强磁场织构化高强韧、抗辐照纳米层状类贝壳仿生结构陶瓷

项目名称： 强磁场织构化高强韧、抗辐照纳米层状类贝壳仿生结构陶瓷

项目编号： No.U1232136

项目类型： 联合基金项目

立项/批准年度： 2013

项目学科： 物理学II

项目作者： 胡春峰

作者单位： 中国科学院宁波材料技术与工程研究所

项目金额： 60万元

中文摘要： 纳米层状仿生结构设计是有效提高陶瓷力学性能和调节物理性能的可靠途径。针对传统陶瓷脆性较大的难题，本项目创新性地采用强磁场技术对具有纳米层状结构的六方MAX相陶瓷晶粒进行定向排列设计，从晶粒尺度上对陶瓷结构进行可控精修。其原理依赖于晶粒各向异性的磁感应系数。在强磁场诱导的弱力扭矩下，陶瓷晶粒悬浮于稳定浆料中可发生转动，最终可制备出所有晶粒的c轴均垂直向上的高度织构化陶瓷坯体。经后继电火花离子高温烧结致密化，织构化陶瓷晶粒沿a（b）轴方向择优生长成六方板状形态，构造出c轴统一垂直向上的层状类贝壳叠层结构。该结构具有从纳米尺度到毫米尺度的层片排列特征。织构化陶瓷具有各向异性的物理和力学性能，尤其能极大地提高弯曲强度和断裂韧性，研究将探究其独特的强韧化机制。同时，采用高能氦离子辐照技术研究陶瓷在不同织构化方向上的抗辐照损伤阻力，将系统探索氦泡在纳米层间的形核与长大，建立辐照损伤演化物理模型。

中文关键词： 强磁场；织构化；仿生设计；性能；辐照阻力

英文摘要： The configuration of nanolaminar bionic microstructure is one effective way to enhance the mechanical properties and modify the physical properties of ceramics. Focusing on solving the intrinsic brittleness of traditional ceramics, present project innovatively introduces the strong magnetic field alignment (SMFA) method to align hexagonal nanolayered MAX phases'' grains directionally. At the grain scale level, the microstructure of MAX phases ceramic can be controllablely tailored. The mechanism is ascribed to the anisotropic susceptibility of unit cell of MAX phases. In the strong magnetic field, the ceramic grains in the stable suspension will rotate under the weak torque in order to minimize the system energy. That is, all of the c-axes of grains tend to become parallel to the direction of magnetic field. Finally, the highly textured green bodies can be successfully fabricated with the c-axes of grains perpendicular to the horizontal. Through spark plasma sintering (SPS), dense tailored ceramic can be obtained. During sintering, the grains prefer to grow along a- (b-) axes to form the hexagonal plate-like shape. Therefore, the laminar shell-like nappe with the c-axes of grains perpendicular to the horizontal can be constructed. This kind of microstructure possesses the special characteristic of nanolaminar al

英文关键词： Strong magnetic field；Texture；Bionic design；Property；Irradiation resistance