European Standard Designation Systems for Steel Names
1. Designation & Meaning of Structural Steel Names
- The first letter indicates the type of steel,
- The following digits indicates the yield strength MPa;
- The 2 symbols immediately after the yield strength value indicate the quality grade of the steel;
- The symbols immediately after the quality grade indicate characteristic/uses or treatment, and
- finally a plus sign (+) and a symbol indicate delivery/treatment conditions, coatings or special requirements.
For example,
S235JRC+C Meaning:
- “S” is the abbreviation for Structural steel.
- “235” refers to the yield strength in MPa.
- J indicates Joules (27 J)
- R is the abbreviation for Room temperature (20 °C).
- C means special cold forming (cold flanging, cold roll forming or cold drawing).
- “+C” indicates cold work hardened.
S235JRC+C Meaning: Structural steel (S) with a specified minimum yield strength 235 MPa at room temperature, minimum impact energy 27 J at room temperature 20 °C (JR), suitable for cold flanging (C), delivery condition +C (cold work hardened).
S355J2W Meaning: Structural steel (S) with a specified yield strength ≥355 MPa at room temperature, impact energy ≥27 J at -20 °C (J2), and is weather resistant (W).
S355MC Meaning: Structural steel (S), thermomechanically rolled (M), with a specified minimum yield strength at room temperature of 355 MPa (355) and suitable for cold forming (C).
| Basic constituent symbols indicating the quality grades of structural steel | |
|---|---|
| Symbol/Number | Meaning |
| S | Structural steel |
| 235 | Yield strength: 235 MPa |
| JR | Joules (27J) at Room temperature (+20°C) |
| J0 | Joules (27J) at 0°C |
| J2 | Joules (27J) at -20 °C |
| J3 | Joules (27J) at -30 °C |
| J4 | Joules (27J) at -40 °C |
| J5 | Joules (27J) at -50 °C |
| J6 | Joules (27J) at -60 °C |
| KR | Joules (40J) at Room temperature (+20°C) |
| K0 | Joules (40J) at 0°C |
| K2 | Joules (40J) at -20 °C |
| K3 | Joules (40J) at -30 °C |
| K4 | Joules (40J) at -40 °C |
| K5 | Joules (40J) at -50 °C |
| K6 | Joules (40J) at -60 °C |
| LR | Joules (60J) at Room temperature (+20°C) |
| L0 | Joules (60J) at 0°C |
| L2 | Joules (60J) at -20 °C |
| L3 | Joules (60J) at -30 °C |
| L4 | Joules (60J) at -40 °C |
| L5 | Joules (60J) at -50 °C |
| L6 | Joules (60J) at -60 °C |
| A | Precipitation hardening |
| M | Thermomechanically rolled |
| N | Normalized or normalized rolled |
| Q | Quenched and tempered |
| C | Special cold forming (cold flanging, cold roll forming or cold drawing) |
| D | Hot dip coating |
| E | Enamelling |
| F | Forgings |
| H | Hollow section |
| L | Low temperature |
| P | Sheet piling |
| P | For the class with a greater phosphorus content (only in the case of grade S355) |
| S | Ship building |
| T | Tubes |
| W | Weather resistant (improved atmospheric corrosion resistance) |
| Symbols that indicate the treatment of steel products | |
|---|---|
| Symbol | Meaning |
| +A | Soft annealed |
| +AC | annealed to achieve spheroidized carbides |
| +AR | as rolled (without any special rolling and/or heat treatment conditions) |
| +AT | solution annealed |
| +C | cold work hardened |
| +Cxxx | cold work hardened with a minimum tensile strength of xxx MPa |
| +CPxxx | cold work hardened with a minimum 0,2 % proof strength of xxx MPa |
| +CR | cold rolled |
| +DC | delivery condition at manufacturer’s discretion |
| +FP | treated to ferritic-pearlite structure and hardness range |
| +HC | hot rolled followed by cold hardening |
| +I | isothermically treated |
| +LC | skin passed (temper rolled or cold drawn) |
| +M | thermomechanically formed |
| +N | normalized or normalized formed |
| +NT | normalized and tempered |
| +P | precipitation hardened |
| +Q | quenched |
| +QA | air quenched |
| +QO | oil quenched |
| +QT | quenched and tempered |
| +QW | water quenched |
| +RA | recrystallization annealed |
| +S | treated for cold shearing |
| +SR | stress relieved |
| +T | tempered |
| +TH | treatment to hardness range |
| +U | untreated |
| +WW | warm worked |
| Symbols for steel products indicating the type of coating | |
|---|---|
| Symbol | Meaning |
| +A | hot dip aluminum coating |
| +AS | aluminum silicon alloy coating |
| +AZ | aluminum zinc alloy (>50 % Al) coating |
| +CE | electrolytic chromium/chromium oxide coating (ECCS) |
| +CU | copper coating |
| +IC | inorganic coating |
| +OC | organic coating |
| +S | hot dip tin coating |
| +SE | electrolytic tin coating |
| +T | hot dip lead tin alloy (terne) coating |
| +TE | electrolytic lead tin alloy (terne) coating |
| +Z | hot dip zinc (galvanized) coating |
| +ZA | hot dip zinc aluminum (>50 % Zn) coating |
| +ZE | electrolytic zinc coating |
| +ZF | hot dip zinc iron (galvannealed) coating |
| +ZM | hot dip zinc magnesium coating |
| +ZN | electrolytic zinc nickel alloy coating |
| Symbols for steel products indicating special requirements | |
|---|---|
| Symbol | Meaning |
| +CH | core hardenability |
| +H | hardenability |
| +Z15 | through thickness property; minimum reduction of area = 15 % |
| +Z25 | through thickness property; minimum reduction of area = 25 % |
| +Z35 | through thickness property; minimum reduction of area = 35 % |
