Steel A356 Grade 2
ASTM A356 Grade 2 · UNS J12523
ASTM A356 Grade 2 (UNS J12523) is a carbon-1/2Mo low-alloy steel casting used for heavy-wall turbine and pressure-vessel components that need moderate elevated-temperature strength.
Reference datasheet — A356 Grade 2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the N+T condition
A356 Grade 2 tempers and conditions
A356 Grade 2 is supplied in 4 conditions, soft to hard. N+T is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
full anneal (furnace cooled) | Chosen for very thick sections or when maximum machinability, dimensional stability and low residual stress matter more than strength. | 275 | 500 | 29 | 143 HB | 9 % IACS |
N+T + PWHT / stress relieved | Condition delivered after weld repair of the casting or after fabrication welding; post-weld heat treatment restores toughness in the HAZ. | 295 | 510 | 25 | 150 HB | 9 % IACS |
N+TDefault Normalized and tempered | Standard supply condition for heavy-wall turbine/valve castings: best combination of strength, toughness and creep behaviour. | 305 | 525 | 26 | 155 HB | 9 % IACS |
Quenched and tempered | Used when the purchaser wants the upper end of the strength/toughness band in moderate wall thicknesses; needs a high temper to stay within the specified yield range. | 370 | 570 | 24 | 175 HB | 8.5 % IACS |
What is A356 Grade 2?
ASTM A356 Grade 2 (UNS J12523) is a carbon-1/2Mo low-alloy steel casting used for heavy-wall turbine and pressure-vessel components that need moderate elevated-temperature strength. In the normalized-and-tempered condition it provides about 305 MPa yield, 525 MPa tensile, 26 % elongation and 155 HB, with service up to 470 °C; annealed, quenched-and-tempered and normalize-temper-stress-relieve conditions are also supplied. It is a casting grade only, weld repairs need preheat and PWHT, and it has no corrosion resistance. Where higher creep strength is required, a Cr-Mo casting such as A217 WC6 is the usual step up. A356 Grade 2 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,440°C (2,624 °F). A356 Grade 2 has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 525 MPa (76.1 ksi) — weaker than 84% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
What is A356 Grade 2 used for?
- steam turbine casings
- valve bodies
- pressure vessel heads
Advantages
- High service temperature — 470°C (878 °F), better than 87% of steel grades
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
Limitations
- Limited formability — 15/100, worse than 87% of steel grades
- Low strength — 305 MPa (44.2 ksi), worse than 84% of steel grades
- Hard to polish — 45/100, worse than 84% of steel grades
A356 Grade 2 properties
Typical room-temperature values for A356 Grade 2-N+T; bars are the position among steel grades.
Physical3
A356 Grade 2 has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,440°C (2,624 °F).
Mechanical16
A356 Grade 2 has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 525 MPa (76.1 ksi) — weaker than 84% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
A356 Grade 2 is rated for continuous service to 470°C (878 °F). It conducts heat at 42 W/m·K (24.3 BTU/hr·ft·°F), worse than 56% of steel grades. Thermal expansion is 12.2 µm/m·K (6.78 µin/in·°F).
Electrical3
A356 Grade 2 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 A356 Grade 2 takes about 30 MJ of energy and emits 2.2 kg of CO₂ — more than 56% of steel grades. Typical recycled content is 80%.
Manufacturability7
A356 Grade 2's machinability is good (55/100, better than 62% of steel grades); weldability good (65/100); formability poor (15/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. A356 Grade 2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A356 Grade 2
Is A356 Grade 2 easy to machine?
Machines like normalized 4130-class steel at ~60 % of 1212; use rigid setups, carbide inserts and expect harder skin/chill zones on casting surfaces.
Can A356 Grade 2 be welded?
Readily welded with matched C-1/2Mo consumables (E7018-A1 / ER80S-D2); preheat 150–200 °C and PWHT at 620–680 °C for weld repairs and thick sections.
Can A356 Grade 2 be formed, bent or molded?
Sand-cast product with good fluidity; heavy walls need generous risering, chills and controlled solidification to avoid shrinkage porosity and hot tears.
A356 Grade 2 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 |
|---|---|---|
| Ccarbon | ≤ 0.25 | 0.22 |
| Si | ≤ 0.6 | 0.4 |
| Mn | ≤ 0.7 | 0.6 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.02 |
| Moprovides elevated-temperature strength | 0.45 – 0.65 | 0.55 |
| Fe | balance | — |
What surface finishes work on A356 Grade 2?
Not anodizable; protect by shot blast plus epoxy/aluminium metallizing, or leave bare inside dry-steam service where oxide film is stable.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel A356 Grade 2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- J12523
How much does A356 Grade 2 cost?
A356 Grade 2 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
A356 Grade 2 — frequently asked
What is A356 Grade 2 used for?
A356 Grade 2 is typically used for steam turbine casings, valve bodies and pressure vessel heads. In short: C-1/2Mo pressure casting; heavy-wall turbine grade; service to 470 °C.
What is the yield strength of A356 Grade 2?
A356 Grade 2 has a typical yield strength of 305 MPa (44.2 ksi) and a tensile strength of 525 MPa (76.1 ksi) — weaker than 84% of steel grades. Strength varies by condition: see the 4 listed tempers.
Is A356 Grade 2 easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). Machines like normalized 4130-class steel at ~60 % of 1212; use rigid setups, carbide inserts and expect harder skin/chill zones on casting surfaces.
Can A356 Grade 2 be welded?
Yes — weldability is rated good (65/100). Readily welded with matched C-1/2Mo consumables (E7018-A1 / ER80S-D2); preheat 150–200 °C and PWHT at 620–680 °C for weld repairs and thick sections.
What surface finishes work on A356 Grade 2?
Not anodizable; protect by shot blast plus epoxy/aluminium metallizing, or leave bare inside dry-steam service where oxide film is stable.
Can A356 Grade 2 be formed, bent or molded?
Sand-cast product with good fluidity; heavy walls need generous risering, chills and controlled solidification to avoid shrinkage porosity and hot tears.
What is the maximum service temperature of A356 Grade 2?
A356 Grade 2 is rated for continuous use to about 470°C (878 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does A356 Grade 2 cost?
A356 Grade 2 is a standard-cost steel ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM A356/A356M — Steel Castings, Carbon, Low Alloy, and Stainless Steel, Heavy-Walled for Steam Turbines — ASTM International (2021)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- Steel Castings Handbook, 6th ed. — Steel Founders' Society of America / ASM (1995)
- ASME BPVC Section II Part D — Material Properties (C-1/2Mo) — ASME (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.