不同复盐电解液中NaVO_(3)对铝合金微弧氧化热控膜层结构和性能影响的对比研究  

Comparative Study on the Effect of NaVO_(3) on Microstructure and Properties of Thermal Control Coatings by Micro-arc Oxidation on Aluminum Alloys in Different Double Salt Electrolytes

作　　者：安晓丽 马颖[1] 欧凯奇 李正强 赵琴琴 王乐乐 衡志丹 王晟[1] AN Xiaoi;MA Ying;OU Kaiqi;LI Zhengqiang;ZHAO Qinqin;WANG Lee;HENG Zhidan;WANG Sheng(State Key Laboratory of Advanced Processing and Recycing of Nonferrous Metas Lanzhou University of Technology,Lanzhou 730050,China)

机构地区：[1]兰州理工大学省部共建有色金属先进加工与再利用国家重点实验室,兰州730050

出　　处：《表面技术》2024年第16期103-115,共13页Surface Technology

基　　金：甘肃省创新研究群体计划(1111RJDA011)。

摘　　要：目的在以Na_(2)SiO_(3)为主导的Na_(2)SiO_(3)-Na_(3)PO_(4)复盐电解液和以Na_(3)PO_(4)为主导的Na_(3)PO_(4)-Na_(2)SiO_(3)复盐电解液中加入相同浓度梯度的NaVO_(3),研究着色盐NaVO_(3)对微弧氧化膜层结构的影响,分析膜层的黑度、热控性能、耐蚀性和结合力的变化。方法在A356铝合金表面制备微弧氧化膜层,采用比例分割分批法设计试验。利用ColorReader、涡流测厚仪、SEM、EPMA、EDS、LSCM、XRD、辐射计、太阳光谱反射计,分别表征膜层的颜色、厚度、微观形貌、元素分布、表面粗糙度、物相组成、发射率和吸收率。采用电化学、点滴及盐雾等实验检测膜层耐蚀性,采用热震实验检测结合力。结果在2种复盐电解液中,当NaVO_(3)的质量浓度均为12.06 g/L时,所得膜层颜色最深,且Na_(3)PO_(4)主盐系的颜色更深,其黑度值可低至20.31;热控性能最佳,吸收率和发射率分别高达0.934、0.888;加入着色盐NaVO_(3)后,微弧氧化膜表面出现了自封孔现象,对提高膜层耐蚀性很有利,Na_(3)PO_(4)主盐系膜层的耐蚀性优于Na_(2)SiO_(3)主盐系的,而且也是当NaVO_(3)的质量浓度为12.06 g/L时,膜层的耐蚀性最好;此时,Na_(3)PO_(4)主盐系膜层抗热冲击的次数可高达65。结论在2种复盐电解液中加入着色盐NaVO_(3)后,沉积出了使膜层显深色的钒氧化物。当NaVO_(3)的质量浓度为12.06 g/L时,在各自体系中均可获得同时具有优良耐蚀性、良好结合力、高吸收率、高发射率的热控膜层,且Na_(3)PO_(4)主盐系膜层的性能略高一筹。The work aims to employ two types of double salt electrolytes consisting of Na_(2)SiO_(3)-Na_(3)PO_(4) and Na_(3)PO_(4)-Na_(2)SiO_(3) dominated by Na_(2)SiO_(3) and Na_(3)PO_(4),respectively,with a consistent concentration gradient of NaVO_(3) to fabricate the micro-arc oxidation coatings on the surface of A356 aluminum alloy substrates and investigate the effect of the coloring salt NaVO_(3) on the microstructure of the micro-arc oxidation coatings.Comparisons were made regarding the alterations in blackness,thermal control property,corrosion resistance,and adhesion strength of the coatings,and the merits and drawbacks of the micro-arc oxidation coatings derived from the two types of double salt electrolytes were assessed.The experimental design was executed by a proportional division batch method.Color Reader,eddy current thickness meter,scanning electron microscope(SEM),laser scanning confocal microscope(LSCM),electron microprobe(EPMA),energy dispersive spectrometer(EDS),X-ray diffraction(XRD),emissometer,and solar spectrum reflectometer were employed to characterize the color,thickness,surface morphology,cross-sectional morphology,elemental distribution,surface roughness,phase composition,emittance,and absorptance of the coatings.The corrosion resistance of the coatings was evaluated through electrochemical test,spot test,salt spray test.The adhesion strength of the coatings was examined via thermal shock test.The results revealed that,firstly,the newly synthesized vanadium oxide within the micro-arc oxidation coatings played a crucial role in determining the dark color of the coatings following the addition of the coloring salt NaVO_(3) in both double salt electrolytes.The color of the coatings initially intensified,before gradually softening,transitioning from light brown to dark brown and to black,and eventually settling at a light black hue.At a concentration of 12.06 g/L of NaVO_(3),corresponding to the S3 and P3 schemes,the prepared coatings exhibited the darkest color with the blackness value of the S3

关 键 词：铝合金 微弧氧化 黑色膜 Na_(2)SiO_(3) Na_(3)PO_(4) NaVO_(3) 耐蚀性 热控性能 

分 类 号：TG174.4[金属学及工艺—金属表面处理]