碳纤维布增强铝基复合材料界面行为的研究

Carbon fiber reinforced aluminium matrix composite is one of the most significant composite materials. Due to its lightweight, high strength, good plastic and thermal conductive properties, it is considered as an ideal functional and structural material, which can be widely used in martial, automotive and aeronautic fields. The interface combination between carbon fibers and aluminium matrix is the most important step during the whole preparation process, as well as the most difficult one to control. In this project, the carbon fiber is reinforced as woven-cloth shaped. It takes the interface behaviour between carbon fiber and aluminium alloy matrix as the investigated object to study the reaction, products and interface morphology by using simulation, in situ image and HRTEM, etc.. A series of studies are performed, including the wettability, the heat transfer and mass transfer law between molten aluminum alloy and carbon cloth under surface treatment, electromagnetic and pressure fields. The influence of those conditions on the formation and evolution law of interface structure will be investigated as well. Then the thermodynamic and kinetic mechanisms of interface reaction during solidification process will be analyzed, as well as the interface deformation mechanism during solid deformation process. On the basis of these researches, the infiltration of aluminum alloy melt into fiber bundle can be solved and the interface reaction between them is controllable, those are beneficial to provide a developed preparation technology of cloth-shape carbon fiber reinforced aluminium matrix composite.

碳纤维增强铝基复合材料是一种重要的复合材料，因具有轻质、高强、良好的塑性和导热性，被认为是理想的功能材料和结构材料，可广泛应用于航天航空、军事和汽车工业等领域。碳纤维与铝基体的界面结合问题是碳纤维增强铝基复合材料制备过程中最重要也是最难控制的环节。本项目以碳纤维布增强铝基复合材料为研究对象，研究碳纤维布与铝基体凝固过程及塑性变形阶段的界面行为。利用同步辐射原位成像、数值模拟、高分辨透射电镜等手段表征凝固过程中碳纤维与铝基体的界面反应、界面形貌及反应产物，研究电磁场、压力场及表面处理对界面行为的影响机制，研究固态变形过程中界面结构的协同变形机制。掌握碳纤维与铝基体结合过程中界面的形成和演变规律，并深入阐释界面形成的热力学和动力学机制。在此基础上，解决铝熔体对碳纤维布的浸渗问题，并实现控制碳纤维与铝基体的结合反应过程，为研究碳纤维增强铝基复合材料的制备方法提供理论指导。

碳纤维增强铝基复合材料因具有轻质、高强、良好的塑性和导热性等特点，被认为是理想的功能材料和结构材料，有望应用于航天航空、军事和汽车工业等领域。本项目以碳纤维编制布增强铝基复合材料为研究对象，研究碳纤维与基体结合过程中的界面反应行为，以及凝固过程中镀层工艺和外场对界面行为的影响，为碳纤维增强铝基复合材料的制备方法提供理论指导。本项目经过三年研究，取得如下结果：.1、提出一种半固态铸轧法制备碳纤维布增强铝基复合材料的工艺，利用压力场促使铝基体和碳纤维编织布的界面结合。借助模拟计算建立了温度参数和塑性变形量间的关系，阐释变形机制。通过调控外加压力和金属流动性，实现了铝熔体对碳纤维布的完全渗进。碳纤维编织布增强铝基复合材料板材能够在弯曲变形中提供良好的强化效果。.2、得到基体和纤维的渗进规律，阐释电磁诱导的渗浸转变机制。在液态复合过程中引入脉冲磁场，实现了金属熔体对编织布的渗浸过程由逐层渗浸方式向梯度同步渗浸方式转变。电磁场引入的磁致压力促进增加熔体渗浸深度。以此为基础实现了电磁铸造法制备碳纤维布增强铝基复合材料。.3、设计针对平纹碳纤维编织布的表面镀层新工艺。在传统化学镀层的工艺基础上，优化了一种针对于平纹碳纤维编织布特点的表面化学镀镍方法，将镀液的稳定时间延长至 120min以上，镀层的含磷量降低至9wt.%。并通过开发新的氧化剂体系，设计了胶态钯镀液化学镀镍工艺和碳纤维表面接枝短链羧酸铜的工艺。不仅简化了原有的镀层工艺，大幅降低了成本，更提升了镀层的均匀性与稳定性。