A study on simultaneous measurement of thermophysical properties of solids by a direct
electrical heating method
August,1990
1ciro TAKAHASII
The plrpos,ヴ
thiS Study is to impFOVe a dむ ect electrical heating method so that L can
simultaneously obtain thermophysicd properties, such as thermal expansibn, olectricalresistivity,total helniSpherical emissivity,thermal cottducti,ity:ThO血
SO五 66efficient,sledifiC he誠 ,and therttal dttusiVity.Aui quantitieS requiredわr Obtaining thes6 properties‐
weredetermihed with a therrrlocOuple―
prObe ocanning bOth temperature― distributio,and vol,age―gradiё
nt in the longitudinal direction of rod samples.The influence of the thermal contact―
resistance at the contacting intel・
face b6tween the sample and the thё rlnOc6uple upon thё accuracy in lrleasuring temperatures was r9duCed by h,attng the therm6couple― probe and by∞ntro■
ing the temperature d ts tぃ OrmoCOuple to be eqtal to th■
of the sample:The tranlient temperature can be,ccurately obtained frOm cOrrecting tho output of the thermocouole by the correction一factor measured on the poriod of heating the sample in a cOnstant teコaperature.
Theoretical estimates of error caused by neg19Ct Of th6 tempel劉
比"e=distribution in the aross
―もしctiOn Of rod samples wore condicted.The effett Of the existence of the thermocouple―
prOb0 0n the radiative heat=f19w from the Surf
e of a sample was evaluatё
d by Cdcultting the configurat"nTfactors. The optimum sample,size wtt discussed on those theoretical analysosI The experimental results by using the rOd samples(3‑mln in idiameter)of」 IS・SUS304 and silver(purit,99.99%)Were presented and 9ompared with some litertture―
values
in thё temperature― range of roolrL t0 950 Ko The ability to apply this lnethoo thin ribbon samples was also demonstrated.
―=176‑一