(上海交通大學(xué) 金屬基復(fù)合材料國家重點實驗室, 上海 200030)
摘 要: 利用鈦與B2O3、 B4C和稀土釔之間的化學(xué)反應(yīng)， 采用真空非自耗電弧爐熔煉工藝， 原位合成多元、 多尺度、 不同形狀增強(qiáng)體增強(qiáng)的鈦基復(fù)合材料——(TiB+TiC+Y2O3)/Ti。 利用熱力學(xué)機(jī)理分析了制備該種材料的可行性， 通過X射線衍射儀、 光學(xué)顯微鏡、 掃描電鏡、 電子探針和透射電鏡分析了復(fù)合材料的物相組成、 增強(qiáng)體的微觀形貌和材料的顯微組織。 結(jié)果表明： 復(fù)合材料的增強(qiáng)體為TiB、 TiC和Y2O3； 生成的增強(qiáng)體分布均勻； 復(fù)合材料的晶粒非常細(xì)小； TiB為針狀； TiC為等軸狀和近似等軸狀； Y2O3的形貌隨著稀土Y含量的增加從近似等軸狀粗化生長為樹枝狀； 材料中存在較多納米級的球狀增強(qiáng)體； 增強(qiáng)體TiB、 TiC、 Y2O3和鈦基體界面干凈， 沒有界面反應(yīng)物存在。
關(guān)鍵字: 原位合成； 鈦基復(fù)合材料； 多元增強(qiáng)體； 氧化釔； 顯微組織
（State Key Laboratory of Metal Matrix Composites,
Shanghai Jiaotong University, Shanghai 200030, China）
Abstract: The novel titanium matrix composites, (TiB+TiC+Y2O3)/Ti, which were reinforced with multiple ceramic particulates in different sizes and shapes, were synthesized by the chemical reaction among Ti, B2O3, B4C and rare earth metal Y by vacuum non-consumable arc-melting technique. The thermodynamical feasibility of the in-situ reactions has been analyzed. X-ray diffraction (XRD) was used to identify the phases in the composites. Microstructures of the composites were observed by means of optical microscope (OM), scanning electron microscope (SEM), electron probe and transmission electron microscope (TEM). The results show that the composites consist of Ti, TiB, TiC and Y2O3. The reinforcements are distributed uniformly in the matrix. The crystal grain of the composites is finer than that of pure titanium. TiB grows in needle shapes and TiC grows in equiaxed and near-equiaxed shapes. Y2O3 grows from near-equiaxed shapes to dendritic shapes with increasing the content of Y. Some sphere-shaped reinforcements with nanometer sizes exist in the composites. The interfaces between reinforcements of TiB, TiC and Y2O3 and Ti matrix are clear without any interfacial reactions.
Key words: in-situ synthesis; titanium matrix composite; multiple ceramic particulate reinforcements; Y2O3; microstructure
