, a type of carbon steel. The carbon content is about 0.05% to 0.70%, and can be as high as 0.90% in some cases. It can be divided into two categories: ordinary carbon structural steel and high-quality carbon structural steel. It has many uses and a large amount of use. It is mainly used in railways, bridges, and various construction projects to manufacture various metal components that bear static loads, as well as unimportant mechanical parts and general welding parts that do not require heat treatment.

Material S235JR meaning (grade): "S" represents structure; "235" represents the minimum yield strength when the steel thickness is ≤16mm, in MPa (MPa); "JR" represents the room (20°C) Charpy impact test energy value ≥27J related quality grade; "C" indicates that the material is suitable for cold flanging, cold bending, cold forming or cold drawing, such as S235JRC (1.0122).1.0038 is the code name of steel grade

S235JR is the European standard, which is equivalent to the domestic Q235B. Q235 is an ordinary carbon structural steel with a yield value strength of around 235MPa, and its yield value will decrease as the thickness of the material increases. Due to its moderate carbon content and good overall performance, strength, plasticity and welding properties are well matched, and it has the most extensive uses.The letters after Q235 represent different impact temperatures. A means no impact, B is above 20 degrees, C is above 0 degrees, D is above 20 degrees, E is above 40 degrees. The difference between A and E refers to the difference in impact temperature in their performance. They are: Q235A grade, which does not require impact toughness test; Q235B grade, which is subject to normal temperature (20°C) impact toughness test; Q235C grade, which is subject to 0°C impact toughness test; Q235D grade, which is subjected to -20°C impact toughness test; Q235E is used for -40℃ impact toughness test. The impact toughness test uses Charpy V-shaped notch specimens. The impact toughness index is Akv. The above-mentioned B, C and D grade steels are required to achieve Akv≥27J under their respective different temperature requirements. At different impact temperatures, the impact values are also different.

S235JR delivery standard: S235JR steel plate implementation standard: implement EN10025 standard. , S235JR steel plate delivery status: hot rolling, controlled rolling, normalizing, etc. The delivery status can also be specified according to technical requirements. S235JR steel plate thickness direction performance requirements: Z15, Z25, Z35.

The chemical composition design of S235JR is based on the principle of meeting the performance requirements and reducing production costs. The composition design of S235JR complies with the EN10025 standard. S235JR structural steel has high requirements for strength and low temperature (0℃) impact toughness. Therefore, low-C and low-P ingredient control methods are adopted for ingredient control.

Physical properties of S235JR steel: Material density: 7.85g/cm3 (0.284 lb/in3). Melting point: 1420-1460 °C (2590-2660 °F). Conductivity: 0.141 × 10^6 S/m (at 20°C). Elasticity Modulus: 210 GPa (30500 ksi). Poisson's ratio: 0.3. Shear modulus: 80 GPa (11600 ksi). Specific heat capacity: 0.46 – 0.48 J/g-°C (50.0 – 100°C); 0.11 – 0.115 BTU/lb-°F (122 – 212°F)

Manganese is partially miscible with iron in steel to form a solid solution (ferrite or austenite), and partially mixed with iron, carbonized and formed cementite, which can strengthen ferrite and refine pearlite. At the same time, due to the strong affinity of Mn and S, it can promote the S in the steel to form MnS with a higher melting point than FeS, preventing FeS from precipitating at the grain boundaries, reducing hot brittleness, and improving hot workability . Appropriate addition of V, micro-alloy refines the grains, compensates for the strength lost due to C reduction of the steel type, and ensures that the low-temperature impact performance meets European standards. V in steel types forms carbides, nitrides or carbonitrides with C and N to produce fine grain strengthening and precipitation strengthening, which can significantly improve the strength and impact toughness of steel.

S235JR is not a corrosion-resistant steel, so protective coatings or other measures may be required to prevent corrosion in corrosive environments.

S235JR material is generally considered weldable using conventional welding methods. S235JR steel can be joined using common welding techniques such as arc welding, MIG welding and TIG welding. Depending on the thickness of the material and the welding process used, preheating and post-weld heat treatment may be required.

S235JR steel plate application scope: S235JR steel is commonly used in various structural and construction applications, including buildings, bridges, boilers, transmission towers, steel structures, shopping malls, machinery and vehicle chassis, etc.Suitable for making parts that require good weldability and medium strength. Due to its affordability and ease of processing, this material is commonly used for general engineering and structural purposes. EN 1.0038 materials can be made into a variety of steel materials, such as H-shaped steel, I-beam, channel steel, steel plate, angle steel, steel pipe, wire rod, nails, etc.