摘要
碳化硅颗粒增强7A04(SiCp/7A04)铝基复合材料的应用环境及其腐蚀状况都较复杂。过去,对它的研究方法多样,依据不同,因而其腐蚀结论有异,甚至矛盾。为了研究SiCp/Al复合材料的耐蚀性,用电化学法和失重法研究了SiC颗粒含量和粒度对SiCp/7A04铝基复合材料及基体合金耐腐蚀性能的影响。结果表明,与基体合金相比,SiCp/7A04铝基复合材料耐蚀性下降,SiC含量高的复合材料腐蚀较快,SiC颗粒尺寸越大,复合材料耐蚀性越好;采用扫描电镜(SEM)观察腐蚀后的微观形貌表明,SiC颗粒破坏了基体表面氧化膜的完整性,促进了点蚀的形成,但其自身的稳定性又阻碍了蚀孔的长大。
The influence of mass fraction and size of SiC particulates on the corrosion behavior of SiCp/7A04 aluminum matrix compos-ites was studied by using electrochemical methods and immersion tests.The morphologyies of the pitted composites were investiga-ted by means of scanning electron microscopy.Results show that the Al-matrix composites have poorer corrosion resistance than the Al matrix.The composites with a higher content of SiC expe-rienced faster corrosion,and the corrosion resistance increased with increasing size of SiC particulates.This might be because SiC particulates led to damage to the integrity of the oxidation film on and promoted pitting.However,SiC particulates with good thermal stability were able to retard the growth of pitted holes.
出处
《材料保护》
CAS
CSCD
北大核心
2009年第9期24-26,共3页
Materials Protection
基金
上海市科委重点攻关项目(075211012)
关键词
腐蚀
铝基复合材料
SIC颗粒
极化曲线
corrosion behavior
aluminum matrix composite
SiC particulate
polarization curves
