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Aluminum Hokotol-T651 vs Hokotol-T7651

Aluminum · Hokotol temper comparison

Hokotol-T651 and Hokotol-T7651 are two conditions of the same aluminum grade, Hokotol: T651 (T6, stress relieved by stretching) versus T7651 (T76, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. Both yield at about 505 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (T6, stress relieved by stretching versus T76, stress relieved by stretching). Hokotol-T7651 is the more ductile: elongation 6% versus 5% for Hokotol-T651, and Hokotol-T651 is harder (172 HB vs 162 HB). Hokotol-T7651 runs hotter in service (120°C vs 100°C continuous) and Hokotol-T7651 conducts heat better (148 W/m·K vs 130 W/m·K).

Hokotol-T7651Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Hokotol-T651 vs Hokotol-T7651: properties

Hokotol-T651Hokotol-T7651

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

565 MPa81.9 ksi
545 MPa79 ksi

Yield Strength (0.2% offset)

505 MPa73.2 ksi
485 MPa70.3 ksi

Elongation at Break

5%
6%

Compressive Strength

490 MPa71.1 ksi
495 MPa71.8 ksi

Shear Strength

320 MPa46.4 ksi
322 MPa46.7 ksi

Fatigue Strength (Endurance Limit)

160 MPa23.2 ksi
155 MPa22.5 ksi

Fracture Toughness (K_IC)

27 MPa·√m24.6 ksi·√in
31 MPa·√m28.2 ksi·√in

Hardness, Brinell

172 HB
162 HB

Same in both: Elastic (Young's) Modulus 71 GPa10.3 Msi · Shear Modulus 26.9 GPa3.9 Msi · Bulk Modulus 74 GPa10.7 Msi · Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Same in both: Density 2.82 g/cm³0.1 lb/in³ · Melting Point (Solidus) 477°C891 °F · Liquidus Temperature 635°C1,175 °F

Thermal

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

Thermal Conductivity

130 W/m·K75.1 BTU/hr·ft·°F
148 W/m·K85.5 BTU/hr·ft·°F

Max Service Temperature (continuous)

100°C212 °F
120°C248 °F

Same in both: Specific Heat Capacity 860 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23.4 µm/m·K13 µin/in·°F · Latent Heat of Fusion 390 J/g168 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

33 % IACS
38 % IACS

Electrical Resistivity

4.4×10⁻⁸ Ω·m1.73 µΩ·in
4.54×10⁻⁸ Ω·m1.79 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

34 / 100
43 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.84 V

Manufacturability

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

Machinability

84 / 100
82 / 100

Formability (cold)

18 / 100
20 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 90% · Weldability 18 / 100 · Brazeability / Solderability 10 / 100 · Polishability 75 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 155 MJ/kg66,638 BTU/lb · Embodied Carbon (primary production) 12 kg CO₂/kg · Embodied Water 1,200 L/kg144 gal/lb · Typical Recycled Content 25%

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 scaleHokotol

Hokotol-T651 vs Hokotol-T7651 — frequently asked

What is the difference between Hokotol-T651 and Hokotol-T7651?

Hokotol-T651 and Hokotol-T7651 are two conditions of the same aluminum grade, Hokotol: T651 (T6, stress relieved by stretching) versus T7651 (T76, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. Both yield at about 505 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (T6, stress relieved by stretching versus T76, stress relieved by stretching).

Which condition does FabDigit quote by default, T651 or T7651?

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 Hokotol-T651 over Hokotol-T7651?

Pick Hokotol-T7651 when the part is bent, formed or impact-loaded, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Hokotol-T651 and Hokotol-T7651 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.