S275JR and S355JR steel are low alloy steel materials under standard EN10025-2. In the steel grades, “S” means structure steel, the number “275” and “355” means the Min. yield strength of S275JR and S355JR steel are 275Mpa and 355Mpa respectively. “JR” indicates the steel needs +20℃ impact test.
What is the difference between S275JR and S355JR steel?
Chemical composition difference between S275JR and S355JR steel: %
Grade | C (t≤16mm) | Si | Mn | P | S | Cu | N |
S275JR | 0.24 max | - | 1.60 max | 0.045 max | 0.045 max | 0.60 max | 0.014 max |
S355JR | 0.27 max | 0.6 | 1.70 max | 0.045 max | 0.045 max | 0.60 max | 0.014 max |
Mechanical properties difference between S275JR and S355JR steel:
Grade | Yield strength ReH/(N/mm2) (t≤16mm) min | Tensile strength Rm/(N/mm2) (3mm≤t≤16mm) | Elongation A/%(3mm≤t≤40mm) min | Charpy V test | |
Temperature/℃ | Impact energy (Longitudinal)/J min | ||||
S275JR | 275 | 410-560 | 23 | 20 | 27 |
S355JR | 355 | 470-630 | 22 | 20 | 27 |
The chemical composition difference between S275JR and S355JR steel is not outstanding other than Carbon content. The carbon content of S355JR steel is higher than S275JR steel. Accordingly, the S355JR steel strength is higher than S275JR steel strength.