Reactions of Titanium Dioxide and Copper at High Temperature

• Main Authors: Fang, Fuxuan, 方復宣
• Other Authors: Fu-Hsing Lu
• Format: Others
• Language: zh-TW
• Published: 1998
• Online Access: http://ndltd.ncl.edu.tw/handle/99298199037098310474

碩士 === 國立中興大學 === 材料工程學研究所 === 86 === In this research, we investgated the changes of the microstructure in the reactions between Cu and TiO2 at high temperature. The effects of the oxygen partial pressure on the reaction are discussed. The following gases used air, N2/O2=9, N2 and N2/H2=9. We analyzed the resulting changes in the topography and the composition by using optical microscop, SEM, EDS, etc. The microstructural changes were characterized by XRD. Copper was first embeded and in the TiO2 powder and then cold pressed, The samples were heated at 1000℃ for 30 minutes. Results show that samples melted and TiO2 turned from white to black. The microstructures were found to be CuO and TiO2. When copper was placedon the top of TiO2 and then heated up at 1000℃ for 30 minutes in air. Results also show that samples melted. Since the eutectic point of CuO and TiO2 might be lower than 1000℃, copper would first oxidezed into CuO then diffuse in liquid state into TiO2.At 1000℃ copper samples were placed on the top of TiO2 for 5 minutes to 25 minutes. The whisker-like material appeared on the top of copper surface and grew with time. The whisker-like material might be mainly CuO after analysis. In the atmosphere of N2/O2=9, we keep the temperature at 1000℃ for 3 hr .The samples of the copper embeded and pressed by TiO2 powder became black. The structures were CuO and TiO2 and the copper melted but not as dramatic as in air. The samples of copper embeded and then cold pressed by TiO2 powder were heated at 1000℃ for 3 hrs in N2 atmosphere. The copper surface oxidized into Cu2O and the color of TiO2 became red. And the structure was TiO2 only. Copper were preheated at 1000℃for 9 hrs and then embeded and pressed by TiO2 and heated at 1055℃ and 1075℃. The color of TiO2 became red and the structure was only TiO2 still. The copper melted at 1075℃. It is because that 1075℃ is higher than the eutectic point of Cu2O and Cu. It''s 1065℃. Copper embeded and cold pressed by TiO2 are heated at 1000℃ for 3 hrs and 12hrs in N2/ H2=9 atmosphere. The structures were Cu and TiO2. There was no obvious reaction occurred.