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Steel 1040 vs A321

Steel · grade comparison

Steel 1040 and A321 are both steel grades. 1040 is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 305 MPa (44.2 ksi) for A321, about 36% more; tensile strength follows at 620 MPa (89.9 ksi) vs 550 MPa (79.8 ksi). 1040 is the more ductile: elongation 25% versus 18% for A321, and 1040 is harder (201 HB vs 163 HB).

1040Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

1040 vs A321: properties

1040A321

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

620 MPa89.9 ksi
550 MPa79.8 ksi

Yield Strength (0.2% offset)

415 MPa60.2 ksi
305 MPa44.2 ksi

Elongation at Break

25%
18%

Reduction in Area

50%
40%

Compressive Strength

415 MPa60.2 ksi
310 MPa45 ksi

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

201 HB
163 HB

Hardness, Rockwell B

93 HRB
84 HRB

Hardness, Vickers

210 HV
172 HV

Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Shear Strength 385 MPa55.8 ksi · Fracture Toughness (K_IC) 55 MPa·√m50.1 ksi·√in

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,495°C2,723 °F

Thermal

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

Thermal Conductivity

51 W/m·K29.5 BTU/hr·ft·°F
50 W/m·K28.9 BTU/hr·ft·°F

Specific Heat Capacity

486 J/kg·K0.12 BTU/lb·°F
477 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

11.5 µm/m·K6.4 µin/in·°F
11.7 µm/m·K6.5 µin/in·°F

Max Service Temperature (continuous)

425°C797 °F
400°C752 °F

Same in both: Latent Heat of Fusion 247 J/g106 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
10.5 % IACS

Electrical Resistivity

1.71×10⁻⁷ Ω·m6.73 µΩ·in
1.65×10⁻⁷ Ω·m6.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.61 V
-0.65 V

Same in both: Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

55 / 100
58 / 100

Weldability

45 / 100
48 / 100

Brazeability / Solderability

60 / 100
65 / 100

Polishability

60 / 100
55 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 60% · Formability (cold) 45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

2.1 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

50 L/kg6 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

25%
28%

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

79 kN·m/kg
70 kN·m/kg

Modulus of Resilience

420 kJ/m³
227 kJ/m³

Thermal Shock Resistance Index

13
11

Same in both: Specific Stiffness (E / density) 26.1 MN·m/kg · Thermal Diffusivity 13.4 mm²/s

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 scale1040A321

Manufacturing and finishing

Capability1040A321
CNC machiningYes—
Sheet metalYes—
Default conditionHR—
Relative cost$ Budget$ 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.

1040 vs A321 — frequently asked

Is 1040 stronger than A321?

Yes. 1040 has a typical yield strength of 415 MPa (60.2 ksi) against 305 MPa (44.2 ksi) for A321 — about 36% more. Tensile strength is 620 MPa (89.9 ksi) vs 550 MPa (79.8 ksi).

Which is cheaper, 1040 or A321?

Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.

When should I choose 1040 over A321?

Pick 1040 when strength drives the design, or when the part is bent, formed or impact-loaded.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1040 and A321 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.