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Aluminum 3B21-H19 vs 3B21-H34

Aluminum · 3B21 temper comparison

3B21-H19 and 3B21-H34 are two conditions of the same aluminum grade, 3B21: H19 (strain hardened, extra hard) versus H34 (strain hardened and stabilized, half hard). The chemistry is identical, so every difference below comes from the condition. 3B21-H19 is the stronger of the two: yield strength 220 MPa (31.9 ksi) against 145 MPa (21 ksi) for 3B21-H34, about 52% more; tensile strength follows at 245 MPa (35.5 ksi) vs 175 MPa (25.4 ksi). In exchange, 3B21-H34 is the more ductile: elongation 10% versus 2% for 3B21-H19, and 3B21-H19 is harder (60 HB vs 44 HB). 3B21-H34 runs hotter in service (150°C vs 120°C continuous).

3B21-H19Choose it when strength drives the design.

3B21-H34Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

3B21-H19 vs 3B21-H34: properties

3B21-H193B21-H34

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

245 MPa35.5 ksi
175 MPa25.4 ksi

Yield Strength (0.2% offset)

220 MPa31.9 ksi
145 MPa21 ksi

Elongation at Break

2%
10%

Shear Strength

135 MPa19.6 ksi
105 MPa15.2 ksi

Fatigue Strength (Endurance Limit)

72 MPa10.4 ksi
62 MPa9 ksi

Hardness, Brinell

60 HB
44 HB

Same in both: Elastic (Young's) Modulus 69 GPa10 Msi · Shear Modulus 26 GPa3.8 Msi · Bulk Modulus 70 GPa10.2 Msi · Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Same in both: Density 2.73 g/cm³0.1 lb/in³ · Melting Point (Solidus) 643°C1,189 °F · Liquidus Temperature 654°C1,209 °F

Thermal

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

Thermal Conductivity

155 W/m·K89.6 BTU/hr·ft·°F
158 W/m·K91.3 BTU/hr·ft·°F

Max Service Temperature (continuous)

120°C248 °F
150°C302 °F

Same in both: Specific Heat Capacity 893 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23.2 µm/m·K12.9 µin/in·°F · Latent Heat of Fusion 393 J/g169 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

39 % IACS
40 % IACS

Electrical Resistivity

4.42×10⁻⁸ Ω·m1.74 µΩ·in
4.31×10⁻⁸ Ω·m1.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

68 / 100
70 / 100

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

40 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

150%
122%

Weldability

80 / 100
87 / 100

Formability (cold)

35 / 100
78 / 100

Same in both: Brazeability / Solderability 70 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 1,200 L/kg144 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 scale3B21

3B21-H19 vs 3B21-H34 — frequently asked

Is 3B21-H19 stronger than 3B21-H34?

Yes. 3B21-H19 has a typical yield strength of 220 MPa (31.9 ksi) against 145 MPa (21 ksi) for 3B21-H34 — about 52% more. Tensile strength is 245 MPa (35.5 ksi) vs 175 MPa (25.4 ksi).

Which condition does FabDigit quote by default, H19 or H34?

H14 is the default 3B21 condition in the FabDigit quote flow (neither H19 nor H34). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, 3B21-H19 or 3B21-H34?

3B21-H19. Its machinability rates fair (40/100) against poor (32/100) for 3B21-H34; for welding the order is 3B21-H34 first (excellent, 87/100) then 3B21-H19 (very good, 80/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 3B21-H19 and 3B21-H34 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.