NiCoMnIn/Mg智能复合材料研究

NiCoMnIn particles reinforced Mg matrix smart composites with good damping property and magnetic driving performance are proposed and investigated in this project by combining the merits of high response frequency, good damping property and large magnetic field-induced strain for NiCoMnIn magnetic shape memory alloy and the advantages of light weight and good damping property for pure Mg. First, the NiCoMnIn bulk alloys with various compositions are prepared, and the martensitic transformation, damping property and magnetic field-induced phase transformation property are investigated. Then, the bulk alloys are crushed and ball milled to be small particles, which are annealed subsequently under vacuum at different temperatures. The effect of microstructure (morphology, particle size and grain size etc.) of the particles on the thermal-induced and magnetic field-induced martensitic transformation performance is studied, based on which the preparation process for making particles with good functional properties is confirmed. The NiCoMnIn particle/Mg composites are prepared using spark plasma sintering technology under protection of Ar atmosphere. The effect of microstructure of the composites on the mechanical property, damping property and magnetic field-induced phase transformaton strain is investigated and then the preparation technology of the composites will be optimized. Finally, the design criteria and preparation technology of NiCoMnIn particle/Mg smart composite with good damping property and magnetic driving performance are confirmed, which will provide experimental references for the development of novel light metal matrix smart composites.

结合磁性记忆合金NiCoMnIn具有高响应频率、高阻尼和大磁诱发应变的优点和金属镁具有轻质和良好阻尼的优点，尝试制备具有高阻尼和磁驱动属性的NiCoMnIn颗粒增强镁基智能复合材料。本项目首先制备不同成分的NiCoMnIn合金块材，研究块材的马氏体相变、阻尼和磁诱发相变性能。然后利用机械球磨的方法将合金块材粉碎成细小的合金颗粒，将球磨后的颗粒进行不同工艺的真空热处理退火，研究颗粒显微组织（颗粒形貌和尺寸、晶粒尺寸等）对热诱发和磁诱发马氏体相变性能的影响，确定具有良好功能特性颗粒的制备工艺。利用放电等离子体烧结的方法制备NiCoMnIn颗粒/镁复合材料，研究复合材料显微组织对复合材料力学性能、阻尼性能和磁诱发相变应变的影响规律，优化复合材料制备工艺，确定具有高阻尼和磁驱动性能NiCoMnIn颗粒/镁智能复合材料的设计准则和制备工艺，为发展新型轻金属基智能复合材料提供实验参考。

近年来，NiCoMnIn等磁性记忆合金由于具有高响应频率、大磁诱发应变、高阻尼和大输出力的优点而得到了广泛研究。但是由于此类合金属于金属间化合物，因此合金的脆性较大，不利于实际工程应用。本项目提出将NiCoMnIn合金球磨成颗粒，然后与镁粉利用放电等离子体烧结的方法进行复合制备NiCoMnIn颗粒/镁智能复合材料，通过镁基体改善合金的力学性能。首先熔炼制备了NiCoMnIn多晶块材，然后将块材球磨成细小的合金颗粒并进行真空退火处理，详细研究了NiCoMnIn块材、颗粒的显微组织、晶体结构和马氏体相变行为。利用放电等离子体烧结的方法将合金颗粒与镁粉烧结制备NiCoMnIn颗粒/镁复合材料。详细研究了复合材料的微观组织、马氏体相变、磁诱发应变、阻尼特性和力学性能。此外，我们还对NiCoMnSn、NiMnGa基合金的块材、颗粒和镁基复合材料的性能进行了研究。详细分析了影响合金块材、颗粒和复合材料马氏体相变行为的主要因素，建立了磁性记忆合金颗粒性能、复合材料显微组织与复合材料力学性能、阻尼特性和磁诱发应变性能之间的联系，阐明了影响复合材料功能特性和力学性能的微观机制。本项目的研究结果可以为新型金属基智能复合材料的设计和开发提供实验参考。项目执行过程中，在磁性记忆合金块材、颗粒以及复合材料的显微组织、马氏体相变以及力学性能研究方面取得了一定的研究成果，共发表学术论文12篇，其中SCI收录11篇。