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Steel A285 vs A372 Grade B

Steel · grade comparison

Steel A285 and A372 Grade B are both steel grades. A372 Grade B is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 250 MPa (36.3 ksi) for A285, about 88% more; tensile strength follows at 655 MPa (95 ksi) vs 450 MPa (65.3 ksi). In exchange, A285 is the more ductile: elongation 30% versus 22% for A372 Grade B, and A372 Grade B is harder (197 HB vs 130 HB). On the shop floor, A285 machines more easily (68 vs 55 out of 100), A285 welds better (excellent vs good), and A372 Grade B sits in a lower cost tier (budget, $) than A285 (standard, $$).

A285Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

A372 Grade BChoose it when strength drives the design, or when cost is the deciding factor.

A285 vs A372 Grade B: properties

A285A372 Grade B

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
205 GPa29.7 Msi

Shear Modulus

79 GPa11.5 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

450 MPa65.3 ksi
655 MPa95 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
470 MPa68.2 ksi

Elongation at Break

30%
22%

Reduction in Area

55%
50%

Compressive Strength

250 MPa36.3 ksi
450 MPa65.3 ksi

Shear Strength

290 MPa42.1 ksi
385 MPa55.8 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
295 MPa42.8 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
48 J35.4 ft·lbf

Hardness, Brinell

130 HB
197 HB

Hardness, Rockwell B

72 HRB
93 HRB

Hardness, Vickers

—
207 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,460°C2,660 °F
1,425°C2,597 °F

Liquidus Temperature

1,515°C2,759 °F
1,500°C2,732 °F

Same in both: Density 7.85 g/cm³0.28 lb/in³

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

51 W/m·K29.5 BTU/hr·ft·°F
48 W/m·K27.7 BTU/hr·ft·°F

Max Service Temperature (continuous)

425°C797 °F
400°C752 °F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -29°C-20 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10.8 % IACS
10 % IACS

Electrical Resistivity

1.6×10⁻⁷ Ω·m6.3 µΩ·in
1.7×10⁻⁷ Ω·m6.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.62 V
-0.61 V

Same in both: Corrosion Resistance 10 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

68 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
60%

Weldability

92 / 100
55 / 100

Formability (cold)

82 / 100
40 / 100

Brazeability / Solderability

60 / 100
55 / 100

Polishability

40 / 100
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

30 L/kg3.6 gal/lb
60 L/kg7.2 gal/lb

Typical Recycled Content

25%
30%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

57 kN·m/kg
83 kN·m/kg

Specific Stiffness (E / density)

25.5 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

156 kJ/m³
539 kJ/m³

Thermal Diffusivity

13.8 mm²/s
13 mm²/s

Thermal Shock Resistance Index

10
13

Strength versus weight

Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scaleA285A372 Grade B

Manufacturing and finishing

CapabilityA285A372 Grade B
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$$ Standard$ Budget
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
E-CoatingYes—
HVOF CoatingYes—
Hot-Dip GalvanizingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

A285 vs A372 Grade B — frequently asked

Is A372 Grade B stronger than A285?

Yes. A372 Grade B has a typical yield strength of 470 MPa (68.2 ksi) against 250 MPa (36.3 ksi) for A285 — about 88% more. Tensile strength is 655 MPa (95 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, A285 or A372 Grade B?

A372 Grade B is the lower-cost material: it sits in the budget tier ($) while A285 is standard ($$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, A285 or A372 Grade B?

A285, by a small margin. Both rate good for machinability — 68/100 against 55/100 for A372 Grade B; for welding the order is A285 first (excellent, 92/100) then A372 Grade B (good, 55/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A285 and A372 Grade B side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.

Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.