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In the present work, the microstructure, phase constitution, and corrosion behavior of binary Sn-xZn alloys (x = 5, 9 and 15 wt.%) were investigated. The alloys were prepared by induction melting of Sn and Zn lumps in argon. After melting, the alloys were solidified to form cast cylinders. The Sn-9Zn alloy had a eutectic microstructure. The Sn-5Zn and Sn-15Zn alloys were composed of dendritic (Sn) or (Zn) and eutectic. The corrosion behavior of the Sn-Zn alloys was studied in aqueous HCl (1 wt.%) and NaCl (3.5 wt.%) solutions at room temperature. Corrosion potentials and corrosion rates in HCl were significantly higher compared to NaCl. The corrosion of the binary Sn-Zn alloys was found to take place by a galvanic mechanism. The chemical composition of the corrosion products formed on the Sn-Zn alloys changed with the Zn weight fraction. Alloys with a higher concentration of Zn (Sn-9Zn, Sn-15Zn) formed corrosion products rich in Zn. The Zn-rich corrosion products were prone to spallation. The corrosion rate in the HCl solution decreased with decreasing weight fraction of Zn. The Sn-5Zn alloy had the lowest corrosion rate. The corrosion resistance in HCl could be considerably improved by reducing the proportion of zinc in Sn-Zn alloys.

The strain behavior of SiC/Stycast 2850 FT composites under thermomechanical loading using a finite element analysis (FEA) was studied. These composites can serve as thermal stabilizers of high-temperature superconducting (HTS) tapes during limitation event in resistive superconducting fault current limiter (R-SCFCL) applications. For this purpose, the thermomechanical properties of four composite systems with different filler content were studied experimentally. The FEA was calculated using an ANSYS software and it delivered useful information about the strain distribution in the composite coating, as well as in particular layers of the modified HTS tapes. The tapes were subjected to bending over a 25 cm core, cooled in a liquid nitrogen (LN2) bath, and finally, quenched from this temperature to various temperatures up to 150 °C for a very short time, simulating real limitation conditions. The outputs from simulations were also correlated with the experiments. The most promising of all investigated systems was SB11-SiC20 composite in form of 100 µm thick coating, withstanding a temperature change from LN2 up to 120 °C.