Steel S550MC-TM
Print state · default condition
EN S550MC · GB Q550M
TM = thermomechanically rolled, as-delivered hot-rolled coil/sheet
Standard EN 10149-2 delivery condition for cold-formed structural parts, 1.5–16 mm.
Values for the TM condition
Other S550MC tempers and conditions
S550MC is listed in 3 conditions; see the grade overview at S550MC.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
TMDefaultThis page Thermomechanically rolled, as-delivered hot-rolled coil/sheet | Standard EN 10149-2 delivery condition for cold-formed structural parts, 1.5–16 mm. | 595 | 680 | 16 | 200 HB | — |
TM + pickled and oiled | Choose for direct press forming, laser cutting and painting where mill scale is unacceptable. | 600 | 680 | 15 | 14 HRC | 9 % IACS |
TM + skin-passed / temper rolled | Light temper pass for improved flatness and suppression of yield-point elongation on visible pressings. | 615 | 690 | 14 | 15 HRC | 9 % IACS |
What is S550MC-TM?
S550MC-TM is S550MC in the TM condition — standard EN 10149-2 delivery condition for cold-formed structural parts, 1.5–16 mm. S550MC-TM has a yield strength of 595 MPa (86.3 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 76% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi). S550MC-TM has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F).
Advantages
- Readily welded — 80/100, better than 79% of steel grades
- Forms and bends easily — 62/100, better than 78% of steel grades
- High strength — 595 MPa (86.3 ksi), better than 76% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
S550MC-TM properties
Typical room-temperature values for S550MC-TM; 10 are specific to this condition. Other listed values are S550MC reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
S550MC-TM has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,500°C (2,732 °F).
Mechanical16
S550MC-TM has a yield strength of 595 MPa (86.3 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 76% of steel grades. Elongation at break is 16% and the elastic modulus is 210 GPa (30.5 Msi).
Thermal6
S550MC-TM is rated for continuous service to 350°C (662 °F). It conducts heat at 45 W/m·K (26 BTU/hr·ft·°F), better than 66% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
S550MC-TM conducts electricity at 9 % IACS, better than 71% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (12/100), worse than 53% of steel grades.
Sustainability4
Producing a kilogram of S550MC-TM takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 25%.
Manufacturability7
S550MC-TM's machinability is fair (45/100, worse than 65% of steel grades); weldability very good (80/100); formability good (62/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with S550MC-TM
Is S550MC easy to machine?
Machinable with carbide at moderate speeds; the fine-grained microstructure gives stringy chips — use positive rake and chip-breaking geometry, plan for ~55 % of 1212 speeds.
Can S550MC be welded?
Excellent weldability with low CEV; use low-hydrogen consumables of matching or slightly undermatching strength, limit heat input (~1.0–1.5 kJ/mm) and avoid post-weld normalising, which destroys the TM strength.
Can S550MC be formed, bent or molded?
Designed for cold forming — typical minimum inner bend radius 1.5–2.0×t transverse to rolling direction; allow for ~15–20° springback and roll-form rather than hard-bend thick sections.
What surface finishes work on S550MC?
Bare steel must be protected: shot-blast or pickle, then e-coat, powder coat, primer/paint or zinc plating; hot-dip galvanizing is possible but keep bath time short to avoid softening.
S550MC chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Cladle analysis, EN 10149-2 | ≤ 0.12 | 0.08 |
| Si | ≤ 0.5 | 0.2 |
| Mn | ≤ 1.8 | 1.55 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.02 | 0 |
| Altotal Al, min value | ≥ 0.02 | 0.04 |
| NbNb+V+Ti ≤ 0.22 total | ≤ 0.09 | 0.05 |
| V | ≤ 0.2 | 0.03 |
| Ti | ≤ 0.15 | 0.05 |
| Mooptional, producer dependent | ≤ 0.5 | 0.02 |
| Boptional | ≤ 0.01 | 5×10⁻⁴ |
| Fe | balance | — |
S550MC-TM — frequently asked
What is S550MC-TM used for?
S550MC-TM is typically used for crane telescopic boom sections, high-strength vehicle chassis parts, trailer and semi-trailer frame members, roll-formed high-strength profiles, lifting and handling equipment arms and tipper and skip body reinforcements. In short: highest-yield cold-forming HSLA; weldable 595 MPa structural sheet; stronger than S500MC.
What is the yield strength of S550MC-TM?
S550MC-TM has a typical yield strength of 595 MPa (86.3 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 76% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is S550MC-TM easy to machine?
Reasonably — machinability is rated fair (45/100, worse than 65% of steel grades). Machinable with carbide at moderate speeds; the fine-grained microstructure gives stringy chips — use positive rake and chip-breaking geometry, plan for ~55 % of 1212 speeds.
Can S550MC-TM be welded?
Yes — weldability is rated very good (80/100). Excellent weldability with low CEV; use low-hydrogen consumables of matching or slightly undermatching strength, limit heat input (~1.0–1.5 kJ/mm) and avoid post-weld normalising, which destroys the TM strength.
What surface finishes work on S550MC-TM?
Bare steel must be protected: shot-blast or pickle, then e-coat, powder coat, primer/paint or zinc plating; hot-dip galvanizing is possible but keep bath time short to avoid softening.
Can S550MC-TM be formed, bent or molded?
Designed for cold forming — typical minimum inner bend radius 1.5–2.0×t transverse to rolling direction; allow for ~15–20° springback and roll-form rather than hard-bend thick sections.
What is the maximum service temperature of S550MC-TM?
S550MC-TM is rated for continuous use to about 350°C (662 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- EN 10149-2 Hot-rolled flat products made of high yield strength steels for cold forming — Part 2: Thermomechanically rolled steels — CEN (2013)
- High-strength hot-rolled structural steel S550MC data sheets — SSAB / ArcelorMittal / voestalpine (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.