... ,UNS K94610 (FeNi29Co17),Chinese 4J29. Note:Sealing alloy Kovar and expansion alloys,Kovar alloy,ASTM F15, Nilo-K,UNS K94610 ( ... FeNi29Co17),Chinese 4J29 A Nickel-Iron-Cobalt, controlled expansion alloy containing 29% Nickel. Its coefficient of expansion (which ... , transistor leads and heaters and photography flash bulbs. Alloy grades and chemical composition consistent with the provisions of ...