1、Designation: F 29 97 (Reapproved 2002)Standard Specification forDumet Wire for Glass-to-Metal Seal Applications1This standard is issued under the fixed designation F 29; the number immediately following the designation indicates the year of originaladoption or, in the case of revision, the year of l
2、ast revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers round, copper-coated 42 %nickel-iron wire, commonly known as dumet, intended prima-rily for
3、sealing to soft glass.1.2 The values stated in inch-pound units are to be regardedas the standard. The metric equivalents of inch-pound unitsmay be approximate.2. Referenced Documents2.1 ASTM Standards:B 170 Specification for Oxygen-Free Electrolytic CopperRefinery Shapes2D 1535 Test Method for Spec
4、ifying Color by the MunsellSystem3D 1729 Practice for Visual Evaluation of Color Differencesof Opaque Materials3E 3 Methods of Preparation of Metallographic Specimens4E 29 Practice for Using Significant Digits in Test Data toDetermine Conformance with Specifications5E 53 Methods for Chemical Analysi
5、s of Copper6E 228 Test Methods for Linear Thermal Expansion of SolidMaterials With a Vitreous Silicon Dilatometer5F 14 Practice for Making and Testing Reference Glass-Metal Bead-Seal73. Ordering Information3.1 The wire is usually supplied with a surface coatingconsisting of a mixture of copper oxide
6、s and fused sodiumtetraborate (borax) which retards oxidation of the wire duringsealing in glass and further aids wetting of the wire by theglass. The composite wire may also be purchased as bare wirefor specific applications.3.2 The size of the wire, if applicable, the borate color rangedesignated
7、as light, medium (regular), or dark, shall bespecified on each purchase order.3.3 Package sizes shall be agreed upon between the pur-chaser and the seller.4. Chemical Composition4.1 The copper used in the manufacture of dumet shall be99.90 % minimum copper. Silver shall be included with thecopper. T
8、he material shall be free of reducible oxides.4.2 The chemical composition of the nickel-iron core shallbe as shown in Table 1.5. Oxide Coating5.1 The primary standards for the entire range of colors aredivided into three groups covering light, medium (regular), anddark as shown, with their respecti
9、ve limits, in Fig. 1 and Table2 (Note 1). The color range of the specimens shall bedetermined in accordance with 9.2.NOTE 1Color chip 2.5R 3.90/8.0 may be included in the dark rangemerely to extend the color series for assisting the viewer in making abetter decision regarding the cut-off point betwe
10、en medium (regular) anddark dumet.6. Thermal Expansion6.1 The nominal values for the average coefficient of linearthermal expansion shall be as follows when determined inaccordance with 9.1:6.1.1 Core63 to 72 3 107in./in.deg C (mm/mmdegC) over the temperature range of 30 to 400C.1This specification
11、is under the jurisdiction of ASTM-Committee F01 onElectronics and is the direct responsibility of Subcommittee F01.03 on MetallicMaterials.Current edition approved Dec. 10, l997. Published March 1998. Originallypublished as F29 63 T. Last previous edition F29 78 (1991).2Annual Book of ASTM Standards
12、, Vol 02.01.3Annual Book of ASTM Standards, Vol 06.01.4Annual Book of ASTM Standards, Vol 03.01.5Annual Book of ASTM Standards, Vol 14.02.6Annual Book of ASTM Standards, Vol 03.05.7Annual Book of ASTM Standards, Vol 15.02.TABLE 1 Chemical Requirements: Core MaterialElement Composition, %Nickel 41 to
13、 43Manganese 0.75 to 1.25Silicon, max 0.30Carbon, max 0.10Sulfur, max 0.02Phosphorus, max 0.02Iron (by difference) remainder1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6.1.2 Copper177 6 3.5 3 107in./in.C (mm/mmdegC) over the temp
14、erature range of 30 to 300C.7. Dimensional Tolerances7.1 The specified diameters shall conform to the tolerancesgiven in Table 3.8. Workmanship and Finish8.1 Internal ConditionThe internal structure of the com-posite material, including the bond area, shall be sound andfree from pipes, porosity, or
15、discontinuities which mightprevent the making of a satisfactory seal.8.2 Surface Condition:8.2.1 There shall be no areas of exposed core evident on thesurface of the wire.8.2.2 The wire shall contain no longitudinal scratches, folds,or lines of a depth greater than the width.8.2.3 There shall be no
16、oil, grease, or other surface contami-nants on the wire.8.2.4 The wire shall be looped or coiled over a mandrel fivetimes the diameter of the wire. At least 75 % of the dumet areashall be free from defects consisting of damaged borate,exposing the copper, when observed at 103 magnification.8.2.5 The
17、 nickel-iron core shall be uniformly covered with18 % to 28 % copper (by weight) and the ratio of maximum tominimum sheath thickness shall not exceed 2.5 to 1 on anycross section.NOTE 2The sheath is defined as that area exclusive of the core.8.3 StorageFinished material should be stored in a con-tai
18、ner or room with a maximum relative humidity of 50 %.9. Test Methods9.1 Thermal ExpansionDetermine the thermal expansioncharacteristics in accordance with Test Method E 228, exceptthat the specimen shall be preheated as follows:9.1.1 Heat the core rod specimen in a hydrogen atmospherefor1hat900C; th
19、en cool it from 900 to 200C at a rate notexceeding 5C/min.9.1.2 Determine the thermal expansion charateristics inaccordance with Test Method E 228.9.2 Color of Coating Mount the color chips8on a neutralbackground (middle gray to white) as shown in Fig. 1. Windthe specimen to be tested or compared on
20、 a flat surface similarto that shown in Fig. 1. Each turn of the wire should lie paralleland as close as possible to the preceding turn without overlap-ping. View the specimen in natural or artificial daylight inaccordance with either or both Method D 1535, (Note 3) orTest Method D 1729Fig. 2.NOTE 3
21、Coated wire carries a mixture of copper oxides and fusedsodium tetraborate on the surface of the dumet, which dissolves, wholly orin part, into the glass during the sealing operation. The sealing techniqueis influenced by the amount of coating, and color has been established asa means of estimating
22、the thickness of this mixture. The color varies froma dark red-purple to a light yellow-red as the thickness decreases. The8The sole source of supply of the color standards known to the committee at thistime is the Munsell Color Company, Inc., 2441 N. Calvert St., Baltimore, MD21218. If you are awar
23、e of alternative suppliers, please provide this information toASTM Headquarters. Your comments will receive careful consideration at a meetingof the responsible technical committee11, which you may atttend.NOTE 1Wire winding shall be in the same plane as shown and the specimen in the same plane as t
24、he color chips. The specimen shall be viewed alongdirection AB at an inclined angle as illustrated.FIG. 1 Arrangement of Color Chips for Specimen ComparisonTABLE 2 Color Ranges and LimitsDark RangeMedium (Regular)RangeLight RangeColors darker than chip 3.5R3.94/8.03.5R 3.94/8.0 to 6.5R4.06/8.0, incl
25、7.5R 4.22/8.0 to 0.5YR4.56/8.0 inclTABLE 3 Dimensional TolerancesDiameter, in. (mm) Tolerance, in.(mm)0.007 to 0.013 (0.18 to 0.33) 60.0003 (60.008)Over 0.013 to 0.018 (0.33 to 0.46) 60.0004 (60.010)Over 0.018 (0.46) 60.0005 (60.013)F 29 97 (2002)2method, described in Test Method D 1535, is based on
26、 the color-perception attributes of hue, lightness, and saturation and is used as themeans for specifying color. This method employs the Munsell color-notation system in which visual scales are assigned to each of thecolor-perception attributes. In this system, the attributes are called hue, H,value
27、, V, and chroma, C, written in the form H V/C. By using acombination of numbers and letters, apparent color may be exactlyspecified. The dimensions of the surface-color-perception solid are illus-trated in Fig. 2.9.3 DiameterThe diameter of the wire in coils shall bemeasured at each end. When wire i
28、s spooled, approximately 6ft (1.8 m) shall be unreeled and the diameter of the wiremeasured between the second and sixth foot from the end. Theaverage of the measurements obtained on any coil or spoolshall be within the limits specified in Section 7.9.4 Reducible Oxides Copper shall be tested for re
29、ducibleoxides in accordance with the methods described in Specifica-tion B 170.9.5 Copper Analysis Copper shall be analyzed by wetchemical methods in accordance with Methods E 53.9.6 Metallographic TestThe internal structure of the wireshall be checked by standard metallographic methods asdescribed
30、in Method E 3.10. Rejection10.1 Any spool or coil not conforming to the requirementsof this specification may be rejected. If 15 % or more of thespools in any shipment do not conform to the specifiedrequirements, the entire shipment may be rejected.11. Packaging and Marking11.1 Unless otherwise spec
31、ified, wire supplied on spools orcoils shall be continuous with no joints of any type.11.2 The wire shall be spooled in such a manner that it canbe unwound under reasonable tension without binding orotherwise becoming distorted.11.3 Each spool or coil shall be marked as to wire size,color, date, net
32、 weight, and lot number.11.4 Containers shall be free from any dirt, dust, oil, orother agents that may contaminate the material.11.5 Each individual spool shall be packaged in a suitableplastic bag, such as polyethylene.12. Keywords12.1 gloss-to-metal sealing; iron-nickel/copper compositewire; vacu
33、um electronicsNOTE 1The circular band represents the hues in their proper sequence. The upright center axis is the scale of value. The paths pointing outward fromthe center show the steps of chroma, increasing in strength as indicated by the numerals.FIG. 2 Hue, Value, and Chroma in Their Relationsh
34、ip to One AnotherF 29 97 (2002)3SUPPLEMENTARY REQUIREMENTSSUPPLEMENTARY NOTESNOTE S1For the purpose of calculating weights, cross sections, etc.,the density of the copper shall be taken as 8.89 g/cm3at 20C and thenickel-iron core as 8.12 g/cm3at 20C.NOTE S2Dumet is not generally used in sizes above
35、0.040 in. (1.0mm).NOTE S3Expansion values have been listed for information purposesonly.NOTE S4Several references and calculated values indicate the radialexpansion of dumet to be 90 3 107in./in.deg C (mm/mmdeg C) overthe temperature range of 25 to 400C.NOTE S5This material is intended for average a
36、pplications. It isrealized that for special cases a more precise definition of requirementsmay be necessary, but these are subject to individual agreement betweenthe manufacturer and the purchaser.NOTE S6Some users may require a metal-to-glass seal test similar tothat described in Practice F 14.NOTE
37、 S7Observed or calculated values obtained from analyses,measurements, or tests shall be rounded off in accordance with therounding-off method given in Practice E 29. These values shall be roundedoff to the nearest unit in the last right-hand place of figures used inexpressing the specified limit.AST
38、M International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are en
39、tirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsa
40、nd should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee
41、on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).F 29 97 (2002)4
