Precursor-Derived Nanostructured Silicon Carbide Based Materials for Magnetohydrodynamic Electrode Applications
Development of suitable materials for use in a magneto-hydro-dynamic (MHD) generator is a challenging task. Extremely high temperatures coupled with highly corrosive seed-laden atmosphere limit the choice of materials in contact with the high temperature plasma to just a few materials. These materials are simultaneously subjected to stresses of mechanical, thermal, chemical, electrical and high temperature-electromagnetic nature. In this work, a novel class of silicon carbide (SiC) based ceramic composite materials with compositions tailored through a polymer precursor derived synthesis route was developed. SiC has a strong covalent bonding character, resulting in high values of mechanical strength, high hardness and chemical stability while retaining good electrical properties at elevated temperatures. Since a unique feature of the precursor-derived materials was the presence of crystalline SiC domains separated by nanoscale carbon, feasibility of materials for electrodes that need to withstand at extremely high temperatures while maintaining good mechanical and electrical properties was investigated.