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Aluminum AC2B vs AC8A

Aluminum · grade comparison

Aluminum AC2B and AC8A are both aluminum grades. AC8A is the stronger of the two: yield strength 240 MPa (34.8 ksi) against 110 MPa (16 ksi) for AC2B, about 118% more; tensile strength follows at 285 MPa (41.3 ksi) vs 180 MPa (26.1 ksi). In exchange, AC2B is the more ductile: elongation 2% versus 1% for AC8A, and AC8A is harder (115 HB vs 70 HB). AC8A is stiffer (82 GPa vs 74 GPa) and AC8A runs hotter in service (250°C vs 150°C continuous). On the shop floor, AC2B machines more easily (good vs fair) and AC2B welds better (fair vs poor).

AC2BChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

AC8AChoose it when strength drives the design, or when the part sees heat.

AC2B vs AC8A: properties

AC2BAC8A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

74 GPa10.7 Msi
82 GPa11.9 Msi

Shear Modulus

28 GPa4.1 Msi
27 GPa3.9 Msi

Bulk Modulus

71 GPa10.3 Msi
76 GPa11 Msi

Tensile Strength (Ultimate)

180 MPa26.1 ksi
285 MPa41.3 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
240 MPa34.8 ksi

Elongation at Break

2%
1%

Compressive Strength

115 MPa16.7 ksi
340 MPa49.3 ksi

Shear Strength

145 MPa21 ksi
195 MPa28.3 ksi

Fatigue Strength (Endurance Limit)

70 MPa10.2 ksi
95 MPa13.8 ksi

Fracture Toughness (K_IC)

17 MPa·√m15.5 ksi·√in
16 MPa·√m14.6 ksi·√in

Charpy V-Notch Impact (RT)

4 J3 ft·lbf
3 J1.8 ft·lbf

Hardness, Brinell

70 HB
115 HB

Hardness, Rockwell B

—
65 HRB

Hardness, Vickers

—
120 HV

Same in both: Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Density

2.77 g/cm³0.1 lb/in³
2.7 g/cm³0.1 lb/in³

Melting Point (Solidus)

516°C961 °F
525°C977 °F

Liquidus Temperature

604°C1,119 °F
580°C1,076 °F

Thermal

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

Thermal Conductivity

109 W/m·K63 BTU/hr·ft·°F
130 W/m·K75.1 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

21.5 µm/m·K11.9 µin/in·°F
19.5 µm/m·K10.8 µin/in·°F

Latent Heat of Fusion

389 J/g167 BTU/lb
470 J/g202 BTU/lb

Max Service Temperature (continuous)

150°C302 °F
250°C482 °F

Min Service Temperature

-196°C-321 °F
-50°C-58 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

27 % IACS
28 % IACS

Electrical Resistivity

6.4×10⁻⁸ Ω·m2.52 µΩ·in
6.2×10⁻⁸ Ω·m2.44 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.81 V
-0.78 V

Corrosion Resistance

42 / 100
36 / 100

Manufacturability

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

Machinability

65 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

130%
45%

Weldability

35 / 100
25 / 100

Formability (cold)

5 / 100
4 / 100

Polishability

40 / 100
45 / 100

Same in both: Castability 85 / 100 · Brazeability / Solderability 20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Water

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

Typical Recycled Content

85%
60%

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

65 kN·m/kg
106 kN·m/kg

Specific Stiffness (E / density)

26.7 MN·m/kg
30.4 MN·m/kg

Modulus of Resilience

82 kJ/m³
351 kJ/m³

Thermal Diffusivity

40.9 mm²/s
54.7 mm²/s

Thermal Shock Resistance Index

12
23

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 scaleAC2BAC8A

Manufacturing and finishing

CapabilityAC2BAC8A
Default condition——
Relative cost$$ Standard$$ Standard
Min. machined wall——
Best machined surface——

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

AC2B vs AC8A — frequently asked

Is AC8A stronger than AC2B?

Yes. AC8A has a typical yield strength of 240 MPa (34.8 ksi) against 110 MPa (16 ksi) for AC2B — about 118% more. Tensile strength is 285 MPa (41.3 ksi) vs 180 MPa (26.1 ksi).

Which is cheaper, AC2B or AC8A?

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, AC2B or AC8A?

AC2B. Its machinability rates good (65/100) against fair (50/100) for AC8A; for welding the order is AC2B first (fair, 35/100) then AC8A (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in AC2B and AC8A 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.