A tec hniqu e is described for th e hi gh•speed m e~s ure m e nt of heat capacit y, elec trical res istivit y, he mi s phe rical total and norm al spectral e mitta nces of electri cal condu ctors at high te mpe ra tures (above 1900 K) with milli second resolution. Duration of a n individ ual experim e nt , in which t he s pecim e n is he a ted from r oo m te mperatu re to cl ose to its meltin g po int, is less tha n one second. T e mpera ture m eas ureme nts a re made with a highs peed photoelec tri c pyr ome ter. Quantiti es are recorded by a hi gh•s peed di gita l data acqui s ition sys te m whic h has a resolutio n of ap proximately one pa rt in 8000. T ime resolutio n of th e entire syste m is 0.4 ms. Results on th e abo ve prope rties of molybd enum in th e te mpe rature ra nge 1900 to 2800 K are re ported a nd are co mpared with th ose in the literature. Estimated inacc uracy of measl're d pro pe rti es in the a bove te mperature ra nge is: 2 to 3 per cent for heat capacity, 0.5 pe rce nt fo r electrical res isti vit y, 3 perce nt fo r he mi s ph e ric al total emittance and 2 percent for no rm al spectral e mittance. Key word s: El ectrical res isti vi ty; e mitta nce; heat ca pac ity; hi g h-s peed meas ure me nts; high tem pe ratu re; mo lybde num ; th e rm a l radi ati on pro pe rties; the rm od yna mics.

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.

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S imultaneous meas ure me nt s of hea t ca pac ity, e lec tri ca l res istivity and hemisphe ri c al total e mit· tan ce of iron (99 .9 0/0 pure) in th e te mperature ran ge 1500 to 1800 K. and the meltin g point of iron by a s ubseco nd dura tion, tran s ie nt tec hnique are desc ribe d. The meas ureme nt s indi cate inc reases in heat ca pac ity and elec tri ca l resistivity as the res ult of th e so lid ·solid phase tran s formation (y--> Il) in iron. The meas ure d value of th e he mis ph e ri ca l total e mittan ce at 1720 K is 0. 33. Th e average of the results of two e xperim e nts yie ld a value of 1808 K for th e meltin g point of iron. Es timated in accuracies of meas· ure d pro perties are: 3 percent for heat ca pacity and e mittan ce, I pe rce nt for e lec tri cal res is tivity , and 5 K for the melting point.Key words : Elec trical resis tivit y; e mittan ce; heat ca pacity; hi gh·s peed meas ure ments; hi gh te mpe ra· ture; iron ; meltin g point; phase tran s formation ; th e rm ody nam ics; thermo physi ca l properties.