| 초록 |
Zirconia is a heat-resistant material with a high melting temperature(2700℃) and has low thermal conductivity and excellent corrosion resistance. However, application has been limited due to brittleness, which is a disadvantage of ceramic materials. As a way to improve this, the addition of Y3+ improves the strength by phase transformation, which can improve the brittle problem, which is a disadvantage of ceramic. Many studies have been conducted on the addition of Y3+ after the addition has been found to be more efficient than the other additives. In this experiment, have studied the additives that replace this Y3+. Expeiments on the possibility of replacing Y3+ by adding an alternative additive considering Zr-sol(Fe2+, Fe3+, Er3+) in consideration of Atomic size, Crystal ionic raddi and Effective Ionic raddi. ZOC(ZrOCl2*8H2O) was dissolved in distilled water and synthesized by hydrothermal synthesis at 160℃ for 24 hours. The formed Zr-sol was separated into a supernatant and precipitate. The supernatant was washed with distilled water, and the presence of chloride ion was confirmed using AgNO3. And add to the cleaned Zr-sol an additive that is believed to be a substitute for Y3+. The prepared Zirconia was calcined at 900℃ for 2hours, and the crystal phase was analyzed by XRD similar that of YSZ. The calcined powder was uniaxial pressed and sintered at 1500℃ for 2hours. The sintered specimens were first measured for specific gravity. And the particle size distribution, EDAX and FESEM were measured. |
