Influences of Sealing Process upon Corrosion Resistance of Anodic Oxidation Film on AI Alloy

在得出铝合金硼酸-硫酸阳极氧化膜、硝酸铈-高锰酸钾封闭工艺配方的基础上,微小变动封闭液中高锰酸钾的含量,通过封闭前后试样的质量变化、点滴试验、无硝酸预浸的磷-铬酸质量损失试验评定出高锰酸钾的最佳含量.分析了氧化膜封闭前后的表面形貌、探讨了氧化膜封闭后的耐腐蚀性能.结果表明,氧化膜经过稀土封闭后表面生成一层均匀、致密的钝化膜,使试样的耐腐蚀性能得到了提高.     

纳米陶瓷铝合金硼酸-硫酸阳极氧化工艺性能的研究

本次通过硼酸-硫酸阳极氧化工艺在纳米陶瓷铝合金表面制备氧化膜层,结果表明：经过硼酸-硫酸阳极氧化后,纳米陶瓷铝合金基体表面形成了一层连续且耐蚀的氧化膜,厚度1.51μm,氧化膜层经过336 h的盐雾试验后,腐蚀点点数小于5个,阳极氧化后表面亲水性变好,氧化膜层与水性底漆具有良好的结合力,油漆附着力测试达到合格。     

封闭工艺对铝合金阳极氧化膜耐蚀性的影响

在得出铝合金硼酸-硫酸阳极氧化膜、硝酸铈-高锰酸钾封闭工艺配方的基础上,微小变动封闭液中高锰酸钾的含量,通过封闭前后试样的质量变化、点滴试验、无硝酸预浸的磷-铬酸质量损失试验评定出高锰酸钾的最佳含量。分析了氧化膜封闭前后的表面形貌、探讨了氧化膜封闭后的耐腐蚀性能。结果表明,氧化膜经过稀土封闭后表面生成一层均匀、致密的钝化膜,使试样的耐腐蚀性能得到了提高。     

第十三次 电镀基础常识智力测验

请迅速回答下列问题(填空) 〔1〕通常经铬酸阳极化的铝氧化膜层很薄,只有__微米,而经硫酸阳极化的铝氧化膜层一般可达__微米。〔2〕铝的硫酸阳极化溶液中主要有害杂质是__离子、__离子和过量的__离子。〔3〕当氯离子含量超过__g/l以后,硫酸阳极化后的铝氧化膜层,就可能产生大量的__腐蚀斑点。〔4〕硫酸阳极化时,温度过高,氧化膜生成速度将__,而溶解速度__,所生成的膜层疏松、有粉末。〔5〕铝及铝合金铬酸阳极化溶液中的有害杂质主要是__和__离子。〔6〕铬酸阳极化溶液中的__价铬含量也不能太高,否则,氧化膜层发__。     

硫硼酸阳极化工艺研究

从原理上分析了铝及铝合金硫硼酸阳极化的机理，对阳极化过程进行相关探索，该工艺氧化膜耐蚀性比硫酸阳极化、铬酸阳极化好，同时还具有对环境污染小，节约能源等优点。     

飞机铝合金零件阳极氧化处理的清洁生产工艺改进

飞机铝合金零件表面处理一直以铬酸阳极氧化处理为代表。我公司引进波音公司的硫酸-硼酸阳极氧化生产线,减轻对环境的污染,实现清洁生产。本文分析我公司铝合金铬酸阳极氧化生产线存在的问题,并在此基础上进行改造,以达到既提高飞机铝合金阳极氧化膜的要求,又减轻对环境的污染的目标。     

铝合金硼酸-硫酸阳极氧化工艺研究

硼酸－硫酸阳极氧化是取代铬酸阳极氧化的一种薄层阳极氧化新工艺。该工艺在环保上属“清洁工艺”。研究了槽液成分,工艺条件及膜层性能。槽液成分中影响膜层重量的主要是硫酸含量,而硼酸可能主要是影响膜层结构。溶液温度和工作电压的影响都是通过对电流密度的影响而起作用,可用控制电量的方法来控制膜层的厚度。     

铝及铝合金的铬酸阳极化

铝合金铬酸氧化膜层不透明,颜色由灰白色到深灰色或彩虹色,比硫酸氧化膜和草酸氧化膜要薄得多,一般厚度只有1~5μm,能保持原来零件的精度和表面粗糙度;膜层质软、弹性高,基本上不降低原材料的疲劳强度;同时,铬酸氧化膜与有机物的结合力良好,是油漆的良好底层,因此,飞机上的结构件很多都需要铬酸阳极化处理。本文介绍了铝合金铬酸阳极化的前处理、上挂、脱脂、清洗、脱氧、阳极氧化、封闭等工艺流程,对每个工序的常用的处理方式加以分析比较,从而找出最佳阳极化处理工艺流程。     

国内外非铬航空涂层的研究进展

综合分析了国内外非铬航空涂层的发展现状;对硼硫酸阳极氧化膜、非铬底漆的防腐性能进行了研究;对硼硫酸阳极氧化对铝合金疲劳性能的影响进行了测试。试验结果表明:非铬涂层需配以含铬的转化涂层才能够满足防腐性能的要求。硼硫酸阳极氧化对铝合金疲劳性的影响与铬酸阳极氧化相当。     

铝合金局部厚膜硬质阳极化工艺

针对有些零件在硫酸或铬酸阳极化后需进行局部厚膜硬质阳极化,提出了以硫酸或铬酸阳极氧化膜经醋酸镍封闭和重铬酸钾封闭后用作局部厚膜硬质阳极氧化保护膜的工艺方法。介绍了其工艺流程,讨论了2种工艺中电压的限制。结果表明,以经醋酸镍和重铬酸钾封闭后的硫酸或铬酸阳极氧化膜作局部厚膜硬质阳极氧化的保护膜,则硬质阳极化时电压分别限制在39 V和42 V。2种工艺得到的硬质阳极氧化膜厚可达到60μm,而且硬质阳极氧化后硫酸或铬酸阳极氧化膜层能通过336 h的盐雾试验。因此,经醋酸镍和重铬酸钾双重封闭后的硫酸或铬酸阳极氧化膜可以取代传统的蜡封或涂漆工艺,用作局部厚膜硬质阳极氧化的保护膜。     

Galvanostatic anodization of pure Al in some aqueous acid solutions Part I: Growth kinetics, composition and morphological structure of porous and barrier-type anodic alumina films

The growth kinetics of anodic films formed on the surface of high purity Al by anodization under galvanostatic conditions at current densities in the range 5–75 mA cm^–2 in thermostatically controlled and vigorously stirred solutions of chromic, sulfuric, phosphoric, citric, tartaric and oxalic acids at different temperatures, were studied. It has been shown that chromic acid solution produces a typical barrier type oxide growth at any given temperature, while the specific kinetic curve representing the combined barrier/porous type film growth is observed when the anodization process is carried out in a nonstirred chromic acid solution. The oxide growth in the rest of the anodizing solutions occurs in different ways depending on the bath temperature. Barrier oxide growth is observed at temperatures lower than 30 °C. Above this temperature, combined barrier/porous oxide growth is observed. In all cases, the slope of the linear part of the potential against time curves, and therefore the rate of barrier oxide growth, increases with increasing anodizing current density and acid concentration, while it decreases with increase in temperature. The composition and surface morphology of the anodic films have been studied by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and atomic force microscopy (AFM).     

铸铝合金硫酸阳极氧化

研究了铸铝合金的表面预处理和阳极氧化工艺;讨论了铸铝合金的表面预处理和工艺条件对阳极氧化膜耐蚀性与厚度的影响;获得了合适的表面预处理方法和阳极氧化工艺条件。     

铝合金阳极氧化废酸的再生

介绍了铝合金阳极氧化的工艺流程及其污染物的来源.采用离子膜分离技术处理阳极氧化废酸,研究了废酸的初始质量浓度和流量对硫酸回收率和铝离子去除率的影响.当废酸中硫酸的初始质量浓度为160 g/L、废酸流量为1.5 m3/h时,硫酸回收率可达到90.62％,铝去除率达到96.78％,回收所得硫酸可用于配制阳极氧化溶液.     

Bonding properties between nitrile–butadiene rubber and aluminum alloy treated by anodizing methods

In this work, the bonding properties between the LD7 aluminum alloy anodized by sulfuric acid or phosphoric acid and nitrile–butadiene rubber (NBR) were investigated. The bonding properties between the anodized aluminum alloys and NBR were compared with those between aluminum alloys treated by burnishing or sandblasting and NBR. The results revealed that, in comparison with sulfuric acid anodized samples, samples anodized in phosphoric acid solutions showed higher 90° peel strength. Under the same conditions, an increase in the anodic film thickness in the studied range may improve the adhesion property between rubber and an aluminum alloy. In comparison with aluminum alloys treated by burnishing or sandblasting, the surface of the anodized aluminum alloy showed homogeneously dispersed pores, which resulted in better and homogeneous bonding properties. A vacuum‐drying process on the anodized aluminum alloys after they were coated with adhesives facilitated penetration of the adhesive molecules into the pores on the oxide layer, which considerably improved the bonding properties. In addition, rubber macromolecules could also penetrate the pores in the aluminum oxide layer, leading to a strong physical anchor–hold interaction after a long time of soaking and diffusion. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

不同电解质制备多孔阳极化Al2O3的形貌与间接诱导形成钙磷涂层能力

利用在Na3PO4液中的直流恒压阳极氧化法和H3PO4液中的恒流阳极氧化法对纯铝片进行阳极化处理。用扫描电子显微镜观察经阳极氧化样品的形貌结构,电子能谱测定诱导生成钙磷涂层的元素构成。结果表明：Na3PO4电解液中阳极化铝片发生过氧化行为形成过氧化膜;以稀H3PO4为电解液制得了孔径可达120～150nm的规整多孔阳极氧化铝(anodic aluminum oxide,AAO)膜。经多步预处理后．再在模拟体液中浸渍2．5d,过氧化AAO膜比规整多孔AAO膜显示出更为优异的诱导生成钙磷陶瓷涂层的能力。     

挤压铸造5035 铝镁合金阳极氧化染黑色后白点故障分析

挤压铸造5035铝镁合金在硫酸阳极氧化以及在酸性染色溶液染黑色后表面出现白点,影响产品的外观。采用能谱仪分析了5035铝镁合金基体及阳极氧化膜的元素成分,并采用金相显微镜观察基体表面形貌及阳极氧化膜的表面与截面形貌,结合基材的挤压铸造过程进行分析,得出产生白点的可能原因是挤压铸造时产生的缩孔。提出了挤压铸造及阳极氧化工艺的改进措施。     

FT-IR Characterization of the Surface of Aluminum as a Result of Chemical Treatment

FT-IR was used to characterize the surfaces of Al after various chemical treatments. All of the oxide surfaces were composed of an anhydrous alumina, aluminum oxyhydroxide (pseudoboehmite) and aluminum hydroxide (close to Gibbsite). The major contaminants in the different oxides are chemisorbed CO₂, carbonates and bi-carbonates. The chromic acid anodized surfaces (CAA) contain more hydroxyls and water than the sulfuric acid anodized surfaces (SAA) while the latter contain more alumina (Al₂O₃). The CAA surfaces have a duplex structure mainly of hydrated and oxyhydroxylated layers over a hydrated alumina layer. The SAA surfaces have a triplex structure composed mainly of hydrated and hydroxylated layers over an oxyhydroxylated layer which is over a hydrated alumina layer. The surfaces chemically converted by the Iridite^© process are composed of a duplex structure of a mixed organic-inorganicl layer over a hydrated alumina. The organic portion of the layer was identified as a carbamate species.     

FT-IR Characterization of the Surface of Aluminum as a Result of Chemical Treatment

FT-IR was used to characterize the surfaces of Al after various chemical treatments. All of the oxide surfaces were composed of an anhydrous alumina, aluminum oxyhydroxide (pseudoboehmite) and aluminum hydroxide (close to Gibbsite). The major contaminants in the different oxides are chemisorbed CO₂, carbonates and bi-carbonates. The chromic acid anodized surfaces (CAA) contain more hydroxyls and water than the sulfuric acid anodized surfaces (SAA) while the latter contain more alumina (Al₂O₃). The CAA surfaces have a duplex structure mainly of hydrated and oxyhydroxylated layers over a hydrated alumina layer. The SAA surfaces have a triplex structure composed mainly of hydrated and hydroxylated layers over an oxyhydroxylated layer which is over a hydrated alumina layer. The surfaces chemically converted by the Iridite^© process are composed of a duplex structure of a mixed organic-inorganicl layer over a hydrated alumina. The organic portion of the layer was identified as a carbamate species.     

电压对7N01铝合金阳极氧化膜结构及耐蚀性的影响

采用160 g/L硫酸溶液在17°C下对7N01铝合金阳极氧化30 min,氧化电压分别选取14、15、16、17和18 V。用扫描电镜观察所得阳极氧化膜的形貌,用能谱仪和电化学测量分析了它的成分、厚度和耐蚀性。结果表明,7N01铝合金经过不同电压下的阳极氧化处理后,表面均能形成凹凸不平并有孔洞的阳极氧化膜,电压为17 V时所制膜层致密、均匀,厚度约为7.6μm,耐蚀性最佳,在3.5%NaCl溶液中浸泡1440 h后没有明显的腐蚀。     

Synthesis and Study of a Polypyrrole–Aluminum Oxide Nanocomposite Film on an Aluminum Surface

Using the method of electrochemical anodization, aluminum oxide porous films are obtained in a sulfuric acid solution. The morphology of the aluminum oxide surface is studied by the method of scanning electron microscopy. The high-quality elemental analysis of the initial and oxidized Al films is performed using the method of electron microprobe analysis. A protective composite polypyrrole-aluminum oxide film is produced on the aluminum surface on top of a porous aluminum oxide film in the galvanostatic oxidation mode by the electrochemical synthesis method. The properties of the polypyrrole–aluminum oxide composite film are studied by the methods of voltammetry, as well as impedance and FTIR spectroscopy.