ST52 seamless steel pipe chemical composition and mechanical properties

Hit：92026-02-02 15:27:56　

ST52 seamless steel pipe chemical composition and mechanical properties
1. Mechanical performance
The mechanical properties of St52-3 comply with the DIN 17100 standard, which corresponds to the Chinese national standard Q355B and the European standard S355JR. The main performance indicators are as follows:
Yield strength (ReH, MPa) ≥ 355 (when thickness ≤ 16mm)
Gradually decreasing with increasing thickness, for example, 16-40mm is ≥ 345MPa
Tensile strength (Rm, MPa) 490-630 MPa
Post fracture elongation (A) ≥ 18% -22% (depending on thickness and standard)
Impact energy (KV2, 0 ℃) ≥ 23J (some quality grades require higher)
2. Chemical composition (mass fraction%)
As the most commonly used grade in the St52 series, St52-3 emphasizes a combination of low-carbon and high manganese in its chemical composition design to achieve a balance between strength, toughness, and weldability
Carbon (C): ≤ 0.20% - Ensure good welding performance and avoid quenching and cracking
Silicon (Si): ≤ 0.50% - used for deoxidation and solid solution strengthening
Manganese (Mn): 0.90% -1.65% - improves hardenability, strength, and toughness
Phosphorus (P): ≤ 0.040% (some standards require ≤ 0.035%) - strictly controlled to reduce the tendency of cold brittleness
Sulfur (S): ≤ 0.040% (some standards require ≤ 0.035%) - reduces the risk of thermal cracking
Other trace elements: may contain chromium (Cr), nickel (Ni), copper (Cu), niobium (Nb), vanadium (V), titanium (Ti), etc., please refer to the steel mill quality assurance certificate for details
St52 steel is a common German standard non alloy structural steel widely used in mechanical manufacturing, engineering structures, and other fields, with good weldability and mechanical performance balance.