STUDIES OF THERMOMETRIC MATERIAL Lu1-xZrxNiSb

• Published in: Measuring Equipment and Metrology 2022, Vol.83 (1), p.10-16
• Main Authors: Pashkevych, Volodymyr, Krayovskyy, Volodymyr, Rokomanyuk, Mariya, Haranuk, Petro, Romaka, Volodymyr, Stadnyk, Yurii, Romaka, Lyubov, Horyn, Andriy, Fruchart, Daniel
• Format: Article
• Language: English
• ISSN: 0368-6418; 2617-846X
• DOI: 10.23939/istcmtm2022.01.010

The results of experimental research of perspective thermometric material Lu1-xZrxNiSbwhich can be used for the production of sensitive elements of thermoelectric and electroresistive thermometers are presented. Thermometric materials Lu1-xZrxNiSb, x=0.01–0.10, were made by fusing a charge of components in an electric arc furnace with a tungsten electrode (cathode) in an atmosphere of purified argon under a pressure of 0.1 kPa on a copper water-cooled hearth (anode). Heat treatment of alloys consisted of homogenizing annealing at a temperature of 1073 K. Annealing of samples was carried out for 720 h in vacuumed up to 1.0 Pa ampoules of quartz glass in muffle electric furnaces with temperature control with an accuracy of ±10 K. Diffraction arrays were obtained on a diffractometer DRON-4.0 (FeKα radiation), and the structural characteristics of Lu1-xZrxNiSbwere calculated using the Fullprof program. The chemical and phase compositions of the samples were monitored using a scanning electron microscope (Tescan Vega 3 LMU). The study of the temperature dependences of the resistivity ρ(T,x) and the thermopower coefficientα(T,x) Lu1-xZrxNiSb was performed in the temperature range of 80÷400 K on samples in the form of rectangular parallelepipeds measuring ~1.0×1.0×5.0 mm3 . Measurements of the values of the specific magnetic susceptibility χ(x) of Lu1-xZrxNiSb samples were performed by the relative Faraday method at a temperature of 273 K using a thermogravimetric installation with an electronic microbalance EM-5-ZMP in magnetic fields up to 10 kGs. Microprobe analysis of the concentration of atoms on the surface of Lu1-xZrxNiSb samples, x=0.01–0.10, established their correspondence to the initial compositions of the charge, and X-ray phase analysis showed no traces of extraneous phases on the sample diffractograms, except for the main phase. The nonmonotonic nature of the change in the values of the unit cell period of the thermometric material an (x) Lu1-xZrxNiSb, x=0.01–0.10, which differs from the results of modeling structural characteristics using software packages AkaiKKR and Elk. The nonmonotonic change in the values of the period of the unit cell a(x) Lu1-xZrxNiSband the presence of the extremum dependence suggests that the impurity Zr atoms introduced into the matrix of the LuNiSb basic semiconductor can simultaneously occupy partially different crystallographic positions in different ratios. The temperature resistivities ρ and the thermopower coefficie