TiAl合金结构、组织、性能与应用  

Structures,microstructures,properties,and applications of TiAl alloys

作　　者：王子特 郑功[1] 祁志祥[1] 陈旸 许昊[1] 相恒高 陈光[1] Zite Wang;Gong Zheng;Zhixiang Qi;Yang Chen;Hao Xu;Henggao Xiang;Guang Chen(Engineering Research Center of Materials Behavior and Design,Ministry of Education,MIIT Key Laboratory of Advanced Metallic and Intermetallic Materials Technology,National Key Laboratory of Advanced Casting Technologies,Nanjing University of Science&Technology,Nanjing 210094,China)

机构地区：[1]南京理工大学高端装备铸造技术全国重点实验室,先进金属与金属间化合物材料技术工业和信息化部重点实验室,材料评价与设计教育部工程研究中心,南京210094

出　　处：《科学通报》2023年第25期3259-3274,共16页Chinese Science Bulletin

基　　金：国家自然科学基金(92163215,52174364,52101143,51731006,12202201,52201125)资助。

摘　　要：航空航天武器装备轻量化是国家重大战略亟需,但传统金属材料的熔点与密度呈正相关,因此轻质与耐热难以兼得.20世纪中叶发现的TiAl金属间化合物,理论密度只有3.9 g/cm3,不到Ni基高温合金的1/2,且熔点更高,兼具轻质与耐热的优异性能,是制造航空航天及武器装备热端部件的理想材料.本文首先总结TiAl合金相图的发展,简述TiAl合金中不同相的晶体结构与形成机制.其次,介绍TiAl合金可形成的4种典型组织与调控方法,重点探讨不同方法制备的TiAl合金组织特征、力学性能、组织调控及其在航空航天、汽车领域的应用现状.在此基础上,本文展望了TiAl合金的未来发展方向与应用前景.Lightweight aerospace weapons and equipment are a major strategic need for China.Weight reduction of key components of aero engines can improve the thrust-to-weight ratio and reduce energy consumption while also lowering costs and bringing direct economic benefits.Currently,the core hot-end components of aero engines primarily comprise nickel-based superalloys with high density,which restricts technological innovation and progress in the aerospace field to a certain extent.Thus,the development of novel,lightweight structural materials is critical.With a theoretical density of only 3.9 g/cm3,which is less than half that of nickel-based superalloys,and a higher melting point,TiAl intermetallic compounds have attracted considerable attention for aerospace applications owing to their excellent lightweight and heatresistant properties.First,this review briefly describes the crystal structures of the main phases and phase diagrams of TiAl alloys.TiAl alloys comprise two basic phases:γ-TiAl with an L10-type ordered face-centered tetragonal structure andα2-Ti3Al with a D019-type ordered close-packed hexagonal structure.With increasing temperature,the disordered closepacked hexagonalα-phase continues to undergo a phase transformation into the disordered body-centered cubic structureβ-phase.By adding a certain amount ofβ-phase stabilizing elements to the TiAl alloy,the high-temperatureβ-phase can be retained until 25°C,but its crystal structure will transform from disordered to ordered body-centered cubic structureβo phase.Further,the shear of theβo phase along the<111>direction yields the orderedωphase of the hexagonal structure.Another common precipitated phase in TiAl alloys is the Ti2AlNb phase,which has an ordered orthorhombic structure(also known as the O phase)and is mainly produced from theα2 phase.In addition,phase diagrams of high Nb-TiAl and TNM alloys are shown as sample examples.Furthermore,this review focuses on the microstructures and properties of several TiAl alloys.The four typical microstructu

关 键 词：TIAL合金 晶体结构 组织 性能 

分 类 号：TG146.23[一般工业技术—材料科学与工程] V252[金属学及工艺—金属材料]