MAC原位蜕变MC-(Ni-A)复相增强Ni基复合材料及其协同强化机制

For the performance requirements of high strength and ductility, high temperature resistance, corrosion resistance etc. in Ni based materials application in aircraft industry, this project explores a fabrication method of MCx ceramics (such as TiCx, ZrCx etc.) based on MAC in situ phase transformation, and Ni-A intermetallic compounds (such as Ni3Al and NiAl) reinforced Ni composites. The main research contents and the feature of this project consist in that, based on the nano-layered crystal structure of MAC ceramic materials, the characteristics of the A-site atoms can easily escape under the conditions of high temperature and the external force, in situ preparing MCx and Ni-A complex reinforced Ni based composites by using MAC phases as precursor. The key scientific problems include the phase transition of MAC phase caused by reaction, the thermodynamic and kinetic mechanism, the interfacial reaction behavior, the formation mechanism and morphology of MCx ceramic and Ni-A intermetallic compound. The synergistic strengthening effect of MCx phase and Ni-A phase at room temperature and high temperature is studied. The organizational regulation strategy is proposed, and the related preparation methods and processes are optimized. The aim of this project is to reveal the morphology and microstructure evolution of the MCx and Ni-A phase based on MAC in situ phase transformation; reveal the synergistic strengthening mechanism of MCx and Ni-A complex reinforced Ni composites; and provide reference and scientific inspiration for its application in advanced aircraft engines and the improvement in the targeted performance.

针对Ni基材料在航空工业应用中高强韧、耐高温、耐腐蚀等性能需求，本项目探索一种基于MAC相原位蜕变的C缺位MCx陶瓷（TiCx、ZrCx等）、Ni-A（Ni3Al、NiAl等）高温金属间化合物复相增强Ni基复合材料。主要研究内容和特色是利用MAC陶瓷特有的纳米层状结构、高温及外力条件下A位原子容易逃逸的特性，通过对反应引起的MAC相的原位蜕变机制、界面反应行为、MCx基团形成和Ni-A析出动力学机制及组织调控等关键科学问题的研究，以MAC相为前驱体原位制备MCx陶瓷和Ni-A复相强化Ni基复合材料；研究MCx相与Ni-A相在常温和高温下的协同强化效应，提出组织调控策略，并优化相关制备方法及工艺。本项目旨在揭示MAC原位蜕变的MCx相和Ni-A相的形态、组织演变规律；揭示MCx相和Ni-A相对Ni基复合材料的协同强化机制；为其在先进航空发动机等方面的应用和针对性的性能改善提供借鉴和科学启发。

本项目针对Ni基高温合金材料在先进航空发动机等应用中高强韧、耐高温、耐腐蚀和抗烧蚀等性能需求，研制一种基于MAC相的超细MCx陶瓷（如TiCx、CrCx等）为形核剂和增强体、Ni-A（如Ni3Al、NiAl等）金属间化合物为增强相复合强化的Ni基复合材料。主要通过对反应引起的 MAC相的相变及热力学和动力学机制、界面反应行为、MCx相和Ni-A金属间化合物相的生成机制、组织形态等，MCx相对Ni基体的形核细化机理及材料高温特性、变形机理及有效控制MCx相、Ni-A金属间化合物增强相的组分、分布及晶粒大小等关键科学技术问题的研究，研究MCx陶瓷和Ni-A金属间化合物双相协同强化机理及对应的显微组织调控策略，并通过细化效果及常温、高温力学性能的验证，优化相关制备方法及工艺，使该Ni基复合材料具有优异的特性。.通过本项目的研究，1）获得2种及以上具有高强韧、耐高温的超细MCx陶瓷(TiCx、CrCx等)、Ni3Al金属间化合物复相增强Ni基复合材料；2）揭示与Ni反应引起的MAC相（Ti3AlC2、Ti2AlC、Cr2AlC）材料的相变、MCx相和Ni-A相的形态、组织演变及热力学和动力学机制；3）揭示MCx相、Ni3Al相复相增强Ni基复合材料的高温力学特性、协同强化机理及显微组织调控策略。.这些研究工作将为MAX原位转变MCx-Ni3Al增强Ni基复合材料在先进航空发动机等高温构件的制备和使用提供基础材料；为其他高强韧超细晶金属及金属基复合材料的制备提供科学启发作用；为 MAC材料与其他相关材料的反应复合研究产生科学启示。部分研究进展和成果已发表论文19篇，参加国内国际学术会议13人次，申报发明专利已授权7项，培养博士生6名，硕士生14名。