摘要
为了改善铝合金材料的耐腐蚀性能,研究了以正硅酸乙酯(TEOS)为主要原料,加入一定量的-氨丙基三乙氧基硅烷(KH550),并引入纳米TiO2进行复合,以冰乙酸为催化剂,采用溶胶-凝胶法在铝合金基体表面形成复合涂层,并利用氟硅烷进行表面修饰。腐蚀电化学测试分析结果表明,纳米TiO2掺杂制备的复合涂层能够明显的提高铝合金基体的防护性能。并考察了纳米TiO2含量对涂层性能的影响,结果表明,在纳米TiO2质量分数为0.04%时制备的涂层性能最佳,相应的试样在3.5%(质量分数)NaCl溶液中的腐蚀电流密度约为5.965×10 9 A/cm2,而同等实验条件下铝合金基体腐蚀电流密度为7.216×10 5 A/cm2,涂层的存在使腐蚀速率降低了4个数量级,说明涂层对铝合金基体具有显著的防护效果,并且利用扫描电镜(SEM)和接触角测试来考察涂层的致密性和憎水性。
To improve the corrosion resistance,nano-TiO2 composite coatings are prepared on the aluminum alloy substrates via the sol-gel process in which tetraethoxysilane（TEOS） is used as precursor,accompanied with-aminopropyltriethoxysilane（KH550） and some nano-TiO 2.HAc is added as catalyst in the sol-gel process to control the limited hydrolysis.Sols are coated on the surface of aluminum alloy substrates by dip-coating technique.Fluoroalkylsilane is used as dressing agent to surface of composite coatings.The results of electrochemical analysis show that the composite coatings with nano-TiO2 can improve the corrosion resistance of aluminium alloy substrates in 3.5%（mass ratio） NaCl solution effectively.When the sol contains 0.04% mass fraction of nanoTiO2,the corrosion current density for coated sample is 5.965×109 A/cm2,which is 4 orders of magnitude lower compared with that for bared sample（7.216×105 A/cm2）.The scanning electron microscopy（SEM） and contact angle are measured to examine the compactness and hydrophobic nature of coatings.
出处
《燕山大学学报》
CAS
2011年第1期57-61,共5页
Journal of Yanshan University
