Aluminum 4045 vs 4643
Aluminum · grade comparison
Aluminum 4045 and 4643 are both aluminum grades, both heat resistant al. 4643 is the stronger of the two: yield strength 70 MPa (10.2 ksi) against 45 MPa (6.53 ksi) for 4045, about 56% more; tensile strength follows at 165 MPa (23.9 ksi) vs 110 MPa (16 ksi). In exchange, 4045 is the more ductile: elongation 20% versus 15% for 4643, and 4643 is harder (45 HB vs 30 HB). On the shop floor, 4643 welds better (excellent vs very good).
4045Choose it when the part is bent, formed or impact-loaded.
4643Choose it when strength drives the design, or when it will be welded.
4045 vs 4643: 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
Shear Strength
Hardness, Brinell
Same in both: Poisson's Ratio 0.33 · Fatigue Strength (Endurance Limit) 50 MPa7.3 ksi
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
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Same in both: Max Service Temperature (continuous) 150°C302 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
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)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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 | 4045 | 4643 |
|---|---|---|
| CNC machining | — | Yes |
| Default condition | — | — |
| Relative cost | $$ Standard | $$ Standard |
| Min. machined wall | — | 0.5 mm |
| Best machined surface | — | Ra 0.8 µm |
| DLC | — | Yes |
Both are offered for Sheet metal. They share 15 finishes: Anodizing Type II, Cerakote, Chem Film (Alodine), E-Coating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Nickel Plating, PTFE Coating and 3 more.
4045 vs 4643 — frequently asked
Is 4643 stronger than 4045?
Yes. 4643 has a typical yield strength of 70 MPa (10.2 ksi) against 45 MPa (6.53 ksi) for 4045 — about 56% more. Tensile strength is 165 MPa (23.9 ksi) vs 110 MPa (16 ksi).
Which is cheaper, 4045 or 4643?
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 welds better, 4045 or 4643?
4643. Its weldability rates excellent (96/100) against very good (70/100) for 4045.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4045 and 4643 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.