Aluminum coatings, applications

The waterborne basecoat consists of a urethane or an acrylic dispersion with passivated aluminum for metallic glamour. The aluminum must be passivated to prevent reaction with water and the evolution of hydrogen gas. Passivating agents can include polymers, hexavalent chromium (now mandated for removal), or phosphate esters. The basecoat is pre-baked (with infrared or thermal ovens) to release the majority of the water prior to clear-coat application. 

The final type of storage is the optical drive. Optical drives work by using a laser rather than magnetism to change the characteristics of the storage medium (typically an aluminum-coated plastic disk). Optical drives look similar to and are used for the same applications as Zip drives (e.g. archival storage and large file transport). However, optical drives can store more information and have slower access times than Zip drives. 

The spatial light modulator used in our system is a modified DMA chip by Texas Instruments (DMD 0.7 XGA 12° DDR). The array consists of 1024 x 768 aluminum coated individual micromirrors of 14p,m x 14p,m each, capable of 12° tilt relative to the diagonal. Mirrors are individually addressable through a driver circuit available from the manufacturer. For IR applications, the original glass window needs to be replaced with an IR-transparent window. We have developed the technology to mount coated ZnSe windows on Texas Instraments DMA chips and preserve long lifetime of the chip. 

Heimann, R.B., Kleiman, J.I., Litovsky, E., Marx, S., Ng, R., Petrov, S., Shagalov, M., Sodhi, R.N.S., and Tang, A. (2014) High-pressure cold gas dynamic (CGD)-sprayed alumina-reinforced aluminum coatings for potential application as space construction material. Surf. Coat. Technol., 252, 113-119. 

Conventional SB systems, with unlimited solvent use, are estimated to have accounted for 31% of the dollar volume of IF shipments in 1982 they are expected to decrease to 12% in 1987 as the full effects of environmental regulations are established. Conforming SB systems, that is, those conforming to the revised California Rule 66, CARB (California Air Resources Board) codes, and the evolving EPA regulations, will decrease at a lower rate, from 34% in 1982 to 22% in 1987. These include the use of certain chlorinated solvents (e.g., 1,1,1-trichloroethane and methylene chloride) that have been exempted by several regulatory authorities. However, problems with reaction with coating application equipment components made of aluminum may impede their full utilization. 

In metallurgical practice, sodium uses include preparation of powdered metals removal of antimony, tin, and sulfur from lead modification of the structure of silicon—aluminum alloys application of diffusion alloy coatings to substrate metals (162,163) cleaning and desulfurizing alloy steels via NaH (164) nodularization of graphite in cast iron deoxidation of molten metals heat treatment and the coating of steel using aluminum or zinc. 

A nonwoven mat of smooth flexible aluminum coated oriented glass fibers, Metafil, has been developed by Tracor Aerospace and BGF Industries, USA, for electrically or thermally conductive applications, such as parabolic dish antennae. It is compatible with most resin systems and processing is said to be similar to uncoated glass mat, but cost is lower than other conductive materials. 

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],... 

The applications of aluminum-coated steels are dictated by the nature of their coatings aluminum coatings for corrosion resistance and iron-aluminum coatiugs (i.e., diffusion coatings) for oxidation resistance. 

Even if oxide films are completely removed by the above processes, they will spontaneously redevelop at a rate dependent on temperature and humidity. For example, after a few days in humid air, pure aluminum forms thin but dense natural oxide layers 2-10 nm thick, generally considered to consist of amorphous AI2O3. One such air-grown film had a resistance of 35 kXl cm, suggesting that the film structure contained defects or micropores [201]. Thus, it maybe important to control or at least specify the environment to which the metal substrate is subjected, if there is a significant time interval between surface preparation and coating application. 

Phenolics that are not heat-reactive may be incorporated into both air-dried and baked oleoresinous coatings. Applications vary widely and include clear and pigmented exterior varnishes, aluminum-maintenance paints, zinc-rich primers, can coatings, insulation varnishes, and concrete paints. As modifiers in a great variety of applications, they enhance the performance of oleoresinous and alkyd coatings. 

TVnother continuously coated steel sheet product. Type 1 aluminum-coated, is made by hot dipping in a molten bath of aluminum containing 5-11 % silicon [79]. Typ>e 1 coatings are thinner, typically 10-20 pm, and are more foimable than T5rpe 2 coatings. This product is widely used in high-temperature applications (up to 675°C), particularly for automobile tailpipes and mufflers. 

Galfan finds application in a mild urban-industrial atmosphere and in a marine atmosphere. This latter application is particularly important because the corrosion rate slows after about 4 years, whereas conventional galvanized steel should show rust in 5 years. This slower rate of corrosion is evidence that the zinc-5% aluminum coatings provide full cathodic protection to cut edges over a longer period of time. 

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