This specification covers the property requirements and corresponding test methods for two iron-nickel-cobalt alloys in the forms of wire, rod, bar, strip, sheet, and tubing, intended primarily for brazed metal-to-ceramic seals with alumina ceramics, for vacuum electronic applications. The two alloys covered here are UNS K94630 that contains nominally 29 % nickel, 17 % cobalt, and 53 % iron, and UNS K94620 that contains nominally 27 % nickel, 25 % cobalt and 48 % iron. When tested, the alloys shall comply to specified requirements for chemical composition, surface finish, temper, grain size, tensile strength, hardness, inclusion content, thermal expansion, transformation, and dimensions.

1.1 This specification covers two iron-nickel-cobalt alloys, the former, (UNS No. K94630), containing nominally 29 % nickel, 17 % cobalt, and 53 % iron, the latter, (UNS No. K94620), nominally 27 % nickel, 25 % cobalt and 48 % iron, in the forms of wire, rod, bar, strip, sheet, and tubing, intended primarily for brazed metal-to-ceramic seals with alumina ceramics, for vacuum electronic applications. Unless otherwise indicated, all articles apply to both alloys.

1.2 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard.

1.3 The following hazard caveat pertains only to the test method portion, Sections 14 and 16 of this specification. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.