Steel Q235D TMCP
Supply condition
GB Q235D
TMCP = thermomechanically controlled processed
Use for thick plate where high toughness at −20 °C with a low carbon equivalent (low preheat welding) is wanted.
Values for the TMCP condition
Other Q235D tempers and conditions
Q235D is listed in 6 conditions; see the grade overview at Q235D.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition, for maximum cold formability or to relieve stresses after heavy forming or welding. | 240 | 400 | 33 | 115 HB | 11 % IACS |
HRDefault Hot rolled | Default mill condition for plate, sections, coil and bar; use for general welded structures needing −20 °C toughness. | 265 | 430 | 29 | 130 HB | — |
Normalized | Pick for heavy plate/forgings where uniform fine grain and reliable sub-zero impact energy through thickness are required. | 275 | 440 | 31 | 128 HB | 10.8 % IACS |
TMCPThis page Thermomechanically controlled processed | Use for thick plate where high toughness at −20 °C with a low carbon equivalent (low preheat welding) is wanted. | 290 | 450 | 30 | 135 HB | 10.8 % IACS |
Cold rolled | Thin-gauge sheet for pressed parts and enclosures where surface finish and dimensional accuracy matter. | 310 | 420 | 22 | 140 HB | 10.8 % IACS |
Cold drawn | Choose for shafts, pins and machined parts needing tight tolerance, bright finish and higher yield strength. | 400 | 500 | 14 | 170 HB | — |
What is Q235D TMCP?
Q235D TMCP is Q235D supplied in the TMCP condition — use for thick plate where high toughness at −20 °C with a low carbon equivalent (low preheat welding) is wanted. Q235D TMCP has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 88% of steel grades. Elongation at break is 30% and the elastic modulus is 206 GPa (29.9 Msi). Q235D TMCP has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F). HR is the default condition FabDigit quotes; TMCP is available on request or by drawing note.
Advantages
- Readily welded — 96/100, better than 100% of steel grades
- Easy to machine — 68/100, better than 95% of steel grades
- Tough — resists crack growth — 140 MPa·√m (127.4 ksi·√in), better than 94% of steel grades
- High electrical conductivity — 10.8 % IACS, better than 94% of steel grades
- Forms and bends easily — 84/100, better than 94% of steel grades
Limitations
- Low strength — 290 MPa (42.1 ksi), worse than 88% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
Q235D TMCP properties
Typical room-temperature values for Q235D TMCP; 22 are specific to this condition. Other listed values are Q235D reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
Q235D TMCP has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,495°C (2,723 °F).
Mechanical16
Q235D TMCP has a yield strength of 290 MPa (42.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 88% of steel grades. Elongation at break is 30% and the elastic modulus is 206 GPa (29.9 Msi).
Thermal6
Q235D TMCP is rated for continuous service to 350°C (662 °F). It conducts heat at 50 W/m·K (28.9 BTU/hr·ft·°F), better than 87% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
Q235D TMCP conducts electricity at 10.8 % IACS, better than 94% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of Q235D TMCP takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 22%.
Manufacturability6
Q235D TMCP's machinability is good (68/100, better than 95% of steel grades); weldability excellent (96/100); formability very good (84/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Q235D TMCP
Is Q235D easy to machine?
Machines easily with HSS or carbide at ~68 % of AISI 1212; low carbon makes it gummy, so use sharp positive-rake tools, high speed and good chip evacuation for clean threads and finishes.
Can Q235D be welded?
Excellent weldability by SMAW/GMAW/SAW with E43xx (E6013/E7018 class) consumables; CEV ≈ 0.30–0.35 so no preheat below ~30 mm, use low-hydrogen electrodes to preserve the −20 °C impact requirement.
Can Q235D be formed, bent or molded?
Good cold bending and pressing per the GB/T 700 cold-bend test (d = a for ≤60 mm); hot forming at 1150–850 °C, avoid finishing below 800 °C to keep grain fine.
What surface finishes work on Q235D?
No natural corrosion resistance — specify shot blasting to Sa 2½ plus paint, hot-dip galvanizing or zinc-rich primer; can be phosphated, black oxided or electroplated.
Q235D 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 |
|---|---|---|
| CGB/T 700-2006 Q235D | ≤ 0.17 | 0.15 |
| Si | ≤ 0.35 | 0.22 |
| Mn | ≤ 1.4 | 0.55 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.04 | 0.02 |
| Alacid-soluble Al when fine-grain/killed practice is applied | ≥ 0.02 | 0.03 |
| Fe | balance | — |
Q235D TMCP — frequently asked
What is Q235D TMCP used for?
Q235D TMCP is typically used for structural steel, low-temperature service structures and welded assemblies. In short: cold-climate Q235 grade; −20 °C impact tested; highly weldable structural steel.
What is the yield strength of Q235D TMCP?
Q235D TMCP has a typical yield strength of 290 MPa (42.1 ksi) and a tensile strength of 450 MPa (65.3 ksi) — weaker than 88% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is Q235D TMCP easy to machine?
Reasonably — machinability is rated good (68/100, better than 95% of steel grades). Machines easily with HSS or carbide at ~68 % of AISI 1212; low carbon makes it gummy, so use sharp positive-rake tools, high speed and good chip evacuation for clean threads and finishes.
Can Q235D TMCP be welded?
Yes — weldability is rated excellent (96/100). Excellent weldability by SMAW/GMAW/SAW with E43xx (E6013/E7018 class) consumables; CEV ≈ 0.30–0.35 so no preheat below ~30 mm, use low-hydrogen electrodes to preserve the −20 °C impact requirement.
What surface finishes work on Q235D TMCP?
No natural corrosion resistance — specify shot blasting to Sa 2½ plus paint, hot-dip galvanizing or zinc-rich primer; can be phosphated, black oxided or electroplated.
Can Q235D TMCP be formed, bent or molded?
Good cold bending and pressing per the GB/T 700 cold-bend test (d = a for ≤60 mm); hot forming at 1150–850 °C, avoid finishing below 800 °C to keep grain fine.
What is the maximum service temperature of Q235D TMCP?
Q235D TMCP 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.
What is the difference between Q235D-HR and Q235D-CD?
HR is the default condition — default mill condition for plate, sections, coil and bar; use for general welded structures needing −20 °C toughness. CD: choose for shafts, pins and machined parts needing tight tolerance, bright finish and higher yield strength. Yield strength is 265 MPa in HR versus 400 MPa in CD.
Sources
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Machinery's Handbook, 31st ed. — Industrial Press (2020)
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.