Kovar

 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:: 

CNiFeSiMnSCoMax0.02Nom29.0BalanceMax0.20Max0.30Max0.025Nom17.0

Thermal Expansion Properties: 

TemperatureCoefficient77°Fto25°Cto10(-6)/°F10(-6)/°C212
392
572
662
752
842
932
1112
1292
1472
1652100
200
300
350
400
450
500
600
700
800
9003.25
2.89
2.85
2.72
2.81
2.92
3.41
4.34
5.06
5.73
6.255.86
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: 

Yield Strength (0.1% Offset)Tensile StrengthElongationpsiMPapsiMPa(%)49,00034075,00052042

Physical Properties: 

DENSITY8.16 g/cm30.295 lb/in3MELTING POINT1450oC2640oFINFLECTION POINT450°C840°FTHERMAL CONDUCTIVITY16.7 W/m•°C116 btu•in/ft2•h°F