Microstructure coating

Catalyst Developments Requirements and Implemented Techniques for Microstructure Coating... 

CampestiiniP.,TerrynH.,HovestadA. anddeWit J. H. W. (2004), Formation of a cerium-based conversion coating onAA2024 relationship with the microstructure , Coat Teehnol, 176, 365-81. 

The Standard covers bar, plates, sheets, strip, structural shapes rolled stock, pipes, sheets with laminar coating and strip of carbon, alloyed and electrical steels and sets up nondestructive magnetic method of mechanical and service properties and microstructure control. 

Fig. 5. Microstructure of a cemented carbide alloy, 86%WC—8%(Ti,Ta,Nb)C—6%Co, with a cobalt-enriched periphery and a TiC—TiCN—TiN coating.

The specimen in Fig. 17.15 is part of a cast iron pump impeller. The spongelike surface contours are apparent, as is the black coating that covers surfaces exposed to the cooling water. Microstructural examinations revealed preferential deterioration of the iron matrix surrounding the graphite flakes. 

Slides Microstructures of oxide layers and oxide-resistant coatings on metals and alloys selective attack of eutectic alloys [5]. 

As with chemical etches, developing optimum conversion coatings requires assessment of the microstructure of the steel. Correlations have been found between the microstructure of the substrate material and the nature of the phosphate films formed. Aloru et al. demonstrated that the type of phosphate crystal formed varies with the orientation of the underlying steel crystal lattice [154]. Fig. 32 illustrates the different phosphate crystal morphologies that formed on two heat-treated surfaces. The fine flake structure formed on the tempered martensite surface promotes adhesion more effectively than the knobby protrusions formed on the cold-rolled steel. 

Tinplate and Solder. Metallurgical studies were performed to determine the effect of irradiation at low temperature on the corrosion resistance of tinplate and on the mechanical properties and microstructure of tinplate and side-seam solder of the tinplate container. The area of major interest was the effect of low-temperature irradiation on the possible conversion of the tin from the beta form to the alpha form. In the case of pure tin, the transition occurs at 18 °C. It was feared that low-temperature irradiation would create dislocations in the crystal lattice of tin and enhance the conversion of tin from the silvery form to a powdery form rendering the tin coating ineffective in protecting the base steel. Tin used for industrial consumption contains trace amounts of soluble impurities of lead and antimony to retard this conversion for several years. 

The metallurgical experiments showed that the beta-alpha transition of the tin coating did not occur at irradiation doses of 3-5 Mrad and 6-7.5 Mrad at 5, —30, and —90°C and that the tensile properties, impact ductility, peel strength of soldered lap joints, and microstructure of commercial tinplate and solder were not affected by the irradiation conditions that are used in the sterilization of meat products. 

Dimigen, H. and Klages, C. R, Microstructure and Wear Behavior of Metal-containing Diamond-like Coatings, Surf. Coat. Technol, Vol. A9,1991,pp. 543-547. 

As a result, scale layer was always formed on the smooth surface of reactor wall as well as irregular. Microstructure was blanketed as soon as the surface was coated with a Ti02 scale film. It could be deduced that once scales were formed, the effect of surface geometrical shape would be more important than its microstructure. 

On the other hand, Xiao et al. [215] reported that smooth, dense, and erystalline PbTe films with nearly stoichiometric composition could be obtained by an optimized electrodeposition process from highly acidic (pH 0) tellurite solutions of uncomplexed Pb(II), on Au-coated silicon wafers. The results from electroanalyti-cal studies on Te, Pb, and PbTe deposition with a Pt rde at various temperatures and solution compositions supported the induced co-deposition scheme. The microstructure and preferred orientation of PbTe films was found to change significantly with the deposition potential and electrolyte concentration. At -0.12 V vs. Ag/AgCl(sat. KCl), the film was granular and oriented preferentially in the [100] direction. At potentials more negative than -0.15 V, the film was dendritic and oriented preferentially in the [211] direction (Pig. 3.13). 

Eichtner, M., Benzinger, W., Hass-Santo, K., Wunsch, R., Schubert, K., Functional coatings for microstructure reactors and heat exchangers, in Ehrfeld, W. (Ed.), Microreaction Technology 3rd International Conference on Microreaction Technology, Proc. of IMRET 3,... 

A Pt/AljOj coated microstructured reactor/heat exchanger for the controlled H2/02-reaction in the explosion regime, in Ehreeld, W., Rinaed, I. H., Wegeng,... 

Haas-Santo, K., Eichtner, M., Schubert, K., Preparation of microstructure compatible porous supports by sol-gel synthesis for catalyst coatings, Appl. Catal. A 220 (2001) 79-92. 

A Pt catalyst was applied by dry and wet techniques. By means of sputtering using a mask process protecting parts of the microstructure, the micro channel bottom was coated selectively. In addition, an y-alumina layer was applied by the sol-gel technique. Initially, the whole micro structure was covered by such a layer. Then, photoresist was applied and patterned so that only the channel part remained covered. After removal of the exposed photoresist and unprotected y-alumina, only the channel bottom was coated with y-alumina. 

Activity of the same catalyst coating on different microstructured materials... 

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