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现在,正在不断开发的碳—铝化系复合材料,具有质轻、高比强度、高弹性模量等优异的力学性能,因此炭纤维增强铝(CF/Al)复合材料可望作为结构材料;由于具有自润滑性和抗震性,因而石墨颗粒分散铝(GP/Al)复合材料可望作为功能材料。这些复合材料的制造和性能存在的问题是:炭材料与铝之间的浸润性不好,在高温下复合材料会发生界面反应等。浸润性不好不仅使成型(复合)困难,而且由于不同相之间的粘结性不好,界面中的应力传递不能充分地进行,因而在强度等力学性能方面未能产生复合的效果,使复合毫无意义。而且在高温下的反应,会在界面生成脆性的Al_4C_3相,使炭纤维的强度降低,因而使CF/Al复合材料的强度显著地下降。由于Al_4C_3在大气中会潮解,界面的粘结力显著减弱,在严重的情况下,连复合材料的形状也不能维持。因此,炭与铝之间的表面改性,是CF/Al复合材料开发中的一个重要的课题。界面改性的方法大致可区分为:(1)铝基添加合金元
At present, carbon-aluminum composite materials under development have excellent mechanical properties such as light weight, high specific strength and high elastic modulus, so CF / Al composites are expected to be used as structural materials. Graphite Particle-dispersed aluminum (GP / Al) composite is expected as a functional material because of its self-lubricating and anti-vibration properties. The problems with the manufacturing and performance of these composite materials are: poor infiltration between the carbon material and the aluminum, interfacial reaction of the composite material under high temperature and the like. Poor wettability not only makes it difficult to mold (composite) but also fails to sufficiently perform stress transmission at the interface due to poor cohesion between phases, thereby failing to provide a compound effect in mechanical properties such as strength Compounding makes no sense. Moreover, the reaction at high temperature produces a brittle Al 4 C 3 phase at the interface, which decreases the strength of the carbon fiber and significantly decreases the strength of the CF / Al composite. As Al_4C_3 deliquescence in the atmosphere, the interface significantly reduced the adhesion, in severe cases, even the shape of the composite material can not be maintained. Therefore, the surface modification between carbon and aluminum is an important issue in the development of CF / Al composites. Interface modification methods can be broadly divided into: (1) aluminum-based alloying elements