Steel A283 Q&T (Quenched and tempered)
Heat-treated state
ASTM A283
Rarely ordered; only worthwhile on thin sections since 0.24 % C max gives shallow hardenability — expect modest strength gain and reduced ductility.
Values for the Q&T condition
Other A283 tempers and conditions
A283 is listed in 9 conditions; see the grade overview at A283.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Grade A | Lowest-strength, lowest-carbon grade; pick for maximum formability and welding ease where strength is irrelevant. | 190 | 350 | 30 | 105 HB | 10.8 % IACS |
full/subcritical anneal for maximum ductility | Choose when severe cold forming or stress relief after heavy welding/flame cutting is required. | 210 | 390 | 30 | 110 HB | 11 % IACS |
Grade B | Intermediate grade between A and C; used where a slightly higher yield is wanted with still very good forming. | 215 | 390 | 28 | 116 HB | 10.5 % IACS |
HRDefault Hot rolled | Standard stock condition for A283 plate — pick for general structural, tank and base-plate work where only mild strength is needed. | 230 | 420 | 25 | 120 HB | 10.8 % IACS |
880–920 °C air cool | Use for uniform fine-grain structure and better notch toughness in thicker plate or after hot forming. | 240 | 425 | 28 | 125 HB | 10.8 % IACS |
Normalized and tempered | Specify when dimensional stability and residual-stress control are needed together with fine-grain toughness. | 250 | 430 | 27 | 130 HB | 10.8 % IACS |
Grade C | Default commercial grade — best balance of strength, weldability and price for tanks and general plate work. | 250 | 430 | 26 | 128 HB | 10.4 % IACS |
Grade D | Highest-strength A283 grade (C up to 0.27 %); choose for the best strength-to-price ratio, accepting lower ductility and a higher carbon equivalent. | 275 | 470 | 24 | 140 HB | 10.1 % IACS |
Q&TThis page Quenched and tempered | Rarely ordered; only worthwhile on thin sections since 0.24 % C max gives shallow hardenability — expect modest strength gain and reduced ductility. | 370 | 520 | 22 | 155 HB | 10.5 % IACS |
What is A283 Q&T?
A283 Q&T is A283 heat treated to Q&T — rarely ordered; only worthwhile on thin sections since 0.24 % C max gives shallow hardenability — expect modest strength gain and reduced ductility. A283 Q&T has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 70% of steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi). A283 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F). HR is the default condition FabDigit quotes; Q&T is available on request or by drawing note.
Advantages
- Low embodied carbon — 1.9 kg CO₂/kg, better than 92% of steel grades
- High electrical conductivity — 10.5 % IACS, better than 89% of steel grades
- Readily welded — 88/100, better than 87% of steel grades
- Conducts heat well — 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades
- Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 81% of steel grades
Limitations
- Hard to polish — 45/100, worse than 84% of steel grades
A283 Q&T properties
Typical room-temperature values for A283 Q&T; 22 are specific to this condition. Other listed values are A283 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A283 Q&T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical16
A283 Q&T has a yield strength of 370 MPa (53.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 70% of steel grades. Elongation at break is 22% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
A283 Q&T is rated for continuous service to 375°C (707 °F). It conducts heat at 49 W/m·K (28.3 BTU/hr·ft·°F), better than 83% of steel grades. Thermal expansion is 11.7 µm/m·K (6.5 µin/in·°F).
Electrical3
A283 Q&T conducts electricity at 10.5 % IACS, better than 89% of steel grades.
Chemical & Environmental3
Corrosion resistance is not recommended (11/100), worse than 73% of steel grades.
Sustainability4
Producing a kilogram of A283 Q&T takes about 25 MJ of energy and emits 1.9 kg of CO₂ — less than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
A283 Q&T's machinability is good (57/100, better than 71% of steel grades); weldability excellent (88/100); formability good (60/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A283 Q&T
Is A283 easy to machine?
Machines like AISI 1020 (≈70 % of 1212): free-flowing gummy chips, use sharp positive-rake tooling, generous feed and coolant to avoid built-up edge.
Can A283 be welded?
Excellent weldability with SMAW/GMAW/FCAW/SAW using E70xx-class consumables; no preheat needed for thin plate, 50–100 °C preheat prudent for Grade D or >32 mm.
Can A283 be formed, bent or molded?
Good cold bending and rolling (bend radius ≈2t for Grades A–C, 2.5–3t for D); hot form 900–1200 °C, avoid working in the 200–400 °C blue-brittle range.
What surface finishes work on A283?
Descale/blast off mill scale, then zinc-rich primer, paint, phosphate or hot-dip galvanizing; no anodizing, bare steel rusts quickly.
A283 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 |
|---|---|---|
| Cmax by grade for ≤20 mm plate: A 0.14, B 0.17, C 0.24, D 0.27; limits rise with thickness | ≤ 0.24 | 0.18 |
| Mn0.90 max (Grades C/D); heat analysis | ≤ 0.9 | 0.6 |
| Si0.40 max when killed/semi-killed practice reported | ≤ 0.4 | 0.2 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.04 | 0.02 |
| Cu0.20 min only when copper-bearing steel is specified | ≥ 0.2 | 0.25 |
| Fe | balance |
A283 Q&T — frequently asked
What is A283 Q&T used for?
A283 Q&T is typically used for storage tanks, low-pressure vessel shells, base plates and gussets, machine bases and frames, hoppers and chutes and structural brackets and supports. In short: low-cost structural plate.
What is the yield strength of A283 Q&T?
A283 Q&T has a typical yield strength of 370 MPa (53.7 ksi) and a tensile strength of 520 MPa (75.4 ksi) — weaker than 70% of steel grades. Strength varies by condition: see the 9 listed tempers.
Is A283 Q&T easy to machine?
Reasonably — machinability is rated good (57/100, better than 71% of steel grades). Machines like AISI 1020 (≈70 % of 1212): free-flowing gummy chips, use sharp positive-rake tooling, generous feed and coolant to avoid built-up edge.
Can A283 Q&T be welded?
Yes — weldability is rated excellent (88/100). Excellent weldability with SMAW/GMAW/FCAW/SAW using E70xx-class consumables; no preheat needed for thin plate, 50–100 °C preheat prudent for Grade D or >32 mm.
What surface finishes work on A283 Q&T?
Descale/blast off mill scale, then zinc-rich primer, paint, phosphate or hot-dip galvanizing; no anodizing, bare steel rusts quickly.
Can A283 Q&T be formed, bent or molded?
Good cold bending and rolling (bend radius ≈2t for Grades A–C, 2.5–3t for D); hot form 900–1200 °C, avoid working in the 200–400 °C blue-brittle range.
What is the maximum service temperature of A283 Q&T?
A283 Q&T is rated for continuous use to about 375°C (707 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A283-HR and A283-GrD?
HR is the default condition — standard stock condition for A283 plate — pick for general structural, tank and base-plate work where only mild strength is needed. GrD: highest-strength A283 grade (C up to 0.27 %); choose for the best strength-to-price ratio, accepting lower ductility and a higher carbon equivalent. Yield strength is 230 MPa in HR versus 275 MPa in GrD.
Can FabDigit make parts in A283 Q&T?
Yes — A283 Q&T 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
- ASTM A283/A283M — Standard Specification for Low and Intermediate Tensile Strength Carbon Steel Plates — ASTM International (2018)
- ASTM A6/A6M — General Requirements for Rolled Structural Steel Bars, Plates, Shapes and Sheet Piling — ASTM International (2019)
- ASM Handbook Vol. 1: Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol. 13B: Corrosion — Materials — ASM International (2005)
- ASME BPVC Section II Part D — Material Properties (physical property tables, carbon steel) — ASME (2023)
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.