Steel A202
ASTM A202
A chromium-manganese-silicon alloy steel plate specification historically used for pressure vessels needing higher strength than carbon steel plates, now largely superseded by A387 chrome-moly grades.
Reference datasheet — A202 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 GrA condition
A202 tempers and conditions
A202 is supplied in 2 conditions, soft to hard. GrA is the default FabDigit quotes; the values on this page are for it.
Compare all 2 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
GrADefault Grade A | Pick when 515–655 MPa tensile with the best weldability and toughness of the two levels is wanted; supplied as-rolled or normalized. | 350 | 570 | 24 | 163 HB | 40 W/m·K |
Grade B | Pick when higher allowable stress (585–725 MPa tensile) is needed and the extra carbon's preheat/PWHT demands are acceptable. | 390 | 640 | 21 | 187 HB | 39 W/m·K |
What is A202?
A chromium-manganese-silicon alloy steel plate specification historically used for pressure vessels needing higher strength than carbon steel plates, now largely superseded by A387 chrome-moly grades. A202 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). A202 has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 74% of steel grades. Elongation at break is 24% and the elastic modulus is 203 GPa (29.4 Msi).
What is A202 used for?
- Pressure vessel shells
- Boiler drums
- Storage tank plates for higher-strength service
Advantages
- High service temperature — 450°C (842 °F), better than 86% of steel grades
A202 properties
Typical room-temperature values for A202-GrA; bars are the position among steel grades.
Physical3
A202 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
A202 has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 74% of steel grades. Elongation at break is 24% and the elastic modulus is 203 GPa (29.4 Msi).
Thermal6
A202 is rated for continuous service to 450°C (842 °F). It conducts heat at 40 W/m·K (23.1 BTU/hr·ft·°F), worse than 64% of steel grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
A202 conducts electricity at 7.5 % IACS, worse than 67% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (15/100), better than 75% of steel grades.
Sustainability4
Producing a kilogram of A202 takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.
Manufacturability7
A202's machinability is good (58/100, better than 75% of steel grades); weldability good (65/100); formability good (60/100).
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. A202 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A202
Is A202 easy to machine?
Machines like a 190 HB low-alloy plate — carbide tooling, moderate speeds; the ~0.75 % Si makes chips gummier than plain carbon steel.
Can A202 be welded?
Weldable with low-hydrogen SMAW/SAW consumables but preheat 100–200 °C and PWHT at 595–650 °C are normally specified, especially for Grade B and thick sections.
Can A202 be formed, bent or molded?
Cold-roll shells with generous bend radii; hot forming 900–1000 °C followed by re-normalizing is preferred for heads and heavy plate.
A202 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 |
|---|---|---|
| CGrade A; Grade B up to 0.25 % (heavier plate limits per A202) | ≤ 0.17 | 0.15 |
| Mn | 1.05 – 1.4 | 1.2 |
| Sisolid-solution strengthener, raises weld hardenability | 0.6 – 0.9 | 0.75 |
| Cr | 0.35 – 0.6 | 0.48 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.04 | 0.01 |
| Fe | balance | — |
What surface finishes work on A202?
No inherent corrosion resistance — blast to Sa 2.5 and apply epoxy/inorganic-zinc coating, weld-overlay or clad for wet service.
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 A202 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A202 Gr AA202 Gr B
How much does A202 cost?
A202 is a budget-cost steel ($), cheaper than about 90% 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.
A202 — frequently asked
What is A202 used for?
A202 is typically used for pressure vessel shells, boiler drums and storage tank plates for higher-strength service. In short: legacy Cr-Mn-Si vessel plate; stronger than carbon plate; superseded by A387 grades.
What is the yield strength of A202?
A202 has a typical yield strength of 350 MPa (50.8 ksi) and a tensile strength of 570 MPa (82.7 ksi) — weaker than 74% of steel grades. Strength varies by condition: see the 2 listed tempers.
Is A202 easy to machine?
Reasonably — machinability is rated good (58/100, better than 75% of steel grades). Machines like a 190 HB low-alloy plate — carbide tooling, moderate speeds; the ~0.75 % Si makes chips gummier than plain carbon steel.
Can A202 be welded?
Yes — weldability is rated good (65/100). Weldable with low-hydrogen SMAW/SAW consumables but preheat 100–200 °C and PWHT at 595–650 °C are normally specified, especially for Grade B and thick sections.
What surface finishes work on A202?
No inherent corrosion resistance — blast to Sa 2.5 and apply epoxy/inorganic-zinc coating, weld-overlay or clad for wet service.
Can A202 be formed, bent or molded?
Cold-roll shells with generous bend radii; hot forming 900–1000 °C followed by re-normalizing is preferred for heads and heavy plate.
What is the maximum service temperature of A202?
A202 is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A202-GrA and A202-GrB?
GrA is the default condition — pick when 515–655 MPa tensile with the best weldability and toughness of the two levels is wanted; supplied as-rolled or normalized. GrB: pick when higher allowable stress (585–725 MPa tensile) is needed and the extra carbon's preheat/PWHT demands are acceptable. Yield strength is 350 MPa in GrA versus 390 MPa in GrB.
How much does A202 cost?
A202 is a budget-cost steel ($), cheaper than about 90% 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 A202/A202M — Pressure Vessel Plates, Alloy Steel, Chromium-Manganese-Silicon — ASTM International (2019)
- ASTM A20/A20M — General Requirements for Steel Plates for Pressure Vessels — ASTM International (2020)
- ASME BPVC Section II Part D — Materials, Properties — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — 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; 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.