S420m steel is a fine-grain weldable structural steel that has been thermomechanically rolled. It conforms fully to the EN 10025-4/DSTU EN 10025-4 standard.
Classification: Structural steel.
Product: Steel plates and shaped steel.
Chemical composition of S420m steel according to DSTU EN 10025-4,%
| | Si | Mn | P | S | N | Cr | Cu | Mo | Nb | Ni | Ti | V | Al |
| | ≤0.50 | ≤1.70 | ≤0.030 | ≤0.025 | ≤0.025 | ≤0.30 | ≤0.55 | ≤0.20 | ≤0.05 | ≤0.80 | ≤0.05 | ≤0.12 | ≥0.02 |
Mechanical properties of S420m steel
| Nominal gauge, mm | Minimum yield strength, ReH (MPa) | Ultimate tensile strength, Rm (MPa) | Minimum elongation ratio σ, % |
| ≤16 | 420 | 520-680 | 19 |
| > 16 ≤ 40 | 400 | 520-680 | 19 |
| > 40 ≤ 63 | 390 | 500-660 | 19 |
| > 63 ≤ 80 | 380 | 480-640 | 19 |
| > 80 ≤ 100 | 370 | 470-630 | 19 |
| > 100 ≤ 120 | 365 | 460-620 | 19 |
Analogues to S420M steel
| Germany (DIN) | StE420TM |
| US | ASTM A572 Gr.60 |
| Italy (UNI) | FeE420KGTM |
Application
Products made from S420m steel are used in welded structures, large boats and ships, various machinery, bridge supports and metal structures, as well as supporting structures for wind turbines. The steel is used in highway construction and other engineering projects.
Welding
Given its low carbon content and equivalent carbon content, S420m steel is ideally suited to both manual and automatic welding using all the main processes. Its low susceptibility to cold cracking makes preheating unnecessary. Nonetheless, the quality of the weld seam depends on the welding process, conditions and use of appropriate welding filler. Oxyfuel gas welding is not recommended. Filler wire and welding rods must be used as welding filler for this strength category. Basic-covered electrodes are recommended for manual welding. These brands are not suitable for heat-treatment above 580°C. The processor of these brands must ensure that the calculations, design and processing methodology are suitable for the material.
