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Aluminum 4045-H16 vs 4045-H18

Aluminum · 4045 temper comparison

4045-H16 and 4045-H18 are two conditions of the same aluminum grade, 4045: H16 (strain hardened, three-quarter hard) versus H18 (strain hardened, full hard). The chemistry is identical, so every difference below comes from the condition. 4045-H18 is the stronger of the two: yield strength 195 MPa (28.3 ksi) against 170 MPa (24.7 ksi) for 4045-H16, about 15% more; tensile strength follows at 215 MPa (31.2 ksi) vs 190 MPa (27.6 ksi). In exchange, 4045-H16 is the more ductile: elongation 3% versus 2% for 4045-H18, and 4045-H18 is harder (58 HB vs 52 HB). 4045-H16 runs hotter in service (120°C vs 110°C continuous).

4045-H16Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

4045-H18Choose it when strength drives the design.

4045-H16 vs 4045-H18: properties

4045-H164045-H18

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

190 MPa27.6 ksi
215 MPa31.2 ksi

Yield Strength (0.2% offset)

170 MPa24.7 ksi
195 MPa28.3 ksi

Elongation at Break

3%
2%

Shear Strength

110 MPa16 ksi
125 MPa18.1 ksi

Fatigue Strength (Endurance Limit)

65 MPa9.4 ksi
70 MPa10.2 ksi

Hardness, Brinell

52 HB
58 HB

Same in both: Elastic (Young's) Modulus 71 GPa10.3 Msi · Shear Modulus 26.5 GPa3.8 Msi · Bulk Modulus 72 GPa10.4 Msi · Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Same in both: Density 2.67 g/cm³0.1 lb/in³ · Melting Point (Solidus) 577°C1,071 °F · Liquidus Temperature 591°C1,096 °F

Thermal

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

Thermal Conductivity

163 W/m·K94.2 BTU/hr·ft·°F
162 W/m·K93.6 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
110°C230 °F

Same in both: Specific Heat Capacity 900 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 21 µm/m·K11.7 µin/in·°F · Latent Heat of Fusion 490 J/g211 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 40 % IACS · Electrical Resistivity 4.3×10⁻⁸ Ω·m1.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V · Corrosion Resistance 47 / 100

Manufacturability

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

Machinability

43 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
38%

Weldability

68 / 100
66 / 100

Formability (cold)

38 / 100
28 / 100

Same in both: Castability 88 / 100 · Brazeability / Solderability 98 / 100 · Polishability 40 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12 kg CO₂/kg · Embodied Water 1,100 L/kg132 gal/lb · Typical Recycled Content 35%

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 scale4045

4045-H16 vs 4045-H18 — frequently asked

Is 4045-H18 stronger than 4045-H16?

Yes. 4045-H18 has a typical yield strength of 195 MPa (28.3 ksi) against 170 MPa (24.7 ksi) for 4045-H16 — about 15% more. Tensile strength is 215 MPa (31.2 ksi) vs 190 MPa (27.6 ksi).

Which condition does FabDigit quote by default, H16 or H18?

Specify the condition in the material field or the drawing note; FabDigit prices the quote for the state you call out.

When should I choose 4045-H16 over 4045-H18?

Pick 4045-H16 when the part is bent, formed or impact-loaded, or when the part sees heat. Pick 4045-H18 when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 4045-H16 and 4045-H18 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.