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Zinc Alloy Zn99.99-H vs Zn99.99-HR

Zinc Alloy · Zn99.99 temper comparison

Zn99.99-H and Zn99.99-HR are two conditions of the same zinc alloy grade, Zn99.99: H (hardened) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. Zn99.99-H is the stronger of the two: yield strength 125 MPa (18.1 ksi) against 45 MPa (6.53 ksi) for Zn99.99-HR, about 178% more; tensile strength follows at 190 MPa (27.6 ksi) vs 130 MPa (18.9 ksi). In exchange, Zn99.99-HR is the more ductile: elongation 50% versus 12% for Zn99.99-H, and Zn99.99-H is harder (50 HB vs 35 HB). Zn99.99-HR runs hotter in service (100°C vs 80°C continuous).

Zn99.99-HChoose it when strength drives the design.

Zn99.99-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Zn99.99-H vs Zn99.99-HR: properties

Zn99.99-HZn99.99-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

190 MPa27.6 ksi
130 MPa18.9 ksi

Yield Strength (0.2% offset)

125 MPa18.1 ksi
45 MPa6.5 ksi

Elongation at Break

12%
50%

Shear Strength

110 MPa16 ksi
88 MPa12.8 ksi

Fatigue Strength (Endurance Limit)

42 MPa6.1 ksi
30 MPa4.4 ksi

Hardness, Brinell

50 HB
35 HB

Hardness, Vickers

52 HV
37 HV

Same in both: Elastic (Young's) Modulus 96 GPa13.9 Msi · Shear Modulus 39 GPa5.7 Msi · Bulk Modulus 70 GPa10.2 Msi · Poisson's Ratio 0.25

Physical

Density and transition temperatures.

Same in both: Density 7.14 g/cm³0.26 lb/in³ · Melting Point (Solidus) 420°C787 °F · Liquidus Temperature 420°C787 °F

Thermal

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

Thermal Conductivity

114 W/m·K65.9 BTU/hr·ft·°F
116 W/m·K67 BTU/hr·ft·°F

Max Service Temperature (continuous)

80°C176 °F
100°C212 °F

Same in both: Specific Heat Capacity 390 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 30 µm/m·K16.7 µin/in·°F · Latent Heat of Fusion 112 J/g48.2 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

28 % IACS
28.3 % IACS

Electrical Resistivity

6×10⁻⁸ Ω·m2.36 µΩ·in
5.9×10⁻⁸ Ω·m2.32 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -1.03 V · Corrosion Resistance 40 / 100

Manufacturability

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

Machinability

70 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

70%
62%

Weldability

25 / 100
30 / 100

Formability (cold)

40 / 100
85 / 100

Same in both: Castability 70 / 100 · Brazeability / Solderability 85 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 3.5 kg CO₂/kg · Embodied Water 130 L/kg15.6 gal/lb · Typical Recycled Content 15%

Strength versus weight

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

205010020055.566.57Density (g/cm³)Yield strength (MPa) — log scaleZn99.99

Zn99.99-H vs Zn99.99-HR — frequently asked

Is Zn99.99-H stronger than Zn99.99-HR?

Yes. Zn99.99-H has a typical yield strength of 125 MPa (18.1 ksi) against 45 MPa (6.53 ksi) for Zn99.99-HR — about 178% more. Tensile strength is 190 MPa (27.6 ksi) vs 130 MPa (18.9 ksi).

Which condition does FabDigit quote by default, H or HR?

CR is the default Zn99.99 condition in the FabDigit quote flow (neither H nor HR). 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, Zn99.99-H or Zn99.99-HR?

Zn99.99-H. Its machinability rates very good (70/100) against good (62/100) for Zn99.99-HR; for welding the order is Zn99.99-HR first (poor, 30/100) then Zn99.99-H (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Zn99.99-H and Zn99.99-HR 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.