ASTM_B_603_-_07_2013.pdf

Designation:B60307(Reapproved 2013)Standard Specification forDrawn or Rolled Iron-Chromium-Aluminum Alloys forElectrical Heating Elements1This standard is issued under the fixed designation B603;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.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 annealed,drawn,or rolledshapes for electrical heating and resistance purposes of alloysconsisting mainly of iron,chromium,and aluminum as detailedin Table 1.1.2 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 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 appropriateMaterial Safety Data Sheet(MSDS)for this product/materialas provided by the manufacturer,to establish appropriatesafety and health practices,and determine the applicability ofregulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2A751 Test Methods,Practices,and Terminology for Chemi-cal Analysis of Steel ProductsB63 Test Method for Resistivity of Metallically ConductingResistance and Contact MaterialsB70 Test Method for Change of Resistance With Tempera-ture of Metallic Materials for Electrical HeatingB78 Test Method of Accelerated Life of Iron-Chromium-Aluminum Alloys for Electrical Heating3.Terminology3.1 Definitions:3.1.1 lot size,nthe lot size for determining compliancewith the requirements of this specification shall be one heat.4.Significance and Use4.1 This specification on iron-chromium-aluminum alloyscontains the requirements for chemistry,electrical resistance,mechanical properties,resistance change with temperature,andpackaging.4.2 Determination of properties is not required for routineacceptance of material unless specified by the purchaser.5.Chemical Requirements5.1 The alloys shall conform to the requirements as tochemical composition prescribed in Table 1.5.2 Samples for Chemical AnalysisSpecimens for chemi-cal analysis may be taken either from the melt or from a sampleof finished material that is representative of the lot.5.3 Chemical AnalysisThe chemical analysis shall bemade in accordance with accepted practices.See Test MethodsA751.6.Physical Requirements6.1 The material shall be thoroughly and uniformly an-nealed.6.2 Wire shall conform to the following elongation require-ments:SizeElongation in10-in.(250-mm)minimum,%0.0035 in.(No.39 Awg)(0.089 mm)and larger120.0031 to 0.0020 in.(Nos.40 to 44 Awg)(0.079 to 0.015 mm)67.Nominal Resistivity7.1 The nominal resistivity shall be the resistivity of thewire as quenched from a temperature above 1450F(788C).The numerical values of the resistivity range at 77F(25C)shall be as shown in Table 1.8.Test for Resistivity8.1 The resistivity shall be determined in accordance withTest Method B63.1This specification is under the jurisdiction of ASTM Committee B02 onNonferrous Metals and Alloys and is the direct responsibility of SubcommitteeB02.10 on Thermostat Metals and Electrical Resistance Heating Materials.Current edition approved May 1,2013.Published May 2013.Originallyapproved in 1975.Last previous edition approved in 2007 as B603 07.DOI:10.1520/B0603-07R13.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact 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 States1 9.Nominal Electrical Resistance for Unit Length9.1 The nominal resistance per unit length for round wireshall be calculated from the nominal resistivities and thenominal cross-sectional area.NOTE1Actual values of resistivity and resistance change withtemperature have not been tabulated as they vary considerably with minorcomposition differences.Individual manufacturers should be contacted fordetailed information regarding their properties.NOTE2When 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 and feetper pound is to consider the cross section as 17%less than a true rectanglewhen a 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.Ribbon actually is made to a specif