FabDigitFabDigit

Steel A369 FP91 vs A514

Steel · grade comparison

Steel A369 FP91 and A514 are both steel grades. A514 is the stronger of the two: yield strength 760 MPa (110 ksi) against 500 MPa (72.5 ksi) for A369 FP91, about 52% more; tensile strength follows at 800 MPa (116 ksi) vs 660 MPa (95.7 ksi). In exchange, A369 FP91 is the more ductile: elongation 23% versus 19% for A514, and A514 is harder (250 HB vs 210 HB). A369 FP91 is stiffer (218 GPa vs 205 GPa) and A369 FP91 runs hotter in service (600°C vs 400°C continuous). On the shop floor, A514 welds better (good vs fair).

A369 FP91Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

A514Choose it when strength drives the design, or when it will be welded.

A369 FP91 vs A514: properties

A369 FP91A514

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

218 GPa31.6 Msi
205 GPa29.7 Msi

Shear Modulus

84 GPa12.2 Msi
80 GPa11.6 Msi

Bulk Modulus

180 GPa26.1 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

660 MPa95.7 ksi
800 MPa116 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
760 MPa110 ksi

Elongation at Break

23%
19%

Reduction in Area

62%
50%

Compressive Strength

510 MPa74 ksi
760 MPa110 ksi

Shear Strength

400 MPa58 ksi
480 MPa69.6 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
380 MPa55.1 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
120 MPa·√m109 ksi·√in

Charpy V-Notch Impact (RT)

130 J95.9 ft·lbf
75 J55.3 ft·lbf

Hardness, Brinell

210 HB
250 HB

Hardness, Rockwell C

18 HRC
24 HRC

Hardness, Vickers

220 HV
262 HV

Hardness, Rockwell B

—
100 HRB

Physical

Density and transition temperatures.

Density

7.77 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,450°C2,642 °F
1,425°C2,597 °F

Liquidus Temperature

1,500°C2,732 °F
1,510°C2,750 °F

Thermal

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

Thermal Conductivity

26 W/m·K15 BTU/hr·ft·°F
42 W/m·K24.3 BTU/hr·ft·°F

Specific Heat Capacity

480 J/kg·K0.11 BTU/lb·°F
470 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
12 µm/m·K6.7 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
250 J/g107 BTU/lb

Max Service Temperature (continuous)

600°C1,112 °F
400°C752 °F

Min Service Temperature

-30°C-22 °F
-45°C-49 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
7 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
2.4×10⁻⁷ Ω·m9.45 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.58 V
-0.6 V

Corrosion Resistance

30 / 100
16 / 100

Manufacturability

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

Machinability

45 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
40%

Weldability

40 / 100
55 / 100

Castability

45 / 100
—

Brazeability / Solderability

35 / 100
40 / 100

Polishability

60 / 100
50 / 100

Same in both: Formability (cold) 30 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

34 MJ/kg14,617 BTU/lb
31 MJ/kg13,328 BTU/lb

Embodied Carbon (primary production)

2.5 kg CO₂/kg
2.4 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

25%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
102 kN·m/kg

Specific Stiffness (E / density)

28.1 MN·m/kg
26.1 MN·m/kg

Modulus of Resilience

573 kJ/m³
1,409 kJ/m³

Thermal Diffusivity

7 mm²/s
11.4 mm²/s

Thermal Shock Resistance Index

7
14

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 scaleA514A369 FP91

Manufacturing and finishing

CapabilityA369 FP91A514
CNC machining—Yes
Sheet metal—Yes
Default condition—Q&T
Relative cost$$ Standard$$ Standard
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

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

A369 FP91 vs A514 — frequently asked

Is A514 stronger than A369 FP91?

Yes. A514 has a typical yield strength of 760 MPa (110 ksi) against 500 MPa (72.5 ksi) for A369 FP91 — about 52% more. Tensile strength is 800 MPa (116 ksi) vs 660 MPa (95.7 ksi).

Which is cheaper, A369 FP91 or A514?

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

Which is easier to machine, A369 FP91 or A514?

A369 FP91, by a small margin. Both rate fair for machinability — 45/100 against 38/100 for A514; for welding the order is A514 first (good, 55/100) then A369 FP91 (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in A369 FP91 and A514 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.