氧化鋁/氧化釔/氧化鋯複合材料與液態鈦金屬之介面反應

Abstract

以燒結法製備不同組成之Al2O3/Y2O3/ZrO2陶瓷試片，與鈦金屬在1 atm氬(Ar)氣氛下，進行1700℃與2小時之高溫擴散反應，探討在此參數下，陶瓷材料與鈦金屬高溫擴散介面反應之影響。本實驗用X光繞射儀(x-ray diffraction, XRD)、掃描式電子顯微鏡(SEM/EDS)，以及穿透式電子顯微鏡(TEM/EDS)，分析擴散後介面反應微觀結構。

各組陶瓷試片與鈦金屬經熔融擴散反應後，在鈦側處會產生鈦鋁合金，隨著氧化鋁比例上升而反應變劇烈，鈦側看到Ti、Zr置換後的Ti2ZrAl；而陶瓷深處則會產生許多化合物，其中包含：ZrO2、TiAl、Y3Al5O12(YAG)、YAlO3、Y2O3、Al3Zr…等。其中當氧化鋁比例含量超過pecolation threshold，便會在陶瓷裡形成內通路，鈦便可在此內通路進行擴散至陶瓷深處，因此整體抑制鈦擴散的效果非常差，造成微觀結構與其他組成差異非常大。

在其中4組與鈦熔融擴散反應後，發現YAG在擴散反應過程有著重要的角色，故將YAG特別討論，單獨跟Ti做高溫熔融擴散反應。

Various Al2O3/Y2O3/ZrO2 as sintering sample was reacted with titanium at 1700 °C/2 hr in argon. Analyzing the microstructure of the reaction interface was characterized with XRD, SEM/EDS, and TEM/EDS after reaction.

There were forming TiAl Alloys on Ti side after diffusion reaction, and the reactions were more violent with the Al2O3 content increase, so the phase transited to Ti2ZrAl by Zr took Ti place. So many compounds be observed, including ZrO2, TiAl, Y3Al5O12(YAG), YAlO3, Y2O3, Al3Zr, etc. When Al2O3 content exceed the percolation threshold, the interconnecting network would be formed. Due to Ti diffused into the ceramics deeply by this network, the microstructure different from the other specimens.

In four groups with the titanium melt diffusion reaction, the reaction in the diffusion process that YAG has an important role, it will be specifically discussed YAG and Ti melt diffusion reaction with the same temperature and time.