含碳纳米管有机-无机复合涂层的制备与防护性能  

Preparation and protective effects of carbon nanotube-containing organic-inorganic composite coatings on aluminum alloys

作　　者：李恒[1] 李澄[1] 王加余[1] 

机构地区：[1]南京航空航天大学材料科学与技术学院,南京210016

出　　处：《复合材料学报》2010年第6期38-44,共7页Acta Materiae Compositae Sinica

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KH-550,并引入部分羟基化的多壁碳纳米管(MWCNTs-OH)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。腐蚀电化学测试和扫描电镜分析结果表明,MWCNTs-OH的引入能够明显提高涂层的防护性能,并有效防止涂层开裂。考察了MWCNTs-OH含量和热处理温度对涂层性能的影响。结果表明:MWC-NTs-OH质量分数为0.04%、热处理温度为130℃时制备的涂层性能最佳,相应的试样在3.5 wt%NaCl溶液中的腐蚀电流密度约为3.056×10-8A/cm2,而同等实验条件下铝合金基体腐蚀电流密度为7.216×10-5A/cm2,涂层的存在使腐蚀速率降低了3个数量级,涂层对铝合金基体具有显著的防护效果。To improve the corrosion resistance,（MWCNTs-OH）-containing organic-inorganic coatings were prepared on the aeronautic aluminum alloy substrates via the sol-gel process in which tetraethoxysilane（TEOS）,KH-550 and some hydroxylated multi-walled carbon nanotubes（MWCNTs-OH） were used as precursors.HAc was added as catalyst in the sol-gel process to control the limited hydrolysis.Sols were coated on the surface of aluminum alloy substrates by dip-coating technique and the composite coatings were obtained through necessary heat treatment afterwards.The results of electrochemical analysis show that the composite coatings with nanotubes can effectively improve the corrosion resistance of aluminium alloy substrates in 3.5wt% NaCl solution.When the content of MWCNTs-OH is 0.04wt% and the heat treatment temperature is 130℃,the corrosion current density for coated sample is about 3.056×10-8A/cm2,which is 3 order lower than that for bared sample（7.216×10-5A/cm2）.The SEM morphology of the coatings also reveals that the introduction of MWCNTs-OH to coatings is beneficial to prevent from the coating cracking.

关 键 词：溶胶-凝胶 碳纳米管 电化学测试 耐腐蚀性能 复合涂层 

分 类 号：TG174.4[金属学及工艺—金属表面处理]