Metallic interlayer

X-ray diffraction patterns yield typical 1.2—1.4 nm basal spacings for smectite partially hydrated in an ordinary laboratory atmosphere. Solvating smectite in ethylene glycol expands the spacing to 1.7 nm, and beating to 550°C collapses it to 1.0 nm. Certain micaceous clay minerals from which part of the metallic interlayer cations of the smectites has been stripped or degraded, and replaced by expand similarly. Treatment with strong solutions of... 

Metallic interlayer (MIL) influences the chemical processes of FR. The role of metal ions in the degradation process has been summarized by Lewin and Endo [30], The advantageous effect of a MIL around metal hydroxide flame retardants was utilized at first by Hornsby et al. [31]. They proposed a zinc-hydroxy-stannate (ZnHSt) layer, the detailed chemical-physical structure and 4.7 nm thickness... 

It has been shown that electroactive polymer films on electrodes can mediate electron transfer for metal deposition (9-11). Haushalter and Krause (5) have described the treatment of PMDA-ODA films with highly reactive Zintl complexes (e.g., Sn9 4, SnTe4 4) to yield an intercalated material able to reduce ions of platinum, palladium and silver at the film surface. Mazur et al., (12) reported the deposition of conductive Ag, Cu, and Au metal interlayers within a PMDA-ODA film by electrochemical reduction. 

Recently, the introduction of a metallic interlayer between a coating deposit and its substrate and its effects on mechanical properties were studied. The authors experimented with a multilayer approach a metallic layer sandwiched between two highly reactive layers. For the SiC system, no previous reference on the interposition of a ductile layer between the deposit and the substrate was found, and that motivate the study reports here. 

The initial approach in this study was to demonstrate the use of metallic interlayers and/or coatings in the bonding procedure. For the first layer (intended for the metallurgical bonding of the ceramic), Ti and Cr were found to be the most promising metals. Here both coatings (by PVD, 1-10 0.m thick) and layers of foils (25 im thick) were used. The function of the second Ta layer of 25 im thickness was to suspend the diffusion of Ti between the foils. In all of the experiments the third layer of niobium of 2 mm thickness was applied for thermal residual stress relief. The multilayered joint microstructure is shown in Fig. lb [7]. 

Jadoon, A.K., Ralph, B., and Hornsby, P.R., Metal to ceramic joining via a metallic interlayer bonding technique, J. Mater. Proc. Techn. 152 (2004) 257-265. 

Y.S. Chou, J.W. Stevenson, and L.A. Chick, Novel compressive mica seals with metallic interlayers for solid oxide fuel cell applications. Journal of the American Ceramic Society, 86(6) (2003) 1003-1007. 

The nitride of one of the metals has a low Gibbs energy. A system of nitride grains surrounded by the crystalline metal interlayer is formed, for example, nc-CrN/Cu, nc-CrN/... 

A representative TBC system for a gas turbine engine comprises four layers (a) a metallic substrate, that is, the turbine blade itself, (b) a metallic interlayer or bondcoat, (c) a thermally grown oxide (TGO), and (d) a ceramic outerlayer or topcoat. A schematic of the turbine blade along with a scanning electron micrograph of the cross-section of a layered TBC coating is shown in Figure 1.7. 

Cobalt doping greatly reduces nonstoichiometry of LiNA and makes its structure stable so that the properties of the Co-doped materials are improved. Since cobalt (0.053 nm) has a smaller ion radius than nickel (0.056 nm), the a parameter relative to the metal-metal interlayer distance in the MOg layer and the c parameter, which is three times the interlayer distance, decrease slowly with an increase in the doping amount of cobalt, and the ratio of c/a indicating its structure anisotropy increases. The changes in these parameters indicate that the 2-D layered characteristics in this material are... 

Adsorption does not cause reconstruction on bcc(llO), cf. Table 7. (There have been reports of a possible H-induced lateral shift of the top metal layer but later studies could not confirm these results.) Adatoms appear to favor the "center" site (which is the continuation site of the bcc lattice), even though it is only two-fold coordinated. Adjacent to this site is a three-fold coordinated hollow site which is preferred by hydrogen, while in one structure, Mo(110)+(2x2)-S, the adatom appears to settle midway between those two sites. The adsorbate does not seem to induce a systematic expansion of the outermost metal-metal interlayer spacing on bcc(llO) this is somewhat surprising in view of the results on other surfaces, but perhaps the statistics in this small group of results are not sufficient to reach a firm conclusion. 

Ru(0001)h- (2xl)-H LEED no no 1.8 2.8 0.9 2.8 complex 0 1.32 0.2 1.34 0.2 0 92H2 adsorption roughly on threefold fee sites buckling and pairing reconstruction of the first metal layer slight expansion of the first metal interlayer spacing... 

Ru(0001)h-(V3xV3) R30°-2H20 1 H20athigh top site LEED no no 4.2 0.9 0 0.5 0.9 -2.8 0.9 0 0 0 0 0 0 2.23 0.02 0 94H1 intact molecular adsorption in two different top sites (bilayer) on unreconstmeted relaxed substrate significant buckling in top metal layer contraction of first two metal interlayer spacings... 

Singh, M., Martinez Fernandez, J., Asthana, R., Rico, J. R. (2012). Interfacial characterization of silicon nitride/silicon nitride joints brazed using Cu-base active metal interlayers. Ceramics International, 38, 2793-2802. doi 10.1016/j. ceramint.2011.11.050. 

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