Attempts have been made to quantify the amount of contaminants absorbed by liquid metal from commercial ZrO 2 -, Al 2 O 3 -, and SiC-base crucibles used for vacuum melting of Ni-45 wt pct Ti alloy. The molten alloy was held under vacuum for 90 minutes at 1450 °C to become homogenized. Reactions between the liquid metal and the crucible were investigated by visual observation, chemical analysis, scanning electron microscopy (SEM) image processing, and X-ray mapping. The relative degree of contamination declined in the following sequence: commercially pure SiC Ͼ SiC-5 wt pct Al 2 O 3 -5 wt pct SiO 2 Ͼ slurry cast alumina Ͼ recrystallized alumina Ͼ zircon type A Ͼ oxygen deficient high-purity zirconia. Thermodynamic calculations showed a difference between the equilibrium and the experimental data, indicating that except for commercially pure SiC crucible, the amount of the crucible elements entering the melt is greater than the calculated equilibrium values. This discrepancy seems to be due to the immersion into the melt of the undissolved chemical compounds formed due to the reactions between the crucible and the liquid phase.

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In the present research work, the newest economic method for synthesis of ZnO nanopowder has been carried out via solochemical processing from an aqueous solution of a zinc-containing complex. The results obtained from XRD and TEM show that the nanoparticles are single crystals and have elongated particulate shape with a narrow size distribution. Solochemical processing can thus be an attractive method for industrial production of the nanopowders. The highly textured ZnO thin film with a preferred (002) orientation was also prepared by Two-Stage Chemical Deposition (TSCD), using an aqueous solution containing zinc complex on a soda-lime glass substrate. The films were characterised by XRD, SEM, EDAX, optical spectrophotometer and FTIR to justify the suitability for commercial device quality.

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