BaZrO_(3)/Al_(2)O_(3)复合模壳与Ti-46Al-8Nb熔体界面反应机理  

Interfacial Reaction Between BaZrO_(3)/Al_(2)O_(3)Composite Mould and Ti-46Al-8Nb Melt

作　　者：毛露 杨宇辰 陈光耀 段保华 李海涛 冯齐胜 鲁雄刚 李重河 MAO Lu;YANG Yuchen;CHEN Guangyao;DUAN Baohua;LI Haitao;FENG Qisheng;LU Xionggang;LI Chonghe(State Key Laboratory of Advanced Special Steel&Shanghai Key Laboratory of Advanced Ferrometallurgy,School of Materials Science and Engineering,Shanghai University,Shanghai 200072,China;Shanghai Special Casting Engineering Technology Research Center,Shanghai 201605,China;School of Materials Science and Engineering,Shanghai DianJi University,Shanghai 201306,China)

机构地区：[1]上海大学材料科学与工程学院,省部共建高品质特殊钢冶金与制备国家重点实验室,上海市钢铁冶金新技术开发应用重点实验室,上海200072 [2]上海市特种铸造工程技术研究中心,上海201605 [3]上海电机学院材料学院,上海201306

出　　处：《硅酸盐学报》2022年第12期3314-3322,共9页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金面上项目(52104305);上海市2021年度“科技创新行动计划”科技支撑碳达峰碳中和专项(21DZ1208900)。

摘　　要：将Ti-46Al-8Nb合金置于BaZrO_(3)/Al_(2)O_(3)复合模壳中,在氩气气氛下,于1650℃分别保温不同时间。通过使用光学显微镜、扫描电子显微镜、X射线衍射仪及电感耦合等离子体发射光谱仪等分析了复合模壳与合金熔体接触后的界面形貌及合金中耐火材料元素的溶解量,研究了模壳与熔体间界面反应。结果表明:分别保温30、60 min和120 min后,模壳面层受熔体侵蚀并持续发生溶解反应,侵蚀层厚度分别为1510、2476μm和3574μm,侵蚀机理符合扩散型溶解机制控制的动力学模型。合金中O、Zr、Y和Si含量及显微硬度均随保温时间增加而增加。凝固后合金表面形成附着层并有新相形成,其物相为Ba Al_(2)O_(4)和Y_(4)Al_(2)O_(9),合金基体生成(Ti,Zr)5(Si,Al)3和Y_(4)Al_(2)O_(9)2种夹杂物,其含量随保温时间增加而增加。Ti-46Al-8Nb alloy was heated to 1650℃in a BaZrO_(3)/Al_(2)O_(3)composite mould at different time.The microstructure and the dissolution of mould after contacting the alloy melt at different time were analyzed by optical microscopy,scanning electron microscopy,X-ray diffraction and inductively coupled plasma emission spectroscopy,respectively.The interfacial reaction between the alloy melt and the mould was investigated.The results show that the dissolution reaction of the mould in the alloy melt results in the different thicknesses of the erosion layer on the inner wall of the mould(i.e.,1510,2476μm and 3574μm)after the alloy is held for 30,60 min and 120 min,respectively.The erosion mechanism of the melt on the mould follows a dynamic model controlled by the diffusion dissolution.The dissolution of mould refractory results in the increase of the contents of O,Zr,Y,and Si elements in the alloy as the holding time increases,further leading to the increase of the microhardness of the alloy.After solidification,an adhesion layer is formed on the alloy surface.Meanwhile,BaAl_(2)O_(4)and Y_(4)Al_(2)O_(9)phases are formed in the erosion layer.Two typical inclusions,i.e.,(Ti,Zr)5(Si,Al)3and Y_(4)Al_(2)O_(9),are formed in the alloy,and their contents increase with the increase of holding time.

关 键 词：钛铝合金 锆酸钡/氧化铝复合模壳 反应机制 夹杂物 

分 类 号：TQ17[化学工程—硅酸盐工业]