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Magnesium Alloy ZK51A-F vs ZK51A-T5

Magnesium Alloy · ZK51A temper comparison

ZK51A-F and ZK51A-T5 are two conditions of the same magnesium alloy grade, ZK51A: F (as fabricated) versus T5 (cooled from hot working and artificially aged). The chemistry is identical, so every difference below comes from the condition. ZK51A-T5 is the stronger of the two: yield strength 165 MPa (23.9 ksi) against 125 MPa (18.1 ksi) for ZK51A-F, about 32% more; tensile strength follows at 205 MPa (29.7 ksi) vs 175 MPa (25.4 ksi). In exchange, ZK51A-F is the more ductile: elongation 5% versus 3.5% for ZK51A-T5, and ZK51A-T5 is harder (65 HB vs 55 HB). ZK51A-T5 runs hotter in service (120°C vs 110°C continuous).

ZK51A-FChoose it when the part is bent, formed or impact-loaded.

ZK51A-T5Choose it when strength drives the design, or when the part sees heat.

ZK51A-F vs ZK51A-T5: properties

ZK51A-FZK51A-T5

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

175 MPa25.4 ksi
205 MPa29.7 ksi

Yield Strength (0.2% offset)

125 MPa18.1 ksi
165 MPa23.9 ksi

Elongation at Break

5%
3.5%

Compressive Strength

150 MPa21.8 ksi
170 MPa24.7 ksi

Shear Strength

145 MPa21 ksi
160 MPa23.2 ksi

Fatigue Strength (Endurance Limit)

60 MPa8.7 ksi
70 MPa10.2 ksi

Fracture Toughness (K_IC)

15 MPa·√m13.7 ksi·√in
14 MPa·√m12.7 ksi·√in

Charpy V-Notch Impact (RT)

3 J2.2 ft·lbf
3 J1.8 ft·lbf

Hardness, Brinell

55 HB
65 HB

Same in both: Elastic (Young's) Modulus 45 GPa6.5 Msi · Shear Modulus 16.5 GPa2.4 Msi · Bulk Modulus 45 GPa6.5 Msi · Poisson's Ratio 0.35

Physical

Density and transition temperatures.

Same in both: Density 1.81 g/cm³0.07 lb/in³ · Melting Point (Solidus) 549°C1,020 °F · Liquidus Temperature 640°C1,184 °F

Thermal

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

Thermal Conductivity

105 W/m·K60.7 BTU/hr·ft·°F
109 W/m·K63 BTU/hr·ft·°F

Max Service Temperature (continuous)

110°C230 °F
120°C248 °F

Same in both: Specific Heat Capacity 1,000 J/kg·K0.24 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 27 µm/m·K15 µin/in·°F · Latent Heat of Fusion 340 J/g146 BTU/lb · Min Service Temperature -100°C-148 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

26 % IACS
27 % IACS

Electrical Resistivity

6.6×10⁻⁸ Ω·m2.6 µΩ·in
6.4×10⁻⁸ Ω·m2.52 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -1.58 V · Corrosion Resistance 22 / 100

Manufacturability

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

Same in both: Machinability 98 / 100 · Machinability Rating (AISI 1212 = 100 %) 500% · Weldability 15 / 100 · Formability (cold) 10 / 100 · Castability 60 / 100 · Brazeability / Solderability 15 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 320 MJ/kg137,575 BTU/lb · Embodied Carbon (primary production) 32 kg CO₂/kg · Embodied Water 500 L/kg59.9 gal/lb · Typical Recycled Content 20%

Strength versus weight

Yield strength against density for every magnesium alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

701001502001.41.51.61.71.8Density (g/cm³)Yield strength (MPa) — log scaleZK51A

ZK51A-F vs ZK51A-T5 — frequently asked

Is ZK51A-T5 stronger than ZK51A-F?

Yes. ZK51A-T5 has a typical yield strength of 165 MPa (23.9 ksi) against 125 MPa (18.1 ksi) for ZK51A-F — about 32% more. Tensile strength is 205 MPa (29.7 ksi) vs 175 MPa (25.4 ksi).

Which condition does FabDigit quote by default, F or T5?

T5 is the default ZK51A condition in the FabDigit quote flow. 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.

When should I choose ZK51A-F over ZK51A-T5?

Pick ZK51A-F when the part is bent, formed or impact-loaded. Pick ZK51A-T5 when strength drives the design, or when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in ZK51A-F and ZK51A-T5 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.