Multilayer techniques

Multilayer coatings or hlms have been proven to be successful in various applications, especially for wear protection. In multilayer systems, the intrinsic stress can be effectively reduced by designing interface number and composite materials in terms of the application and process technique. Therefore, the multilayer technique by which a specihe functional composite is able to approach received more attention for many years [17,18]. Here we introduce the results on microscale friction and scratch of DLC/DLC and Fe-N/TiN multilayers. 

Elbert DL, Herbert CB, Hubbell JA (1999) Thin polymer layers formed by polyelectrolyte multilayer techniques on biological surfaces. Langmuir 15 5355-5362... 

The choice of materials for metallic systems is still expanding and at present various examples of combinations with different atomic radii are being prepared. Here multilayered techniques also show possibilities for new material syntheses. In contrast to materials prepared by chemical procedures, supedattices are made far from equilibrium. The various possibilities for layering the artificial supedattice materials are given in Figure 16c—f. Most of the stacked layers (c, d, f) have more or less sharply defined boundaries and some have a noncrystalline structure in the individual layers (c) or one of the layers is noncrystalline (d). In such situations the structural information is not transmitted between adjacent layers and therefore, stricdy speaking, no supedattice is formed. In the case of an unsharp boundary (e), compositionally modulated alloy-layered structures have been made. The amplitude of composition modulation in the center of a layer can be in the range of 0 to 100%. Supedattices can also be formed with sharp boundaries (<5% of the thinnest layer) between the two components. 

E282 Ratge, D., Kohse, K.P., Knoll, E. and Wisser, H. (1986). Evaluation of the multilayer technique using thin-film elements for analysis of electrolytes, substrates and enzymes. Poster presented at Gemeinsame Jahrestagung der Deutschen, Schweizerischen, Osterreichischen und Franzosischen Gesellschaft fiir Klinische Chemie, Basel, 22-25 October. 

The technique of interspersing a layer with thin layers that eliminate pinhole formation can be applied to other systems as well. The method is, for example, successful in ST0/PrBa2Cu30y multilayers [14.70]. A layer-by-layer growth mode favors high quality multilayers with large critical thicknesses. The multilayer technique also opens possibilities to continuously vary the physical properties of the intermediate layers by combining two materials with different behaviors. 

The thermo-mechanics may be an issue in the case of a fine positioning application over a large range of temperature the PZT in the multilayer technique display various coefficient of thermal expansion, CTE (as a function of some construction details). Standard amplified piezo actuators displays fairly large CTE due to some thermal mismatch between the piezo component and the shell material. There are some possibilities to cancel this CTE in the application ... 

Mincsovics et al. (67) found that OPLC was suitable for the development of several chromatoplates simultaneously if the plates were specially prepared. With this multilayer technique, a large... 

The focus in the thin film research impact area is to develop a fundamental understanding of how morphology can be controlled in (1) organic thin film composites prepared by Langmuir Blodgett (LB) monolayer and multilayer techniques and (2) the molecular design of membrane systems using ionomers and selected supported liquids. Controlled structures of this nature will find immediate apphcation in several aspects of smart materials development, particularly in microsensors. 

Figure 5.9 Comparison of catalytic activity by multilayer technique to experimental data.

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