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Aluminum Hokotol-STD vs Hokotol-T651

Aluminum · Hokotol temper comparison

Hokotol-STD and Hokotol-T651 are two conditions of the same aluminum grade, Hokotol: STD (as-supplied high-strength plate) versus T651 (T6, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. Both yield at about 480 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (as-supplied high-strength plate versus T6, stress relieved by stretching). Hokotol-STD is the more ductile: elongation 6% versus 5% for Hokotol-T651. Hokotol-STD runs hotter in service (120°C vs 100°C continuous) and Hokotol-STD conducts heat better (150 W/m·K vs 130 W/m·K).

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

Hokotol-STD vs Hokotol-T651: properties

Hokotol-STDHokotol-T651

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

540 MPa78.3 ksi
565 MPa81.9 ksi

Yield Strength (0.2% offset)

480 MPa69.6 ksi
505 MPa73.2 ksi

Elongation at Break

6%
5%

Fatigue Strength (Endurance Limit)

155 MPa22.5 ksi
160 MPa23.2 ksi

Fracture Toughness (K_IC)

32 MPa·√m29.1 ksi·√in
27 MPa·√m24.6 ksi·√in

Hardness, Brinell

165 HB
172 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 · Compressive Strength 490 MPa71.1 ksi · Shear Strength 320 MPa46.4 ksi

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

150 W/m·K86.7 BTU/hr·ft·°F
130 W/m·K75.1 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
100°C212 °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

39 % IACS
33 % IACS

Same in both: Electrical Resistivity 4.4×10⁻⁸ Ω·m1.73 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

42 / 100
34 / 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

82 / 100
84 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 90% · Weldability 18 / 100 · Formability (cold) 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-STD vs Hokotol-T651 — frequently asked

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

Hokotol-STD and Hokotol-T651 are two conditions of the same aluminum grade, Hokotol: STD (as-supplied high-strength plate) versus T651 (T6, stress relieved by stretching). The chemistry is identical, so every difference below comes from the condition. Both yield at about 480 MPa — the mechanical properties are the same, and the difference is in how the stock is processed and what it is certified to (as-supplied high-strength plate versus T6, stress relieved by stretching).

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

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-STD over Hokotol-T651?

Pick Hokotol-STD 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-STD and Hokotol-T651 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.