SiCp/Al复合材料在Cl-作用下初期腐蚀行为

Study on the initial corrosion behavior of SiCp/Al composites in Cl- containing solution

摘要:

通过室内浸泡模拟实验方法,采用扫描Kelvin探针技术研究了SiCp/Al复合材料在Cl-介质下初期腐蚀行为。结果表明,SiC颗粒与Al基体界面结合处是复合材料在Cl-介质下初期腐蚀的优先发生位置,Cl-和界面相是促进初期腐蚀发展的主要原因。随腐蚀的不断进行,复合材料先形成钝化膜,表面电位先整体正移,后钝化膜破损,表面电位整体负向移动。复合材料初期腐蚀过程表现为其钝化膜形成和逐渐破损的腐蚀特征,腐蚀产物主要为Al(OH)3、Al2O3和AlCl3。

Abstract:

The initial corrosion behavior of SiCp/Al composites in Cl- containing solution was inverstigated by using immersion test and Scanning Kelvin probe (SKP) technique. The results show that the initial corrosion is preferential to occur at the interface between SiC particles and Al matrix of SiCp/Al composites in Cl- containing solution. Cl- and interfacial phase is responsible for the development of initial corrosion. The passive film formed in the initial stage, while the surface potential of SiCp/Al composites moved positively. When the corrosion process continued, the passive film finally breakdowned, resulting in the negative shift of the surface potential. The main corrosion products are Al(OH)3, Al2O3 and AlCl3.