第二相特征参数与FeWB/Fe屏蔽复合材料力学行为相关性研究

FeWB/Fe composites which using FeWB as functional components, are a kind of new shielding materials with combined structural and functional performance. However, the strength and shielding peroperties are increased, while the ductility and toughness are decreased with the contents of tungsten and boron increasing. In order to obtain the FeWB/Fe shielding composites which have both excellent shielding performance and good mechanical properties, this project intends to prepare FeWB/Fe composites with different FeWB particle size, morphology and distribution by hot isostatic pressing sintering or spark plasma sintering. The influencing rule and mechanism of FeWB particle size, morphology, distribution and the interface between FeWB and Fe on the mechanical properties of FeWB/Fe composites are investigated by SEM, TEM, EDS and so on. The aim is to establish a deep relationship between the second phase characteristic parameters and the mechanical behaviors of FeWB/Fe composites, and seek the ways to improve the mechanical properties. The research has great significance for the preparation and application of FeWB/Fe composites with combined structural and functional performance.

采用FeWB作为功能相可以制备FeWB/Fe复合材料，该材料是一种新型的结构-功能一体化屏蔽复合材料。然而，随着钨、硼元素含量升高，材料的强度和屏蔽性能升高，但其塑、韧性将大幅下降。为获得兼具优异综合屏蔽性能和良好结构力学性能的FeWB/Fe屏蔽复合材料，本项目拟采用热等静压烧结或放电等离子烧结方法，制备不同FeWB颗粒尺寸、形态和分布的高钨硼含量FeWB/Fe屏蔽复合材料，结合SEM、TEM、EDS等方法，研究第二相尺寸、形态、分布及与基体界面关系对复合材料力学性能的影响规律和作用机理，建立第二相特征参数与复合材料力学行为之间的内在关联，寻求改善和提高复合材料综合力学性能的方法和途径。本课题的开展，对新型结构-功能一体化屏蔽复合材料的制备和应用具有重要意义。

本课题从复合材料可设计性角度出发，设计和制备了一种以FeWB为屏蔽功能组元的新型屏蔽复合材料——FeWB/Fe屏蔽复合材料。根据材料微观电子结构与性能之间的关系，以及中子和γ射线与物质的相互作用关系，对FeWB的晶体结构﹑热力学性质和屏蔽性能进行了计算，揭示其稳定性和功能性；采用反应合成的方法制备了第二相FeWB合金粉末；采用热等静压烧结技术，制备不同FeWB颗粒含量、尺寸、形态和分布的量FeWB/Fe屏蔽复合材料，结合X-射线衍射、光学金相、扫描电镜、能谱分析和拉伸试验等测试手段，表征了第二相特征参数对FeWB/Fe屏蔽复合材料微观结构和力学性能的影响，揭示了复合材料强韧化机理；分析了FeWB/Fe界面对复合材料力学性能的影响；同时，采用理论计算和实验测试相结合的方法，表征了FeWB/Fe屏蔽复合材料的热中子和γ射线屏蔽性能。本课题的开展，为开发结构-功能一体化的FeWB/Fe屏蔽复合材料提供了理论及技术基础。课题执行期间，公开发表论文3篇，其中SCI/EI 收录论文2篇，发表GF报告1篇，申请国防/发明专利3项。