High-speed (subsecond) measurement of heat capacity, electrical resistivity, and thermal radiation properties of tungsten in the range 2000 to 3600 K

Meas ure me nt s of heat capacit y, e lec tri cal res istivit y, he mi s ph e ri ca l tota l e mittan ce, a nd norm a l s pec tral e mittan ce of tungste n a bove 2000 K by a pulse heatin g tec hni q ue a re desc rib ed .Durat ion of a n in d ividu a l ex pe rim ent , in whic h th e s pec im e n is heated from roo m te mperature to nea r its me ltin g point , is less th a n one seco nd .Te m pe rature meas ure me nt s a re ma de with a photoe lec tri c pyrome te r.Experim e nta l q ua ntiti es a re reco rd ed with a d igita l da ta acq uis iti on sys te m , whi c h has a fu ll •scal e s igna l resoluti on of one part in 8000.Tim e resoluti on of th e e ntire syste m is 0.4 m s.Res ults on th e above prope rti es of tun gs te n in th e ra nge 2000 to 3600 K a re re port ed a nd are co mpare d with t hose in th e lite ra ture.E stim a ted in acc uracy of meas ure d properties in th e above te mp erature ra nge is: 2 to 3 pe rce nt for heat ca pac ity , 1 perce nt for e lectri cal resis ti vit y , 3 pe rce nt for hemi sphe ri ca l total a nd no rm a l spec tral em itta nces.Key word s : E lect.ri ca l resis tivity; e mitta nce; heat ca pa cit y; hi gh•speed meas ureme nts; hi gh te mp e ra• t.ure; th e rma l radiation p roperti es; th e rm od ynamics: tun gs te n. *This work was s upport ed in part by the Direc tora te of Aeromec han ics a nd Ene rgeti cs .U.S. Air Force Offi ce of Sci en Ii fie Hesea rch und e r contra ct ISSA -70-0002.1 Figures in brac ke ts ind icate th e lit e rature refe rences allhe e nd of thi s pape r.of rela tion s for properties e tc., a re give n in earli er publi cations [2,3] in co nn ection with m eas ure me nts on molybdenum and tantalum.