Steel Q235A-A (Solution annealed)
Temper
GB Q235A
Use when maximum ductility and lowest hardness are needed for deep forming, or to soften cold-worked stock.
Values for the A condition
Other Q235A tempers and conditions
Q235A is listed in 5 conditions; see the grade overview at Q235A.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AThis page Solution annealed | Use when maximum ductility and lowest hardness are needed for deep forming, or to soften cold-worked stock. | 240 | 385 | 34 | 112 HB | 10.7 % IACS |
Normalized | Pick for thick plate or forgings needing uniform fine-grain structure and better toughness/ductility after hot work. | 250 | 410 | 31 | 121 HB | 10.5 % IACS |
HRDefault Hot rolled | Default stock condition for plate, angle, channel, I-beam and hot-rolled coil in general welded structures. | 255 | 420 | 28 | 131 HB | — |
Cold rolled | Choose for thin gauge sheet parts needing tight thickness tolerance, flat clean surface and paint-ready finish. | 340 | 450 | 16 | 150 HB | 10.2 % IACS |
Cold drawn | Pick for shafts, pins and machined parts where higher yield, straightness and a bright as-drawn surface save machining. | 400 | 510 | 12 | 163 HB | — |
What is Q235A-A?
Q235A-A is Q235A in the A temper — use when maximum ductility and lowest hardness are needed for deep forming, or to soften cold-worked stock. Q235A-A has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 385 MPa (55.8 ksi) — weaker than 96% of steel grades. Elongation at break is 34% and the elastic modulus is 206 GPa (29.9 Msi). Q235A-A 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; A is available on request or by drawing note.
Advantages
- Conducts heat well — 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades
- Forms and bends easily — 90/100, better than 98% of steel grades
- Ductile — tolerates forming and impact — 34%, better than 97% of steel grades
- Readily welded — 94/100, better than 95% of steel grades
- High electrical conductivity — 10.7 % IACS, better than 91% of steel grades
Limitations
- Low strength — 240 MPa (34.8 ksi), worse than 96% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
Q235A-A properties
Typical room-temperature values for Q235A-A; 22 are specific to this condition. Other listed values are Q235A reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
Q235A-A 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
Q235A-A has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 385 MPa (55.8 ksi) — weaker than 96% of steel grades. Elongation at break is 34% and the elastic modulus is 206 GPa (29.9 Msi).
Thermal6
Q235A-A is rated for continuous service to 350°C (662 °F). It conducts heat at 52 W/m·K (30 BTU/hr·ft·°F), better than 98% of steel grades. Thermal expansion is 11.9 µm/m·K (6.61 µin/in·°F).
Electrical3
Q235A-A conducts electricity at 10.7 % IACS, better than 91% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (10/100), worse than 86% of steel grades.
Sustainability4
Producing a kilogram of Q235A-A takes about 25 MJ of energy and emits 2.1 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 20%.
Manufacturability7
Q235A-A's machinability is good (59/100, better than 80% of steel grades); weldability excellent (94/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Q235A-A
Is Q235A easy to machine?
Machines easily but gummy in the hot-rolled state — use positive-rake carbide, high speed and generous coolant; cold-drawn stock gives cleaner chips and better finish.
Can Q235A be welded?
Excellent weldability by SMAW/GMAW/SAW with E43xx (E4303/E4315) or ER70S-6, no preheat below ~30 mm; grade A's high S/P raises hot-cracking risk on thick restrained joints, so prefer Q235B for critical welds.
Can Q235A be formed, bent or molded?
Readily bent, rolled and press-formed cold at bend radii ≥1–1.5 t; hot forming 850–1050 °C, and avoid cold bending below 0 °C.
What surface finishes work on Q235A?
Must be protected — shot-blast then prime/paint, hot-dip galvanize or zinc-plate/phosphate; takes oil-blackening and powder coat well, but polished surfaces rust within hours.
Q235A 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, grade A | 0.14 – 0.22 | 0.18 |
| Si | ≤ 0.35 | 0.2 |
| Mntypically 0.30–0.65 in plate | ≤ 1.4 | 0.5 |
| P | ≤ 0.05 | 0.03 |
| Sloosest S limit of the Q235 quality grades | ≤ 0.05 | 0.03 |
| Fe | balance | — |
Q235A-A — frequently asked
What is Q235A-A used for?
Q235A-A is typically used for building frames and columns, structural beams, angle and channel, welded frames and skids, base plates and gussets, laser-cut sheet parts and enclosures, cabinets and machine guards. In short: chinese mild-steel sheet.
What is the yield strength of Q235A-A?
Q235A-A has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 385 MPa (55.8 ksi) — weaker than 96% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is Q235A-A easy to machine?
Reasonably — machinability is rated good (59/100, better than 80% of steel grades). Machines easily but gummy in the hot-rolled state — use positive-rake carbide, high speed and generous coolant; cold-drawn stock gives cleaner chips and better finish.
Can Q235A-A be welded?
Yes — weldability is rated excellent (94/100). Excellent weldability by SMAW/GMAW/SAW with E43xx (E4303/E4315) or ER70S-6, no preheat below ~30 mm; grade A's high S/P raises hot-cracking risk on thick restrained joints, so prefer Q235B for critical welds.
What surface finishes work on Q235A-A?
Must be protected — shot-blast then prime/paint, hot-dip galvanize or zinc-plate/phosphate; takes oil-blackening and powder coat well, but polished surfaces rust within hours.
Can Q235A-A be formed, bent or molded?
Readily bent, rolled and press-formed cold at bend radii ≥1–1.5 t; hot forming 850–1050 °C, and avoid cold bending below 0 °C.
What is the maximum service temperature of Q235A-A?
Q235A-A 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 Q235A-HR and Q235A-CD?
HR is the default condition — default stock condition for plate, angle, channel, I-beam and hot-rolled coil in general welded structures. CD: pick for shafts, pins and machined parts where higher yield, straightness and a bright as-drawn surface save machining. Yield strength is 255 MPa in HR versus 400 MPa in CD.
Can FabDigit make parts in Q235A-A?
Yes — Q235A-A is available for CNC machining and sheet metal with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels — ASM International (1990)
- ASM Handbook Vol.19: Fatigue and Fracture — ASM International (1996)
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.