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.

This abstract is a brief summary of the referenced standard. It is informational only and not an official part of the standard; the full text of the standard itself must be referred to for its use and application. ASTM does not give any warranty express or implied or make any representation that the contents of this abstract are accurate, complete or up to date.

1. Scope

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.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1971 Practices for Digestion of Water Samples for Determination of Metals by Flame Atomic Absorption, Graphite Furnace Atomic Absorption, Plasma Emission Spectroscopy, or Plasma Mass Spectrometry

E3 Guide for Preparation of Metallographic Specimens

E8 Test Methods for Tension Testing of Metallic Materials

E18 Test Methods for Rockwell Hardness of Metallic Materials

E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

E45 Test Methods for Determining the Inclusion Content of Steel

E92 Test Method for Vickers Hardness of Metallic Materials

E112 Test Methods for Determining Average Grain Size

E140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness, Superficial Hardness, Knoop Hardness, and Scleroscope Hardness

E228 Test Method for Linear Thermal Expansion of Solid Materials With a Push-Rod Dilatometer

E354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron, Nickel, and Cobalt Alloys

E1019 Test Methods for Determination of Carbon, Sulfur, Nitrogen, and Oxygen in Steel, Iron, Nickel, and Cobalt Alloys by Various Combustion and Fusion Techniques

E1060

Keywords

control of thermal expansion; iron-nickel-cobalt alloys; metal/ceramic brazing; oxide-forming impurities and inclusions; UNS No. K94620; UNS No. K94630; vacuum electronic applications; Control (thermal expansion); Electronic materials/applications--specifications; Electronic materials/applications (ceramics)--specifications; Glass electronic seals; Iron-nickel-cobalt alloys--specifications; Metal/ceramic brazing; Oxide-forming impurities/inclusions; Seals--electronic applications (specifications); Thermal expansion/contraction; UNS K94620 (Fe-Ni-Co, metal-to-ceramic sealing alloy); UNS K94630 (Fe-Ni-Co, metal-to-ceramic sealing alloy); Vacuum electronic applications;

ICS Code

ICS Number Code 21.140 (Seals, glands); 77.080.10 (Irons)

Citing ASTM Standards

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