多尺度第二相混杂增强铝基复合材料的变形行为与摩擦磨损性能相关性研究

To further improve its high temperature friction and wear performance by improving the rheological behavior of aluminum matrix composites is the key to expand its application in the automotive, aerospace and other fields. It is one of the effective ways to fabricate high-performance aluminum-based composites through hybrid reinforcement of the nano-particle and micro-particle. This project aims at fabricating hybrid reinforced aluminum matrix composites with nano-TiB2 and micro-SiC particles by powder metallurgy method and focuses research on the effect of composition and preparation process parameters on the microstructure evolvement and the rheological behavior of the hybrid reinforced composites. The tribological behavior of hybrid reinforced composites will be systemically studied, and the plastic deformation and microstructure evolvement of worn surface and sub-surface will be analyzed to indicate its wear mechanism. On the basis of the results, the influence law of microstructure on deformation behavior and friction and wear of multi-scale second phase microstructure of hybrid reinforced aluminum matrix composites will be clarified. The influence mechanism of multi-scale second phase particles on the deformation behavior, friction and wear behavior will be revealed. At the same time, the correlation between deformation behavior and the wear mechanism of hybrid reinforced composites will be proved. This project will enrich the friction and wear theory of hybrid reinforced composites and provide necessary theoretical basis for developments of new high-performance aluminum based composites, and pave the way for its engineering application.

通过改善颗粒增强铝基复合材料流变行为从而提高其高温摩擦磨损性能是扩大铝基复合材料在汽车、航空航天等领域应用的关键。利用纳米/微米第二相复合强化效应是制备高耐磨性铝基复合材料的有效途径之一。本项目采用粉末冶金法制备纳米TiB2/微米SiC颗粒混杂增强铝基复合材料，开展材料组成、制备工艺对材料组织影响规律的研究，揭示混杂复合材料的流变行为与特征，系统研究混杂增强铝基复合材料的摩擦磨损性能及其机制。在此基础上探明多尺度第二相混杂增强铝基复合材料的微观组织对材料变形行为、摩擦磨损行为的影响规律，揭示不同尺寸第二相颗粒影响流变行为、磨损性能的机制，明确混杂复合材料变形行为与磨损机制之间的相关性，本项目的开展将丰富混杂增强复合材料摩擦磨损理论，为开发高耐磨性铝基复合材料提供理论支撑，并为其工程化应用奠定基础。

随着汽车、交通运输、航空航天等领域对铝基复合材料力学及摩擦磨损性能的要求越来越高，单一增强相增强铝基复合越来越难以满足性能要求。对铝基复合材料来说，在通过优化基体合金成分来改善材料性能程度有限的条件下，改变传统复合材料单一增强相配置模式，从调控增强相尺寸配比的角度出发， 实现尺度上微米和纳米双增强相混杂增强，利用其协同增强效应，从而进一步发掘材料的性能潜力、实现综合性能指标的最优化配置，是铝基复合材料发展新方向。.本项目通过重点研究：（1）粉末冶金法制备SiCp/TiB2颗粒混杂增强铝基复合材料；（2）SiCp/TiB2混杂增强铝基复合材料的微观组织及力学性能；（3）SiCp/TiB2混杂增强铝基复合材料的摩擦磨损行为研究；（4）RGO/SiCp混杂增强铝基复合材料的制备过程、微观组织及力学性能；（5）RGO/SiCp混杂增强铝基复合材料的摩擦磨损行为研究；（6）Al-7Si/(10 wt.%SiCp + 5 wt.%TiB2)混杂增强铝基复合材料高温流变行为研究；（7）TiB2含量对Al-7Si/(10 wt.%SiCp + x TiB2)复合材料高温流变行为的影响。探明了多尺度第二相混杂增强铝基复合材料的组成（第二相颗粒尺寸、相对含量）、微观组织对材料变形行为、摩擦学行为的影响规律，揭示了不同尺寸第二相颗粒影响材料变形行为及磨损性能的机制。本项目的关键技术突破是通过多尺度混杂增强有效提升了铝基复合材料的力学性能、耐磨性能，通过对其机理进行探讨揭示了多尺度增强相对材料的强化机理，并对其变形行为进行了研究，为混杂增强金属基复合材料的工程化技术研究和开发奠定了坚实的理论基础。