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Steel A202-GrA

Grade · default condition

ASTM A202

GrA = 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.

Budget cost $

Values for the GrA condition

Other A202 tempers and conditions

A202 is listed in 2 conditions; see the grade overview at A202.

Compare all 2 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
GrADefaultThis page
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.35057024163 HB40 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.39064021187 HB39 W/m·K

What is A202-GrA?

A202-GrA is A202 in the GrA grade — pick when 515–655 MPa tensile with the best weldability and toughness of the two levels is wanted; supplied as-rolled or normalized. A202-GrA 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). A202-GrA 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).

Advantages

  • High service temperature — 450°C (842 °F), better than 86% of steel grades

A202-GrA properties

Typical room-temperature values for A202-GrA; 34 are specific to this condition. Other listed values are A202 reference data and may not represent this condition. Bars are the position among steel grades.

Physical3

A202-GrA 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).

Density7.85 g/cm³0.28 lb/in³
Melting Point (Solidus)1,425°C2,597 °F
Liquidus Temperature1,500°C2,732 °F

Mechanical16

A202-GrA 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).

Elastic (Young's) Modulus203 GPa29.4 Msi
Shear Modulus79 GPa11.5 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)570 MPa82.7 ksi
Yield Strength (0.2% offset)350 MPa50.8 ksi
Elongation at Break24%
Reduction in Area50%
Compressive Strength340 MPa49.3 ksi
Shear Strength380 MPa55.1 ksi
Fatigue Strength (Endurance Limit)260 MPa37.7 ksi
Fracture Toughness (K_IC)95 MPa·√m86.5 ksi·√in
Charpy V-Notch Impact (RT)45 J33.2 ft·lbf
Hardness, Brinell163 HB
Hardness, Rockwell B84 HRB
Hardness, Vickers175 HV

Thermal6

A202-GrA 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).

Thermal Conductivity40 W/m·K23.1 BTU/hr·ft·°F
Specific Heat Capacity470 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)12 µm/m·K6.7 µin/in·°F
Latent Heat of Fusion270 J/g116 BTU/lb
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-29°C-20 °F

Electrical3

A202-GrA conducts electricity at 7.5 % IACS, worse than 67% of steel grades.

Electrical Conductivity7.5 % IACS
Electrical Resistivity2.3×10⁻⁷ Ω·m9.06 µΩ·in
Magnetic Responseferromagnetic

Chemical & Environmental3

Corrosion resistance is poor (15/100), better than 75% of steel grades.

Galvanic Potential (seawater, vs SCE)-0.62 V
Corrosion ResistancePoor15/100
Chemical Resistance SummaryRusts freely in moist air and water; needs paint, cladding or internal lining. Modest Cr/Si content gives only marginal improvement over carbon steel; not for wet H2S or acid service without protection.

Sustainability4

Producing a kilogram of A202-GrA takes about 26 MJ of energy and emits 2 kg of CO₂ — less than 64% of steel grades. Typical recycled content is 30%.

Embodied Energy (primary production)26 MJ/kg11,178 BTU/lb
Embodied Carbon (primary production)2 kg CO₂/kg
Embodied Water40 L/kg4.8 gal/lb
Typical Recycled Content30%

Manufacturability7

A202-GrA's machinability is good (58/100, better than 75% of steel grades); weldability good (65/100); formability good (60/100).

MachinabilityGood58/100
Machinability Rating (AISI 1212 = 100 %)60%
WeldabilityGood65/100
Formability (cold)Good60/100
Brazeability / SolderabilityFair45/100
PolishabilityFair50/100
Anodizing Responsen/a — ferrous alloy; use paint, metallizing, weld-overlay cladding or galvanizing instead

Common Calculations5

Specific Strength (UTS / density)calculated73 kN·m/kg
Specific Stiffness (E / density)calculated25.9 MN·m/kg
Modulus of Resiliencecalculated302 kJ/m³
Thermal Diffusivitycalculated10.8 mm²/s
Thermal Shock Resistance Indexcalculated9

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with A202-GrA

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.

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.

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.

ElementSpec limit (wt %)Nominal
CGrade A; Grade B up to 0.25 % (heavier plate limits per A202)≤ 0.170.15
Mn1.05 – 1.41.2
Sisolid-solution strengthener, raises weld hardenability0.6 – 0.90.75
Cr0.35 – 0.60.48
P≤ 0.040.02
S≤ 0.040.01
Febalance—

A202-GrA — frequently asked

What is A202-GrA used for?

A202-GrA 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-GrA?

A202-GrA 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-GrA 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-GrA 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-GrA?

No inherent corrosion resistance — blast to Sa 2.5 and apply epoxy/inorganic-zinc coating, weld-overlay or clad for wet service.

Can A202-GrA 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-GrA?

A202-GrA 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.

Sources

  1. ASTM A202/A202M — Pressure Vessel Plates, Alloy Steel, Chromium-Manganese-Silicon — ASTM International (2019)
  2. ASTM A20/A20M — General Requirements for Steel Plates for Pressure Vessels — ASTM International (2020)
  3. ASME BPVC Section II Part D — Materials, Properties — ASME (2023)
  4. ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
  5. 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.