The material. Zinc is a bluish-white metal with a low melting point (420°C). The slang in French for a bar or pub is le zinc; bar counters in France used to be clad in zinc—many still are—to protect them from the ravages of wine and beer. Bar surfaces have complex shapes: a flat top, curved profiles, rounded or profiled edges. These two sentences say much about zinc; it is ductile; it is hygienic; it survives exposure to acids (wine), to alkalis (cleaning fluids), and to misuse (upset customers). These remain among the reasons it is still used today. Another is the "castability" of zinc alloys; their low melting point and fluidity give them a leading place in die casting.
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Composition
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Zn + 3-30% Al, typically, often with
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up to 3% Cu.
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General properties
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Density
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4950
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– 7000
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kg/m3
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Price
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*3.09
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– 3.4
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USD/kg
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Mechanical properties
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Young’s modulus
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68
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– 100
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GPa
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Yield strength (elastic limit)
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80
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– 450
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MPa
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Tensile strength
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135
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– 510
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MPa
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Compressive strength
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80
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– 450
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MPa
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Elongation
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1
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– 30
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%
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Hardness—Vickers
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55
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– 160
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HV
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Fatigue strength at 107 cycles
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*20
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– 160
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MPa
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Fracture toughness
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*10
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– 70
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MPa. m1/2
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Thermal properties
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Melting point
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375
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– 492
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°C
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Maximum service temperature
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*80
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– 110
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°C
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Thermal conductor or insulator?
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Good conductor
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Thermal conductivity
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100
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– 130
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W/m. K
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Specific heat capacity
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405
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– 535
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J/kg. K
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Thermal expansion coefficient
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23
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– 28
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p, strain/°C
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Electrical properties
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Electrical conductor or insulator?
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Good conductor
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Electrical resistivity
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5.4
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– 7.2
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puhm. cm
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Zinc die castings are cheap, have high surface finish, and can be complex in shape. On the left, a corkscrew; everything except the screw itself is die-cast zinc alloy. On the right, a carburetor body.
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Ecoproperties: material
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Annual world production
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9.7 x 106
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– 1.0 x 107
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tonne/yr
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Reserves
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2.18 x 108
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– 2.21 x 108
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tonne
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Embodied energy, primary production
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70
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– 75
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MJ/kg
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CO2 footprint, primary production
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3.7
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– 4
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kg/kg
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Water usage
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*160
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– 521
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l/kg
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Eco-indicator
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3000
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– 3400
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millipoints/kg
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Ecoproperties: processing
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Casting energy
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*1.09
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– 1.32
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MJ/kg
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Casting CO2
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*0.065
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– 0.08
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kg/kg
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Recycling
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Embodied energy, recycling
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12.6
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– 13.5
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MJ/kg
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CO2 footprint, recycling
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0.66
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– 0.72
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kg/kg
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Recycle fraction in current supply
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20
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– 25
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%
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Typical uses. Die castings; automotive parts and tools; gears; household goods; office equipment; building hardware; padlocks; toys; business machines; sound reproduction equipment; hydraulic valves; pneumatic valves; soldering; handles; gears; automotive components.
