FabDigit

Aluminum AC7A vs AC2A vs AC2B vs AC3A

Benchmark · 4 materials

Side-by-side benchmark of 4 aluminum grades.

AC7A vs AC2A and 2 more: properties

AC7AAC2AAC2BAC3A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

71 GPa10.3 Msi
74 GPa10.7 Msi
74 GPa10.7 Msi
71 GPa10.3 Msi

Shear Modulus

26.5 GPa3.8 Msi
27.5 GPa4 Msi
28 GPa4.1 Msi
26.5 GPa3.8 Msi

Bulk Modulus

69 GPa10 Msi
72 GPa10.4 Msi
71 GPa10.3 Msi
70 GPa10.2 Msi

Tensile Strength (Ultimate)

170 MPa24.7 ksi
250 MPa36.3 ksi
180 MPa26.1 ksi
165 MPa23.9 ksi

Yield Strength (0.2% offset)

85 MPa12.3 ksi
170 MPa24.7 ksi
110 MPa16 ksi
75 MPa10.9 ksi

Elongation at Break

9%
2%
2%
6%

Compressive Strength

90 MPa13.1 ksi
115 MPa16.7 ksi

Shear Strength

110 MPa16 ksi
165 MPa23.9 ksi
145 MPa21 ksi
115 MPa16.7 ksi

Fatigue Strength (Endurance Limit)

50 MPa7.3 ksi
75 MPa10.9 ksi
70 MPa10.2 ksi
55 MPa8 ksi

Charpy V-Notch Impact (RT)

12 J8.9 ft·lbf
3 J2.2 ft·lbf
4 J3 ft·lbf
3 J2.2 ft·lbf

Hardness, Brinell

50 HB
85 HB
70 HB
50 HB

Fracture Toughness (K_IC)

18 MPa·√m16.4 ksi·√in
17 MPa·√m15.5 ksi·√in
15 MPa·√m13.7 ksi·√in

Same in both: Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Density

2.65 g/cm³0.1 lb/in³
2.79 g/cm³0.1 lb/in³
2.77 g/cm³0.1 lb/in³
2.66 g/cm³0.1 lb/in³

Melting Point (Solidus)

599°C1,110 °F
516°C961 °F
516°C961 °F
574°C1,065 °F

Liquidus Temperature

638°C1,180 °F
604°C1,119 °F
604°C1,119 °F
582°C1,080 °F

Thermal

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

Thermal Conductivity

138 W/m·K79.7 BTU/hr·ft·°F
110 W/m·K63.6 BTU/hr·ft·°F
109 W/m·K63 BTU/hr·ft·°F
130 W/m·K75.1 BTU/hr·ft·°F

Specific Heat Capacity

900 J/kg·K0.21 BTU/lb·°F
963 J/kg·K0.23 BTU/lb·°F
963 J/kg·K0.23 BTU/lb·°F
963 J/kg·K0.23 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

24.3 µm/m·K13.5 µin/in·°F
21.5 µm/m·K11.9 µin/in·°F
21.5 µm/m·K11.9 µin/in·°F
20.5 µm/m·K11.4 µin/in·°F

Latent Heat of Fusion

390 J/g168 BTU/lb
389 J/g167 BTU/lb
389 J/g167 BTU/lb
389 J/g167 BTU/lb

Max Service Temperature (continuous)

120°C248 °F
175°C347 °F
150°C302 °F
150°C302 °F

Same in both: Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

35 % IACS
27 % IACS
27 % IACS
33 % IACS

Electrical Resistivity

4.9×10⁻⁸ Ω·m1.93 µΩ·in
6.4×10⁻⁸ Ω·m2.52 µΩ·in
6.4×10⁻⁸ Ω·m2.52 µΩ·in
5.2×10⁻⁸ Ω·m2.05 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.87 V
-0.75 V
-0.81 V
-0.83 V

Corrosion Resistance

78 / 100
42 / 100
42 / 100
58 / 100

Manufacturability

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

Machinability

70 / 100
72 / 100
65 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

110%
70%
130%
30%

Weldability

80 / 100
35 / 100
35 / 100
80 / 100

Castability

35 / 100
75 / 100
85 / 100
95 / 100

Brazeability / Solderability

15 / 100
25 / 100
20 / 100
35 / 100

Polishability

90 / 100
40 / 100
40 / 100
45 / 100

Formability (cold)

10 / 100
5 / 100
10 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

12.5 kg CO₂/kg
12 kg CO₂/kg
12 kg CO₂/kg
12 kg CO₂/kg

Embodied Water

1,150 L/kg138 gal/lb
1,150 L/kg138 gal/lb
1,150 L/kg138 gal/lb
1,200 L/kg144 gal/lb

Typical Recycled Content

55%
80%
85%
70%

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

64 kN·m/kg
90 kN·m/kg
65 kN·m/kg
62 kN·m/kg

Specific Stiffness (E / density)

26.8 MN·m/kg
26.5 MN·m/kg
26.7 MN·m/kg
26.7 MN·m/kg

Modulus of Resilience

51 kJ/m³
195 kJ/m³
82 kJ/m³
40 kJ/m³

Thermal Diffusivity

57.9 mm²/s
40.9 mm²/s
40.9 mm²/s
50.7 mm²/s

Thermal Shock Resistance Index

14
17
12
15

Strength versus weight

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

20501002005002.22.42.62.83Density (g/cm³)Yield strength (MPa) — log scaleAC2AAC2BAC3AAC7A

Manufacturing and finishing

CapabilityAC7AAC2AAC2BAC3A
Default condition
Relative cost$$ Standard$$ Standard$$ Standard$$ Standard
Min. machined wall
Best machined surface

Both take the same 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.

Ready to make it?

Upload a CAD file and FabDigit prices the part in AC7A and AC2A 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.