Kovar alloy is a vacuum melted, iron-nickel-cobalt alloy that is widely used in the electronics industry.suitable for sealing to hard glasses, in applications requiring high reliability or resistance to thermal shock, ie. high power transmitting valves.
Chemical Compositions::
Chemical Compositions::
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C
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Ni
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Fe
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Si
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Mn
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S
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Co
|
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Max0.02
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Nom29.0
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Balance
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Max0.20
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Max0.30
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Max0.025
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Nom17.0
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Thermal Expansion Properties:
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Temperature
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Coefficient
|
||
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77°F to
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25°C to
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10(-6)/°F
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10(-6)/°C
|
|
212
392 572 662 752 842 932 1112 1292 1472 1652 |
100
200 300 350 400 450 500 600 700 800 900 |
3.25
2.89 2.85 2.72 2.81 2.92 3.41 4.34 5.06 5.73 6.25 |
5.86
5.20 5.13 4.89 5.06 5.25 6.15 7.80 9.12 10.31 11.26 |
Mechanical Properties in the Annealed Condition:
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Yield Strength (0.1% Offset)
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Tensile Strength
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Elongation
|
||
|
psi
|
MPa
|
psi
|
MPa
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(%)
|
|
49,000
|
340
|
75,000
|
520
|
42
|
Physical Properties:
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DENSITY
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8.16 g/cm3
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0.295 lb/in3
|
|
MELTING POINT
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1450oC
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2640oF
|
|
INFLECTION POINT
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450°C
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840°F
|
|
THERMAL CONDUCTIVITY
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16.7 W/m•°C
|
116 btu•in/ft2•h°F
|