Kovar foil (Alloy K) is used for high-power transmitting valves, transistor leads and headers, integrated-circuit lead frames, and photography flash bulbs. UNS K94610 Werkstoff Nr 1.3981 DIN 17745 ASTM F 15 AMS 7726 Wire AMS 7727 Bars and Forgings AMS 7728 Sheet, Strip and Plate MIL-I-23011 class 1 AFNOR NF A54-301 S.E.W 385 DILVER P
Kovar foil (Alloy K) is used for high-power transmitting valves, transistor leads and headers, integrated-circuit lead frames, and photography flash bulbs.
SPECIFICATION
ASTM F15
UNS K94610
Werkstoff Nr 1.3981
DIN 17745
MIL-I23011 Class 1
AFNOR NF A54-301
S.E.W 385
PRODUCT DATASHEET
Table 1 Chemistry Composition (Weight Percent)
| Element | C≤ | P≤ | S≤ | Mn≤ | Si≤ | Cr≤ | Cu≤ | Mo≤ | Ni | Co | Fe |
| Composition% | 0.03 | 0.020 | 0.020 | 0.5 | 0.3 | 0.20 | 0.20 | 0.20 | 28.5-29.5 | 16.8-17.8 | Remainder |
Notes:
1.The shape and dimensions of the alloys are in compliance with ASTM F15
2.We offer kovar strip coil in custom Tempers from Annealed to Full Hard
Table 2 Physical Properties
| Specific Gravity | 8.36 | |
| Density | 0.32 (Ib/cu in) | 8359 (kg/cu m) |
| Curie Temperature | 815 (°F) | 435 (°C) |
| Thermal Conductivity | 120 (Btu-in/ft2/hr/°F) | 17.3 (W/m-K) |
| Melting Point | 2640 (°F) | 1450 (°C) |
| Electrical Resistivity | 294 (ohm-cir mil/ft) | 490 (microhm) |
| Modulus of Elasticity | 20 (Psi x 106 ) | 138 ( MPa x 103) |
Table 3 Machanical Property
| Temper Designation | Temper name | Tensile Strength/MPa |
| A | Annealed | <585 |
| B | 1/4 Hard | 585-725 |
| C | 1/2 Hard | 655-795 |
| D | 3/4 Hard | 725-865 |
| E | Hard | >860 |
Table 4 Tensile Strength Strip
| Temper Designation | Tamper Name | Tensile Strength/MPa |
| A | Annealed | <570 |
| B | 1/4 Unannealed | 520-700 |
| C | 1/2 Unanealed | 590-700 |
| D | 3/4 Unanealed | 600-770 |
| E | Hard | >700 |
Table 5 Hardness of Deep Stamping Strip
| State | Thickness | Hardness,Hv |
| Deep Stamping | >2.5 | ≤170 |
| ≤2.5 | ≤165 |
Table 6 Coefficient of Linear Expansion
| Heat Treament of The Sample | Average Coefficient of Linear Expansion | ||
| Heat to temperature of 900±20ºC in the hydrogen,hold for 1h;re-heat to 1100±20ºC, hold for 15 min.;cooled to 200ºC at a rate less than 5ºC/min | 20-300°C | 20-400°C | 20-450°C |
| 4.6-5.2 | 5.1-5.5 | ||
Table 7 Thermal Coefficient
| 20-200°C | 20-300°C | 20-400°C | 20-450°C | 20-500°C | 20-600°C | 20-700°C | 20-800°C |
| 5.9 | 5.3 | 5.1 | 5.3 | 6.2 | 7.8 | 9.2 | 10.2 |