二氧化鈦/氧化鈣/氧化釔陶瓷材料與熔融鈦界面反應

Abstract

本研究將不同比例的 TiO2/CaO/Al2O3 粉末相互混和，並以 1300°C /30min 的條件熱壓成陶瓷複合試片後，分別形成 CaTiO3 單體以及三種不同比例 Al2O3/CaTiO3 複合材料，在 1atm 氬 (Ar) 保護氣氛下，與鈦進行1500°C/6hour 的高溫界面反應。本研究以 X 光繞射儀 (XRD) 和掃描式電子顯微鏡 (ASEM) 來分析界面微觀結構，並探討陶瓷材料與鈦高溫界面反應之生成機構。 本研究發現所有陶瓷試片與 Ti 高溫界面反應後，鈦側因氧和鈦的親和力很大，氧會往鈦側擴散，生成固溶氧的 α-Ti ，而鈣幾乎不溶於鈦內，也不跟鈦反應。陶瓷側因為氧往鈦側擴散，靠近界面處的陶瓷氧化物會有缺氧現象。在三種不同比例的熱壓 Al2O3/CaTiO3 複合材料中，當 Al2O3 體積比例為 10%時，鋁不會擴散至鈦側，只會固溶進 CaTiO3，形成 Ca(Ti, Al)O3。當 Al2O3 體積比例大於 30%， Al2O3 會使我們的陶瓷試片有融化的現象發生，這是因為 Al2O3 與殘存的 CaO 發生一連串的反應，產生熔點較低的化合物 CaAl2O4。以及剩下的 Al2O3 和鈦的氧化物。

Various proportions of TiO2 / CaO / Al2O3 powders were mixed and hot pressed at 1300°C for 30min. These hot-pressed specimens reacted with the commercially pure titanium at 1500°C for 6hour in 1 atm argon atmosphere. The high temperature interfacial reactions were explored between each ceramic specimen and titanium metal. The interface microstructures were analyzed using an X-ray diffraction diffractometer (XRD) and an analytic scanning electron microscope (SEM/EDS). When ceramic specimens reacted with titanium at 1500°C for 6hour, the oxygen would be dissolved to the titanium to form α-Ti due to the great affinity between oxygen and titanium, resulting in the hypoxia phenomenon in the ceramic side near the interface. In the CaTiO3 specimens incorating with Al2O3. When the ceramic specimens with the volume ratio of Al2O3 was 10%. Al will not diffus to Ti. It dissolves in CaTiO3, and form Ca (Ti, Al) O3. When the ceramic specimens with the volume ratio of Al2O3 was more than 30%. There were melted phenomenon in the specimens. Because the chain reaction of the residual CaO and Al2O3, resulting in a lower melting point compounds. As well as the titanium oxide and Al2O3 will produce again.