Method of electrical resistivity measurement for high-temperature melts

Electrochemical Study of a Pendant Molten Alumina Droplet and Its Application for Thermodynamic Property Measurements of Al-Ir

“…More recently, Shatunov et al 63 reported conductivity by energy balance considerations using an induction-heated cold crucible in air. They reported 0.47 to 1.64 S cm −1 with 17% estimated error for T = 2573 to 3223 K. Their results are substantially lower than that of all previous measurements, which they attributed to impurities and atmosphere (oxygen potential).…”

“…Assessment of Al 2 O 3 conductivity.-Previous efforts to measure the electrical conductivity of Al 2 O 3 (l) are numerous, 21,[56][57][58][59][60][61][62][63] which is uncommon for refractory melts. Although recent researchers have compared their results with a partial selection of previous efforts, the last complete review of Al 2 O 3 (l) conductivity is that of Shpil'rain et al 60 More recent reviews, e.g., 67 have omitted without justification contributions from the aerodynamic levitation method.…”

“…Several workers reported measurements of σ for Al 2 O 3 (l) as a function of T in the literature. 21,[56][57][58][59][60][61][62][63] A critical assessment of these results in the temperature range T m (Al 2 O 3 ) = 2327 K 64,65 to T m (Ir) = 2719 K 65,66 is provided in Appendix C, yielding E σ = 1.67 +/−0.15 eV. At the minimum P L required for electrode insertion into the droplet, this condition is assigned the temperature T 0 = 2377 K, a 50 K superheat above T m (Al 2 O 3 ).…”

Application of neural network for real-time measurement of electrical resistivity in cold crucible

“…As shown in figure 1, the total power distribution is calculated by the MM for every single geometrical and electrical setup for whole mentioned resistivity range and its final value is obtained by inverse problem solution based on power measurement Figure 1 also shows the two possible solutions, whereby only one of them is real. Therefore, an additional condition has to be applied [4]. In addition, a second approach of measurement should be used in parallel to the first one, because an uncertainty of measurement is functionally dependent on the derivative of the balance curve, as shown in Figure 2.…”

“…The System requirements are strongly dependent on MM parameters, layout of the IS, required accuracy and time response. In our case a 2D MM has been chosen that can be described by (2) to (4) while taking into account a quasi-stationary field, where γ is an inverse value of electrical resistivity, which is obtained as the inverse problem solution from its progression range [4]. A single-valued electrical resistivity has been taken into account, due to inverse problem solution, in spite of temperature variations in the melt.…”