1、Designation: B267 07 (Reapproved 2018)Standard Specification forWire for Use In Wire-Wound Resistors1This standard is issued under the fixed designation B267; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers round wire and ribbon withcontrolled electrical properties for use in wire-wound resis-tance units and s
3、imilar applications, but not for use as electricalheating elements.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.1.3 This standard
4、does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to become familiarwith all hazards including those identified in the appropriateSafety Data Sheet (SDS) for this product/material as providedby the manufacture
5、r, to establish appropriate safety, health,and environmental practices, and determine the applicabilityof regulatory limitations prior to use.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Pri
6、nciples for theDevelopment of International Standards, Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade (TBT) Committee.2. Referenced Documents2.1 ASTM Standards:2B63 Test Method for Resistivity of Metallically ConductingResistance and Contact MaterialsB7
7、7 Test Method for Thermoelectric Power of Electrical-Resistance AlloysB84 Test Method for Temperature-Resistance Constants ofAlloy Wires for Precision Resistors3. Significance and Use3.1 This specification on wire and ribbon contains thegeneric chemistry and requirements for resistivity, temperature
8、coefficient of resistance, thermal emf versus copper resistancetolerances, and mechanical properties of bare wire, as well asthe wire enamels and insulations of alloys normally used in themanufacture of wound resistors.4. Alloy Classes4.1 Fifteen classes of alloys are covered by this specificationas
9、 listed in Table 1.5. Elongation5.1 The wire shall conform to the requirements for elonga-tion as prescribed in Table 1, when tested on a 10-in. (254-mm)length.6. Resistivity6.1 The bare wire shall conform to the requirements fornominal resistivity as prescribed in Table 1.6.2 Actual resistivity sha
10、ll not vary from nominal resistivityby more than 65 % for Alloy Classes 1 to 4 inclusive, and610 % for Alloy Classes 5 to 11 inclusive.7. Nominal Electrical Resistance per Unit Length7.1 The nominal resistance per unit length for round wireshall be calculated from the nominal resistivity and the nom
11、inalcross-sectional area.NOTE 1When ribbon or flat wire is produced by rolling from roundwire, the cross section departs from that of a true rectangle by an amountdepending on the width-to-thickness ratio and the specific manufacturingpractice. The conventional formula for computing ohms per foot an
12、d feetper pound is to consider the cross section as 17 % less than a true rectanglewhen width is more than 15 times the thickness and 6 % less than a truerectangle in other cases. This is not valid in view of modern rollingequipment and practices, but still is widely used as a basis of description.R
13、ibbon actually is made to a specified resistance per foot, and no toleranceis specified for thickness.An alternative and a closer approximation wouldbe that for ribbon rolled round wire, the electrical resistance would becalculated on a cross 6 % less than a true rectangle.8. Temperature Coefficient
14、 of Resistance8.1 The change in resistance with change in temperature,expressed as the mean temperature coefficient of resistance1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.10 on Thermostat Met
15、als and Electrical Resistance Heating Materials.Current edition approved April 1, 2018. Published April 2018. Originallyapproved in 1952. Last previous edition approved in 2013 as B267 07 (2013).DOI: 10.1520/B0267-07R18.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact
16、ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United StatesThis international standard
17、was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.1TABLE 1 Cl
18、asses of Alloys and RequirementsAlloyClassAAlloy Composition,approximate, %Resistivity,cmil/ft(m)Mean Temperature Coefficient of Resistance, mppm forC Over Temperature Range, TMaximum Thermal emfversus Copper, mV/CBElongation in 10 in., min, %T mT mV/CTemperatureRange, TCOver0.002in.DinDiameter0.002
19、 to0.001in.DinDiameter0.0009in.DinDiameterand Finer12 3 456789101121a nickel base, nonmagnetic 800 (1.330) 0, 20 +25 to 55 0, 20 +25 to +105 +0.003 65 to +250 10 5 31b nickel base, nonmagnetic 800 (1.330) 0, 10 +25 to 55 0, 10 +25 to +105 +0.003 65 to +150 10 5 31c nickel base, nonmagnetic 800 (1.33
20、0) 0, 5 +25 to 55 0, 5 +25 to +105 +0.003 65 to +150 10 5 32a iron base, magnetic 800 (1.330) 0, 20 +25 to 55 0, 20 +25 to +105 0.004 65 to +200 10 5 32b iron base, magnetic 800 (1.330) 0, 10 +25 to 55 0, 10 +25 to +105 0.004 65 to +150 10 5 33a 80 nickel, 20 chromium 650 (1.081) +80, 20 +25 to 55 +
21、80, 20 +25 to +105 +0.006 65 to +250 15 5 33b 80 nickel, 20 chromium,stabilized675 (1.122) +60, 20 +25 to 55 +60, 20 +25 to +105 +0.006 65 to +250 15 5 34 60 nickel, 16 chromium,balance iron675 (1.122) +140, 30 +25 to 55 +140, 30 +25 to +105 +0.002 65 to +200 15 5 35a 55 copper, 45 nickel 300 (0.499
22、) 0, 20 +25 to 55 0, 20 +25 to +105 0.045 65 to + 150 15 5 35b 55 copper, 45 nickel 300 (0.499) 0, 40 +25 to 55 0, 40 +25 to +105 0.045 65 to +150 15 5 36 manganin type 290 (0.482) 0, 15EE0, 15EE0.003 +15 to +35 15 5 37 77 copper, 23 nickel 180 (0.299) +180, 30 +25 to 55 +180, 30 +25 to +105 0.037 6
23、5 to +150 15 5 38 70 nickel, 30 iron 125 (0.199) +3600, 400 +25 to 50 +4300, 400 +25 to +104 0.040 50 to +100 15 5 39 90 copper, 10 nickel 90 (0.150) +450, 50 +25 to 55 +450, 50 +25 to +105 0.026 65 to +150 15 5 310 94 copper, 6 nickel 60 (0.100) +700, 200 +25 to 55 +700, 200 +25 to +105 0.022 65 to
24、 +150 15 5 311 98 copper, 2 nickel 30 (0.050) +1400, 300 +25 to 55 +1400, 300 +25 to +105 0.014 65 to +150 15 5 3AAlloy Classes 1a to 8 inclusive are designed to provide controlled temperature coefficients. Values shown for other classes are for information only. All values are basedon a reference t
25、emperature of 25C.BAlloy Classes 1a, 1b, 1c, 2a, 2b, 3a, 4, and 6 are designed to give a low emf versus copper. Values shown for other classes are for information only. Maximum indicatesthe maximum deviation from zero and the plus or minus sign the polarity of the couple.CThe maximum temperature val
26、ues listed apply to the alloy wire only. Caution should be exercised pending knowledge of the maximum temperature of use for the coatingmaterial involved.DIf metric sizes are desired, 1 in. = 25.4 mm.EAlloy Class 6 (manganin type for resistors), has a temperature-resistance curve of parabolic shape
27、with the maximum resistance normally located between 25 and 30C.Thus, Columns 5 and 7 cannot indicate 25C as a limit but mmay be expressed as a maximum of +15 ppm for 15C to the temperature of maximum resistance and amaximum of 15 ppm from the temperature of maximum resistance to 35C. All of the inf
28、ormation included in this note is based on measurements made in accordancewith Test Method B84.TABLE 2 Dimensions of Enamel Coated WireANominal Bare Wire Size Light Coated Wire Medium Coated Wire Heavy Coated WireB resistivity; resistor alloys; resistors;wire woundASTM International takes no positio
29、n 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 entirely their own responsibility.
30、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 standardsand should be addressed to ASTM I
31、nternational 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 on Standards, at the address sho
32、wn 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). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 07 (2018)5
