ASTM_E_1409_-_13.pdf

Designation:E140913Standard Test Method forDetermination of Oxygen and Nitrogen in Titanium andTitanium Alloys by Inert Gas Fusion1This standard is issued under the fixed designation E1409;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 test method covers the determination of oxygen intitanium and titanium alloys in mass fractions from 0.01%to0.5%and the determination of nitrogen in titanium andtitanium alloys in mass fractions from 0.003%to 0.11%.1.2 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 establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.Specific warningstatements are given in 8.8.2.Referenced Documents2.1 ASTM Standards:2E50 Practices for Apparatus,Reagents,and Safety Consid-erations for Chemical Analysis of Metals,Ores,andRelated MaterialsE135 Terminology Relating to Analytical Chemistry forMetals,Ores,and Related MaterialsE173 Practice for Conducting Interlaboratory Studies ofMethods for Chemical Analysis of Metals(Withdrawn1998)3E1601 Practice for Conducting an Interlaboratory Study toEvaluate the Performance of an Analytical Method3.Terminology3.1 DefinitionsFor definitions of terms used in thismethod,refer to Terminology E135.4.Summary of Test Method4.1 This test method is intended for use with automated,commercially available,inert gas fusion analyzers.Theseanalyzers typically measure both oxygen and nitrogen simul-taneously or sequentially utilizing parallel measurement sys-tems.4.2 The test sample,plus flux,is fused in a graphite crucibleunder a flowing inert gas stream at a temperature sufficient torelease oxygen and nitrogen.Oxygen combines with carbon toform carbon monoxide(CO)and nitrogen is released as N2.Depending on instrument design,the CO may be oxidized tocarbon dioxide(CO2).The CO or CO2,or both,are swept bythe inert gas stream into either an infrared or thermal conduc-tivity detector.The detector response generated by analysis ofthe test sample is compared to the response generated byanalysis of reference materials and the result is displayed aspercent oxygen.The nitrogen is swept by the inert gas streaminto a thermal conductivity detector.The detector responsegenerated by analysis of the test sample is compared to theresponse generated by analysis of reference materials and theresult is displayed as percent nitrogen.4.3 In a typical instrument for the determination of nitrogen,the sample gases are swept with inert gas through heated rareearth/copper oxide that converts CO to CO2and hydrogen(H2)to water(H2O).The CO2is absorbed on sodium hydroxideimpregnated on clay,and the H2O is removed with magnesiumperchlorate.The nitrogen,as N2,enters the measuring cell andthe thermistor bridge output is integrated and processed todisplay percent nitrogen.5.Significance and Use5.1 This test method is primarily intended as a test forcompliance with compositional specifications.It is assumedthat all who use this test method will be trained analystscapable of performing common laboratory procedures skill-fully and safely.It is expected that the work will be performedin a properly equipped laboratory.6.Interferences6.1 The elements usually present in titanium and its alloysdo not interfere but there is some evidence to suggest that lowpurity flux can cause some adsorption of the released oxygen.7.Apparatus7.1 InstrumentFusion and measurement apparatus,auto-matic oxygen and nitrogen determinator consisting of an1E01 on Analytical Chemistry for Metals,Ores,and Related Materials and is thedirect responsibility of Subcommittee E01.06 on Ti,Zr,W,Mo,Ta,Nb,Hf,Re.Current edition approved Oct.1,2013.Published November 2013.Originallyapproved in 1991.Last previous edition approved in 2008 as E1409 08.DOI:10.1520/E1409-13.2For 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.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 electrode furnace,provision for scrubbing impurities fromanalytical gas stream;infrared or thermal conductivity mea-surement system(s),or both,and auxiliary gas purificationsystems(Note 1).NOTE1Several models of commercial oxygen and nitrogen determi-nators are available and presently in use by industry.Each has its ownunique design characteristics and operational requirements.Consult theinstrument manufacturers instruction manual for