Kovar® Properties and Standards – ASTM F15 Alloy

Pernifer® 2918, Dilver® P1, Nilo® K

kovar properties physical mechanical expansion chemistry specificationsEd Fagan Inc. knows how important the properties of Kovar®, ASTM F15 are to you when evaluating an alloy for an application.  As a reference, we have comprised tables with key data points to guide customers in their evaluation of Kovar®, ASTM F15 Alloy.  Tables include physical, expansion and chemistry properties along with specifications.

For further information on Kovar®, ASTM F15 Alloy, do not hesitate to call us at 800-348-6268.  Our professional sales team are experts in the materials we sell and waiting to assist you in finding a solution to your alloy needs. For a Kovar® data sheet, or any other Controlled Expansion Alloy data sheets, please go to our Alloys and Metals Literature Library section.

Remember, no order quantity is too small at Ed Fagan Inc.  We serve all individuals, markets and industries with our high-quality special metals and alloys.

ASTM F15 (Kovar®)
Average Linear Coefficients of Thermal Expansion 
Temp Range, °CTemp Range, °C
30-100--30-4505.1 – 5.5
30-4004.6 – 5.230-90011.5

Bold face values are the limits specified in ASTM F15.


For comparison linear coefficient of thermal expansion data on all of our controlled expansion, glass and ceramic sealing alloys, please refer to our Thermal Expansion Table.

ASTM F15 Alloy (Kovar®)
Physical Properties

Densitylb/cu in0.302
Specific Gravity8.36
Curie Temp°F815
Melting Point°F2640
Electrical ResistivityMicrohms-cm49
ohm-cir mil/ft294
Thermal ConductivityW/cm °C0.17
BTU-in/sq. ft-hr-°F120
Specific HeatCal/gm °C0.11
BTU/lbm- °F0.11
Thermal Expansionppm / °F (75°F to 842°F)2.9
ppm / °C (25°C to 450 °C)5.3
ASTM F15 Alloy (Kovar®) Typical Mechanical Properties  
Tensile Strengthksi75
Yield Strengthksi50
Elongation% in 2"30
Hardness (annealed)Rockwell B68
Modulus of Elasticityksi20,000
Poisson's Ratio0.317
ASTM F15 (Kovar®)
Composition %
Iron, nominal53
Nickel, nominal29
Cobalt, nominal17
Manganese, max0.50
Silicon, max0.20
Carbon, max0.04
Copper, max0.20
Chromium, max0.20
Molybdenum, max0.20
Aluminum, max0.10
Magnesium, max0.10
Zirconium, max0.10
Titanium, max0.10
The iron, nickel and cobalt % listed are nominal. They shall be adjusted by the manufacturer so that the alloy meets the requirements for coefficient of thermal expansion
The total aluminum, magnesium, zirconium and titanium shall not exceed 0.20%
Specifications- Our material is certified to: 
UNS K94610
AMS 1-23011 CL1MIL 1-23011 CL1
Specifications- Historic Cross- Reference 
ASTM F1466UNS K94360AMS 7726B, 7727, 7728C

For additional information on specifications of the materials distributed by Ed Fagan Inc., please visit the websites of the international standards organizations that develops and publishes technical standards, ASTM International and ASM International.

Ed Fagan Inc. supplies the highest quality special purpose metals and alloys.  We stock controlled expansion, refractory, soft magnetic alloys and electronic nickels found in applications for aerospace, aviation, defense, electronics, energy, medical, optical, research and other high-technology industries.