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Zinc Alloy Zn99.5-H vs Zn99.5-HR

Zinc Alloy · Zn99.5 temper comparison

Zn99.5-H and Zn99.5-HR are two conditions of the same zinc alloy grade, Zn99.5: H (hardened) versus HR (hot rolled). The chemistry is identical, so every difference below comes from the condition. Zn99.5-H is the stronger of the two: yield strength 140 MPa (20.3 ksi) against 80 MPa (11.6 ksi) for Zn99.5-HR, about 75% more; tensile strength follows at 180 MPa (26.1 ksi) vs 130 MPa (18.9 ksi). In exchange, Zn99.5-HR is the more ductile: elongation 45% versus 25% for Zn99.5-H, and Zn99.5-H is harder (47 HB vs 35 HB). Zn99.5-HR runs hotter in service (100°C vs 80°C continuous).

Zn99.5-HChoose it when strength drives the design.

Zn99.5-HRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Zn99.5-H vs Zn99.5-HR: properties

Zn99.5-HZn99.5-HR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

180 MPa26.1 ksi
130 MPa18.9 ksi

Yield Strength (0.2% offset)

140 MPa20.3 ksi
80 MPa11.6 ksi

Elongation at Break

25%
45%

Shear Strength

130 MPa18.9 ksi
100 MPa14.5 ksi

Fatigue Strength (Endurance Limit)

45 MPa6.5 ksi
32 MPa4.6 ksi

Hardness, Brinell

47 HB
35 HB

Hardness, Vickers

50 HV
37 HV

Same in both: Elastic (Young's) Modulus 95 GPa13.8 Msi · Shear Modulus 38 GPa5.5 Msi · Bulk Modulus 70 GPa10.2 Msi · Poisson's Ratio 0.25 · Charpy V-Notch Impact (RT) 6 J4.4 ft·lbf

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

112 W/m·K64.7 BTU/hr·ft·°F
113 W/m·K65.3 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 -30°C-22 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

27 % IACS
28 % IACS

Electrical Resistivity

6.1×10⁻⁸ Ω·m2.4 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 55 / 100

Manufacturability

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

Machinability

80 / 100
72 / 100

Machinability Rating (AISI 1212 = 100 %)

75%
68%

Weldability

35 / 100
42 / 100

Formability (cold)

65 / 100
80 / 100

Same in both: Castability 85 / 100 · Brazeability / Solderability 92 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb · Embodied Carbon (primary production) 3.6 kg CO₂/kg · Embodied Water 120 L/kg14.4 gal/lb · Typical Recycled Content 30%

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 scaleZn99.5

Zn99.5-H vs Zn99.5-HR — frequently asked

Is Zn99.5-H stronger than Zn99.5-HR?

Yes. Zn99.5-H has a typical yield strength of 140 MPa (20.3 ksi) against 80 MPa (11.6 ksi) for Zn99.5-HR — about 75% more. Tensile strength is 180 MPa (26.1 ksi) vs 130 MPa (18.9 ksi).

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

R is the default Zn99.5 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, Zn99.5-H or Zn99.5-HR?

Zn99.5-H, by a small margin. Both rate very good for machinability — 80/100 against 72/100 for Zn99.5-HR; for welding the order is Zn99.5-HR first (fair, 42/100) then Zn99.5-H (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Zn99.5-H and Zn99.5-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.