Influence of Various Conditions of Convective Mixing of Melt on the Structure and Magnetoresistance of Eutectic InSb–NiSb Alloys Obtained by Directional Crystallization

摘要

The microstructures are analyzed of the eutectic alloys solidified in the quasi-binary InSb–NiSb system under different conditions of convective mixing of melts grown in an ampoule by the Czochralski and directional crystallization methods under earth and microgravity conditions. It is established that growth of the phases in directional solidification of the InSb–NiSb eutectics is determined not only by the diffusion mechanism of the component redistribution at the crystallization front but also by the diffusion–convection mechanism. The comparative analysis of the influence of the crystal microstructure on the value of the magnetoresistance, R_M, is performed for the first time. It is shown that the R_M value of directionally crystallized InSb–NiSb eutectics depends on the density of the NiSb needles, disorder of the eutectic structure, and electrophysical parameters of the matrix.