SiCp/ Al复合材料与化学镀镍层结合机理研究

根据结构化学理论，用SEM, EDAX和XPS等测试手段研究了镀层和碳化硅颗粒增强铝基复合材料(SiC_p/ Al)的表面、断面形貌及界面的结合状态，分析了镀层和基体之间的结合机理。结果表明，Ni镀层与复合材料界面有良好的结合，在复合材料表面的SiC-Al界面，初期沉积物Ni按Al的晶格外延生长出现微晶层，然后吸附原子扩散迁移、碰撞结合并与界面上的SiC晶格匹配生长，在镍层中诱发了拉伸应力。镍晶格和基体粒子之间产生了键合作用，形成的键显示出共价键和离子键的混合性质。

Study on Adhesion Mechanism of SiCp/ Al Composites and Electroless Nickel Coating

The morphology of the surface and the cross-section and the interface state of the coatings and aluminum matrix composite reinforced by silicon carbide particles (SiC_p/ Al) were investigated by SEM, EDAX and XPS techniques. Adhesion mechanism between Ni layer and substrate is analyzed. The results show that the coatings and the composites have excellent adhesion. The early Ni deposits tended to occur as microcrystalline layers on the SiC-Al interface due to growth extention according to Al crystal lattice. Then the adsorbed atoms diffused and integrated to matching growth with SiC lattice, which places a premium on the tension stress. This makes it clear that a bonding action has generated between matrix Ni and substrate particles and that Ni atom prefers to obtain electrons during the bonding process. The chemical bonding is formed the between coating and the substrate. The bond shows a mixed property of covalent bond and ionic bond.