(東北大學(xué) 材料與冶金學(xué)院， 沈陽(yáng) 110004)
摘 要: 以反應(yīng)燒結(jié)的O′-Sialon和金紅石型TiO2為研究對(duì)象， 設(shè)計(jì)制備了TiO2/O′-Sialon擴(kuò)散偶， 采用X射線衍射(XRD)、掃描電鏡(SEM)及電子探針微區(qū)分析(EPMA)等方法， 對(duì)擴(kuò)散偶的擴(kuò)散界面及垂直于界面的斷面進(jìn)行了物相分析、形貌觀察及元素面分布分析， 并在此基礎(chǔ)上探討了TiO2/O′-Sialon界面反應(yīng)過程。 XRD結(jié)果表明： TiO2與O′-Sialon在界面處發(fā)生反應(yīng)生成TiN和SiO2， 但在1 200 ℃時(shí)擴(kuò)散反應(yīng)程度微弱， 界面處存在Sm2O3偏析， 并且與SiO2生成Sm2Si2O7； SEM照片顯示TiO2/O′-Sialon界面處存在不規(guī)則硅酸鹽熔融層； EPMA元素面分布分析表明Ti、 Si等元素富集于硅酸鹽熔融層內(nèi)， 只有微量元素?cái)U(kuò)散至基體內(nèi)。 綜合分析結(jié)果得出， TiO2/O′-Sialon界面反應(yīng)過程可分為三個(gè)階段：物理接觸階段、 熔融層形成及元素富集階段、 熔融層增長(zhǎng)階段。
關(guān)鍵字: TiO2/O′-Sialon； 擴(kuò)散偶；界面反應(yīng)； 電子探針
TiO2 and O′-Sialon
（ School of Materials and Metallurgy, Northestern University,
Shenyang 110004, China）
Abstract: TiO2/O′-Sialon diffusion couple was designed and prepared with reactive sintered O′-Sialon and rutile TiO2 as raw materials. The phases of interface and cross-section phases were determined by XRD and morphology and element section distribution were analyzed by SEM and EPMA. On the base of information obtained above, the reactive process in the interface of TiO2/O′-Sialon diffusion couple was discussed. The results of XRD show that TiO2 reacts with O′-Sialon in the interface, which produces TiN and SiO2, but the degree of the reaction is weak at 1 200 ℃, gravity segregation of Sm2O3 is found and Sm2Si2O7 is generated by Sm2O3 and SiO2 in the interface; and irregular fusion zone is observed in the interface through SEM; the analysis of element distribution by EPMA states that element Si and Ti enrich in the zone but there is only micro-element diffusion to the base. The conclusion is obtained by analysis mentioned that the reactive process can be divided into three stages: physical contact, formation of fusion zone and element-enrichment, growth of fusion zone.
Key words: TiO2/O′-Sialon; diffusion couple; interface reaction; electron probe
