Gas turbine, or the jet engines have seen a rise in thrust output by increasing the chamber temperatures, advancement in compressor staging etc. On due of increased temperature limits, the turbine has particularly been subjected to higher thermomechanical stresses on the first stage high pressure stators, caused by the hot combustion product gases at high velocities. Thermal strains also get induced due to non-uniform temperature distribution from the hub to tip of the vanes. Improvements in material technologies to curb for higher temperatures have brought ceramic matrix composites into implementation. These are lighter in weight and have higher melting points than the conventionally used metal super alloys, with silicon carbide SiC/SiC matrix being specially used as the material for turbine stage of the engine. This consists of long unidirectional sic fibers as reinforcement, embedded in sic matrix phase, with fibre volume fractions in the range 30–40 percentages. But with further increase in thrust requirements, the turbine inlet temperature is also increased, affecting the material and the performance life of the component. Hence furthermore innovation in materials with higher strengths and melting points has to be incorporated. This work is on the use of vanadium carbide fibers as the reinforcement phase of silicon carbide matrix composite for the high pressure turbine stator. Structural analysis is carried out for the blade for both the composites, in ansys software using time stepped increment in temperature upto 1600°c. Results are compared to that for Sic/Sic composites. Thus the comparative analysis between the two composites is carried out on the thermo-structural aspect to predict their performance in the elevated temperatures.
Synthesis of Silicon Carbide Powders from Methyl-Modified Silica Aerogels
