Influence of processing variables on the formation of La2Zr2O7 in transferred arc plasma torch processing

The transferred arc plasma (TAP) torch process has various noteworthy features such as extremely hightemperatures, low environmental impact and short processing time which makes it the most suitabletechnique for synthesizing ceramic composite materials. Furthermore, it is a direct two-step techniquewhich by its virtue of high temperature and power density paves way for high production rate. Hence inthis study, an effort has been made to utilize the TAP torch processing technique for the bulk productionof La2Zr2O7 with time effectiveness from the mixture of La2O3 and ZrO2 powders (1:2 mol ratios) whichwere ball milled for 4 h. For this purpose, transferred arc plasma torch was specially designed inlaboratory scale level and the operating parameters were optimized in order to achieve maximumLa2Zr2O7 formation efficiency. In this study, the phase and microstructure formation of the processedsamples was analyzed via X-ray diffraction (XRD) and scanning electron microscope (SEM) imagesrespectively. Moreover, EDX analysis was incorporated to highlight the superior influence of the longerprocessing time on the stoichiometric ratio of ZrO2/La2O3 in the processed sample as against input powerand the gas flow rate.