日本铝表面处理技术访华团交流座谈专题报导——第二报 铝及铝合金着色技术

日本东京都立工业技术中心主任研究员三田郁夫、日本铝生产技术研究所所长山本崇等人针对建筑、光学仪器、铭牌、日用品等不同对象,介绍了目前在日本取得工业应用的铝阳极氧化自然发色、电解着色(二次交流电解,电流反向电解法)及染色等技术内容,现归纳整理如下(重点介绍反向电解法和有机染料着色). 一自然发色法阳极氧化自然发色有如下两种途径: (一) 用易发色的材料在特殊电解液中进行阳极氧化,此法所得膜层耐光性好,但电解液管理困难(与常用硫酸电解液相比),而且电解液成本高,氧化时需要高电压,高电流密度,色调种类也受到限制,为得到各种色调需配置各种专用电解槽.基于上述原     

铝及铝合金电解着古铜色工艺试验

铝及铝合金阳极氧化膜电解着色工艺自六十年代问世后,由于其成本低廉、生产效率高、操作简便,可以通过控制着色时间和槽电压,任意地调节氧化膜颜色的深浅,而且设备简单,从而引起了人们的关注。用作装饰、防护的氧化膜电解着色,在目前最为流行的是电解着古铜色和茶色。然而根据近期资料介绍,着色液的稳定性,氧化膜的色泽,色差的控制等方面还存在着一     

科技简讯

铝阳极氧化膜电解着色工艺,具有色膜耐磨、耐晒、耐腐蚀、耐高温、生产成本低、效率高等优点,所以在家用电器、日用五金、建筑材料等铝制品中得到广泛应用。     

在铝或铝合金上形成彩色条纹的方法

铝件的早期电解着色法是在铝的阳极氧化膜上均匀地着色(单色),一般是把预先阳极氧化后的铝,在含有金属盐或酸的溶液中,用直流(阴极电解),交流或交直重叠电流或具有同等效果的各种波形电流进行电     

镍—锌双盐铝阳极氧化膜电解着色工艺研究

研究了镍一锌双盐铝阳极氧化膜电解着色工艺。探明了着色液中各组分的作用和电解参数对着色效果的影响，从而得出最佳工艺。对着色液性能进行了测定，结果表明镍一锌双盐体系的分散能力明显优于纯镍盐溶液，与纯亚锡盐电解着色液的分散能力相当。该体系的抗杂质干扰能力明显优于纯镍盐溶液。实验结果表明，在该体系中电解着色铝氧化膜层的耐蚀性、耐磨性及耐外紫光照射性能良好。     

铝阳极氧化电解着色

铝阳极氧化电解着色,1936年就发明了.但很长时间没有引起人们的注意,直到六十年代后期才开始发展,七十年代起欧洲各国和日本广泛用于生产.我国近几年才研试应用. 铝阳极氧化膜电解着色的原理是,首先用阳极氧化的方法使铝表面生成一层8～10微米厚的氧化膜,然后在金属盐溶液中,通过交流电处理,使金属微粒沉积在氧化膜空隙底部.铝阳极氧化膜的颜色由于光线在金属微粒(3～4微米)上的散射而产生.颜色的深浅与金属微粒沉积的数量以及在膜内     

医学外用铝合金多功能涂层的电化学制备

采用4因素3水平的正交实验,确定经阳极氧化铝合金后在其表面进行电解着色铜的最佳工艺,并用TiO2溶胶对着色膜进行封孔处理。采用扫描电镜、能谱仪、X射线衍射仪对涂层的形貌、成分分布、结构等进行表征,研究涂层的耐蚀性、耐擦拭性、亲水性、光催化性、抗菌性等。结果表明,氧化膜为砖红色,厚约40~50μm,主要由非晶态的氧化铝构成,铜纳米粒子和TiO2沉积在孔中。经电化学氧化着色和TiO2封孔后形成了耐蚀、装饰、亲水、光催化、抗菌的多功能涂层,其性能较沸水封孔的涂层有很大提高,可用于医学外用设备。     

阳极化铝光干涉电解着色的研究

用Ｌ２－ＬＤ３１铝材进行了青铜色以外颜色电解着色的研究。通过本文较为系统的工作找到了磷酸扩孔和锡盐着色适宜的条件，获得了除蓝色以外的比较稳定的红、黄、绿色，并且耐磨、耐晒和封闭的质量敢可达到基本合格要求。用磷酸阳极氧化和酸化的Ｎｉ－Ｃｕ着色液或用酸性铜着色液可获得纯正蓝色的干涉色薄膜。     

国外电镀文摘

9101001钛的着色——私市夏。表面技术,1989,40(1):66(日文) 着色的钛与着色的铝和不锈钢相比,具有色彩独特、强度高、耐蚀性好的优点。钛的着色分为化学着色、热氧化着色和电解着色,以电解着色的色调最为丰富。电解着色中最重要的影响因素是氧化电压,基体表面粗糙度的不同也会造成一些不同效果。要保证色泽均匀,前处理十分重要。近年来,钛的着色技术已在日本用于建筑工业。 9101002钛阳极氧化在建筑材料方面的应用——山口英俊。表面技术,1989,40(1):64(日文) 钛阳极氧化着色后,膜层的耐蚀性和防变色性能都远比铝和不锈钢的膜层性能好,日本自1973年以     

镁合金阳极氧化的研究与发展现状

综述了镁合金阳极氧化工艺的研究与发展现状，包括着色和密封技术，阳极氧化涂层的反应机理和结构，以及镁和铝阳极氧化之间的异同点，提出了进一步研究和开发的方向。     

Anodic oxide growth on aluminium surfaces modified by cathodic deposition of Ni and Co

Surface conditions similar to those found in aluminium alloys of practical use were assessed by cathodic deposition of transitions metals (Ni and Co) from different electrolytes. Fundamental aspects concerning with the growth of anodic oxide films at potentials lower than 10 V in neutral acetate buffer solution on these modified surfaces were analysed by common electrochemical techniques complemented with scanning electron microscopy and transmission electron microscopy. In both potentiodynamic and galvanostatic modes, the growth of aluminium oxide competes with the dissolution of deposited metal particles. The formation of a thin aluminium barrier oxide film beneath them shifts the dissolution potential over to 1.5 V towards more positive values. Some particles get progressively embedded in the matrix of the growing alumina and act as cation sources, increasing the film conductivity and diminishing the established electric field in the oxide. This effect is more pronounced with Co deposits due to its high active dissolution rate, before passivation occurs. Then, the generation of a two-layer film is explained in terms of the precipitation of metal hydroxide at the solution side on the oxide barrier film.     

Modification of magnetic properties of metal nanoparticles using nanotemplate approach

We demonstrate a nanotemplate approach by which different metal magnetic nanoparticles (Ni–Co, Ni–Fe and Co–Pt alloy particles) can be fabricated on a polyimide (PI) film. The process relies on the high interfacial energy between deposited metal and the PI film which forces the deposited metal film to preferentially nucleate on the pre-existing Ni seed particles. During subsequent thermal annealing, the deposited metal film coalesced onto the Ni seed particles to form a monolayer of magnetic nanoparticles on the PI film. Furthermore, the deposition/annealing can be repeated to change both size and constituent of the nanoparticles by introducing a different metal film during deposition. Potentially, any metal film can be deposited onto the Ni seed particles provided that the metal does not react with the Ni seed particles to create a monolayer of metal nanoisland structures with desire magnetic properties.     

Corrosion protection and formation mechanism of anodic coating on SiCp/Al metal matrix composite

The corrosion protection from sulfuric acid anodized coatings on 2024 aluminum and SiC particle reinforced 2024 aluminum metal matrix composite (SiC_p/2024Al MMC) in 3.5 wt.% NaCl aqueous solution was investigated using electrochemical methods. The results show that the anodized coating on 2024Al provides good corrosion protection to 3.5 wt.% NaCl, and the anodized coating on the SiC_p/2024Al MMC provides some corrosion protection, but it is not as effective as for 2024Al because non-uniformity in thickness and cavities present are associated with the SiC particulates. Cavities above SiC particles are the reason that the anodized coating on the MMC cannot be completely sealed by hot water as with anodic Al alloy. SiC particle anodizes at a significantly reduced rate compared with the adjacent Al matrix. This gives rise to alumina film encroachment beneath the particle and occlusion of the partly anodized particle in the coating. It was found that the barrier layer of anodized Al MMC is not continuous, and it is composed primarily of the barrier layer of anodized Al matrix and a barrier-type SiO₂ film on occluded SiC particles in the coating. A new formation mechanism of coating growth during anodizing of a SiC_p/2024Al MMC was proposed.     

Anodization of evaporated aluminium on Ti-6 wt% Al-4 wt% V

Evaporated aluminium on Ti-6 wt% Al-4 wt% V alloy was anodized in phosphoric acid and other electrolytes. The anodic oxide formed was characterized by various techniques and it was found that a duplex oxide forms in which titanium has diffused through the aluminium oxide film and appears at the surface and throughout the film.     

Concentration profiles of passive films formed on niobium metal and niobium-base alloys by auger electron spectrometry

Concentration profiles of passive films formed on electrolytically anodized niobium and niobium-base alloys are obtained by Auger Electron Spectroscopy with simultaneous ion beam etching. The alloys investigated include 5Zr-Nb, 3Zr-10Ti-Nb, 2.5Zr-2W-Nb and 1Zr-5Mo-5V-Nb. Experiments demonstrate that AES is among the most fascinating techniques for solving various characterization problems related to the structure and composition of the thin films formed by anodization. Data presented supports evidence that combined anodic and cathodic movements take place during film growth.     

A study of corrosion fatigue behaviour of anodized and unanodized 2024-T3 aluminium alloy

The corrosion fatigue (CF) behaviour, under constant deflection bending conditions with a pulsating tension stress form, of 2024-T3 aluminium alloy, unanodized and anodized to form a thick porous film, in 3.5% NaCl solution has been investigated. It was found that E _corr varies very little until specimen fracture under low frequency CF conditions, whereas E _corr drops rapidly when approaching the later fracturing stage of the CF process under high-frequency conditions for unanodized specimens. However, a slow drop in E _corr was detected from the commencement of the CF process, and lasted up to a much more rapid drop at a later fracturing stage for the anodized specimen. This behaviour presumably can be explained by the cracking of the anodic film and the theory of imperfect recovery of the surface film. It is suggested that the E _corr monitoring technique may be useful for determining the remnant CF life for existing structural parts of this alloy or other aluminium alloys regardless of whether or not they are anodized. Furthermore, the T3 temper provides a microstructure which may retard main-crack formation and penetration in the CF process of the anodized alloy, thus mitigating partly the negative effect of the readily crackable anodic film.     

温度冲击对不同阳极氧化温度SiC_P/2A12复合材料阳极氧化膜开裂行为的影响

通过己二酸-硫酸工艺制备了SiCP/A1合金(2A12)复合材料阳极氧化膜,研究了不同阳极氧化温度下(15~35℃)制备的SiCP/2A12复合材料阳极氧化膜温度冲击后的开裂行为及耐蚀性能。采用FE-SEM对温度冲击前后SiCP/2A12复合材料阳极氧化膜的微观形貌进行了分析,采用电化学阻抗谱(EIS)研究了冲击前后SiCP/2A12复合材料阳极氧化膜的耐腐蚀性能。结果表明:温度冲击对不同阳极氧化温度制备的SiCP/2A12复合材料阳极氧化膜影响程度不同,随着阳极氧化温度的升高,温度冲击后SiCP/2A12复合材料阳极氧化膜的裂纹密度逐渐增加。阳极氧化温度为25℃时,温度冲击后SiCP/2A12复合材料阳极氧化膜耐蚀性最好。SiCP/2A12复合材料阳极氧化膜的耐温度冲击性能优于2A12铝合金氧化膜。     

Diffusionslöten von Aluminium mittels PVD applizierter Lotzusatzwerkstoffe

Diffusion brazing of aluminium by PVD applied filler metals Diffusion brazing of aluminium and aluminium alloys precoated with filler metal components enables fluxless wetting and obtains braze joints of high strength at moderate brazing temperatures. Previously deposited components of filler metals on the base materials as thin film, using Arc‐PVD‐process lead during a subsequently diffusion brazing process to the formation of a local liquid phase (transient liquid phase). The liquid phase is formed from the deposited thin film material and the base material and is solidified isotherm due to diffusion procedures. In doing so braze joints of higher melting point than brazing temperature can be realised. In this work, vacuum brazing of the two systems, Al‐Cu and Al‐Cu‐Si have been investigated. Cu and Al‐Cu‐Si were deposited on the base material using Arc‐PVD‐process. The base materials were pure aluminum and EN‐AW6060. Metallographic and scanning electron microscope analyses proved that the braze seam area after the completed diffusion brazing process shows similar structure and composition as the base material.     

Influence of microstructure on electrograining behaviour of commercial purity aluminiumused for lithographic printing plates

Abstract

High quality lithographic printing plates are made from electrolytically roughened aluminium sheets. A nitric or hydrochloric acid based electrolyte is normally used for the electro graining, and the substrate is most commonly commercial purity (CP) aluminium. Little is known about the relationship between the substrate microstructure and the pitting behaviour during electrograining in nitric acid solutions. The present work used three techniques to study the initiation and growth of surface pits responsible for the surface roughening of CP aluminium. A laboratory microcell simulated commercial graining but with the ability to interrupt the process and to rapidly clean and preserve the partially grained surface. Detailed scanning and transmission electron microscopy has been used to link substrate microstructure to pit initiation and growth morphology. The results demonstrate that the cold worked dislocation structure is an important feature whereas examination of simple binary alloys illustrates the relative roles of solute in solid solution and coarse particles. The present work suggests that the barrier oxide is very important and it has been postulated that chemistry or defect structure modifications to the film control the process of pit site selection.

MST/3137