|   | Shanghai Hite Special Alloy Co., Ltd. QUALITY AND SERVICE ARE THE THINGS MAKE US PROUD OF WHAT WE DO | Beijing Time, China | 
Brief introduction:
4J29's Ni-Fe-Co controlled-expansion alloy with Ni29% nominal value.
Its coefficient of expansion matches the expansion rate of borosilicate glasses and alumina ceramics.
It's used for glass-to-metal seals applications, for example:high-power transmitting valves, transistor leads and headers, integrated-circult lead frames and photography flash bulbs.
Main specifications:
| Chinese grade | UNS | ASTM | DIN | Werkstoff Nr. | Germany | Russia | UK | 
| 4J29 | K94610(FeNi29Co17) | F15 | 17745 | 1.3981 | Silvar 48 | 29HK | Nilo K | 
Chemical composition under YB/T5231-2005 standard:
| Grade | chemical composition,% | ||||||||||
| C | P | S | Mn | Si | Cu | Cr | Mo | Ni | Co | Fe | |
| MAX | |||||||||||
| 4J29 | 0.03 | 0.02 | 0.02 | 0.5 | 0.3 | 0.2 | 0.2 | 0.2 | 28.5~29.5 | 16.8~17.8 | Remainder | 
Remarks:If require adjustments for some chemical compositions, pls consult with us.
Tensile strength under YB/T5231-2005 standard:
| delivery condition | Tensile strength of strip ,N/mm2 | Tensile strength of wire,N/mm2 | 
| soft | <570 | <585 | 
| Hard 1/4 | 520-630 | 585-725 | 
| Hard 1/2 | 590-700 | 655-795 | 
| Hard 3/4 | 600-770 | 725-860 | 
| Hard | >700 | >860 | 
Typical average linear expansion coefficient value α,10-6/℃:
| Grade | 20℃~100℃ | 20℃~200℃ | 20℃~300℃ | 20℃~400℃ | 20℃~450℃ | 20℃~500℃ | 20℃~600℃ | 20℃~700℃ | 20℃~800℃ | 
| 4J29 | - | 5.9 | 5.3 | 5.1 | 5.3 | 6.2 | 7.8 | 9.2 | 10.2 | 
Main product types:
wire,rod, bar,strip, plate/sheet,tube,capillary tube, ring,forging.
|  | Kovar document: | 
| kovar.pdf |