Aluminum coatings cladding

Aluminum and aluminum-clad steels am highly resistant to naphthenic acids under most conditions. Aluminum-coated steels give good service until coatings fail at coating imperfections, cracks, welds, or other voids. In general, the use of aluminum and aluminized... 

Figure 28.2 shows the typical images of three Alclad panels (an aluminum alloy clad with nearly pure aluminum) tested with SO2 salt spray. The panels are (1) chromate conversion coated followed by priming with E-coat (2) chromate conversion coated followed by priming with Deft (chromated spray paint) and (3) plasma coated followed by priming with E-coat. The corroded area and corrosion width are also given in the figure. 

About 75 years ago, the main material for cable sheathing was lead, protected from corrosion by asphalt-impregnated jute coating. Even then corrosion problems prevailed. Later on, extruded or drawn aluminum sheaths were in use, soon to compete with polythene. A large number of failures in the 1960s caused by water in the cable led to the development of sophisticated methods of sheathing involving coated aluminum and clad metals of copper adjacent to a number of steels (45). 

After the application of the aluminum coating to the steel substrate, a heat treatment is often applied. Coatings resulting from vacuum deposition, electroplating, electrophoretic application, cladding, or powder coating techniques are annealed to provide adhesion by diffusion alloying [125],... 

An ideal model system was selected to study the interfacial factors with EIS [19]. The model system was Parylene C-coated Alclad (aluminum-clad aluminum alloy). In this system, the surface state of the top surface (salt solution/coating interface) and the adhesion of the coating (coating/metal interface) were modified to study the influence of these factors on the corrosion protection performance of the system. 

The thermal stability of the stationary phase is also important. Because each stationary phase has a range of thermal stability, it is important to control column temperature within the specified range. For the nonpolar phases, the temperature limit is determined by the stability of the poly-imide coating. The introduction of aluminum clad columns notably broadens the useable temperature range. Oxidation at higher temperatures limits the operating temperature of intermediate to polar phases. 

Electrolytic dissolution in nitric acid has been used at the Savannah River [B22] and Idaho Qiemical Processing plants [AlO, All] to dissolve a wide variety of fuels and cladding materials, including uranium alloys, stainless steel, aluminum, zircaloy, and nichrome. The electrolytic dissolver developed by du Pont [B22], pictured in Fig. 10.4, uses niobium anodes and cathodes, with the former coated with 0.25 mm of platinum to prevent anodic corrosion. Metallic fuel to be dissolved is held in an alundum insulating frame supported by a niobium basket placed between anode and cathode and electrically insulated from them. Fuel surfaces facing the cathode undergo anodic dissolution in a reaction such as... 

LtPSKY, S. R. Duffy, M. L. 1986a. High temperature gas chromatography the development of new aluminum clad flexible fused silica glass capillary columns coated with thermostable nonpolar phases Part 1. Journal of High Resolution Chromatography, 9, 376-382. 

Hundreds of thousands of freight containers have been built worldwide since the early 1960s. They are exposed to many types of climate and are heavily stressed by wear and tear. Freight containers consist of steel or aluminum alloy frames, clad with sidewalls and roofs made of steel, stainless steel, or aluminum alloys. The walls and roofs may be coil-coated. Container frames are usually blasted to grade 2 Vi of the Swedish Standard SIS 055900. 

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