ZTA CERAMIC BALLS
Aluminium Oxide with about 10% content of Zirconium Oxide balls, they feature better mechanical properties, wear and compression resistance and thermal shocks resistance in comparison to nearly pure Aluminium Oxide balls.
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Applications
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Ball bearings, special pumps and valves mainly when both high corrosion resistance and high heat resistance are required. Medical field applications. They are used even as grinding and machining media.
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Commercial name
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Other name
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Formula
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Chemical composition (%)
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|---|---|---|---|
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Zirconia toughened alumina
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ZTA
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Al2O3 + ZrO2 + Y2O3
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Al2O3 ~ 90 / ZrO2 ~ 10
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Physical / mechanical / thermal / electric / magnetic properties
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Property
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Symbol
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U.o.M.
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Type
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Notes
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Values
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|---|---|---|---|---|---|
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Density
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δ
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[g/cm3]
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Physical
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Room temp.
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4.13
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Young's modulus
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E
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[GPa]
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Mechanical
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-
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380
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Friction coefficient
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µ
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-
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Mechanical
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Room temp.
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0.52
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Specific heat
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c
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[J/kg-K]
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Thermal
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Room temp.
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900
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Coefficient of linear thermal expansion
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α
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[10^-6/ºC]
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Thermal
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(ΔT=0-100°C)
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8.0
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Thermal conductivity
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λ
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[W/(m·K)]
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Thermal
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Room temp.
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20.0
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Volume resistivity
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ρ
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[Ω*m]
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Electric
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-
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> 10^15
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Relative magnetic permeability
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µ
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-
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Magnetic
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Diamagnetic
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<~1
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Technical data
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Property
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Type
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U.o.M.
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Values
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U.o.M.
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Values
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|---|---|---|---|---|---|
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Hardness
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Mechanical
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[HV]
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1650 - 1950
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-
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-
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Ultimate compressive strength
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Mechanical
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[MPa]
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1700 - 2300
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[psix10^3]
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247 - 333
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Service temperature
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Thermal
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[ºC]
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-80 / 1500
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[ºF]
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-112 / 2732
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Range
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Diameters (min/max)
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U.o.M.
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Diameters (min/max)
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U.o.M.
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Precision grades (Internal standard*)
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|---|---|---|---|---|
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0.500 - 50.000
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[mm]
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1/32 - 1.15/16
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["]
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G3-5-6-10-25-40-50-100
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Corrosion Resistance
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Good corrosion resistance in almost all diluted and concentrated solutions (both acid and basic, for example nitric acid, sulphuric acid and caustic soda) except against hydrofluoric acid and phosphoric acid. The chemical compatibility is similar to Aluminum Oxide ceramic. ZTA balls can be used even in contact with halogens and melted metals.
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Notes
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Property
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Description
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|---|---|
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*Precision grades
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Allowed tolerances on the diameter and maximum allowed roundness for the confirmed precision grade are always communicated in the offer.
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Revision n.2