Aluminum AC4A vs AC4B
Aluminum · grade comparison
Aluminum AC4A and AC4B are both aluminum grades. AC4A is the stronger of the two: yield strength 200 MPa (29 ksi) against 110 MPa (16 ksi) for AC4B, about 82% more; tensile strength follows at 260 MPa (37.7 ksi) vs 180 MPa (26.1 ksi). AC4A is the more ductile: elongation 3% versus 2% for AC4B, and AC4A is harder (90 HB vs 75 HB). AC4A is lighter (2.68 g/cm³ vs 2.79 g/cm³ for AC4B) and AC4A conducts heat better (150 W/m·K vs 109 W/m·K). On the shop floor, AC4B machines more easily (good vs fair) and AC4A welds better (good vs fair).
AC4AChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
AC4BChoose it when the part is machined in volume.
AC4A vs AC4B: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Same in both: Poisson's Ratio 0.33 · Fracture Toughness (K_IC) 18 MPa·√m16.4 ksi·√in
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Latent Heat of Fusion
Min Service Temperature
Same in both: Specific Heat Capacity 963 J/kg·K0.23 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 21.5 µm/m·K11.9 µin/in·°F · Max Service Temperature (continuous) 150°C302 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Polishability
Same in both: Brazeability / Solderability 25 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.5 MN·m/kg
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.
Manufacturing and finishing
| Capability | AC4A | AC4B |
|---|---|---|
| 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.
AC4A vs AC4B — frequently asked
Is AC4A stronger than AC4B?
Yes. AC4A has a typical yield strength of 200 MPa (29 ksi) against 110 MPa (16 ksi) for AC4B — about 82% more. Tensile strength is 260 MPa (37.7 ksi) vs 180 MPa (26.1 ksi).
Which is cheaper, AC4A or AC4B?
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, AC4A or AC4B?
AC4B. Its machinability rates good (68/100) against fair (50/100) for AC4A; for welding the order is AC4A first (good, 65/100) then AC4B (fair, 45/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in AC4A and AC4B 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.