Internal interlayer delamination

Figure 7-14 Typical forms of delamination (a) vertical splitting, (b) stepped interlayer delamination, (c) circnlar delamination, (d) internal interlayer delamination, and (e) surface blistering.

Internal interlayer delamination is where delamination occurs at the interface between the internal conductor and the ceramic, although the cracks do not reach to the outside of the substrate. The cause of the problem is an area of poor adherence between the green sheet and conductive paste in the laminated body. When there are many layers, or when the conductor on each layer is thick, there is a great difference in the thickness of the parts including the conductor and the parts with ceramic only, so that the laminated body is like a sandwich with a lot of filling (refer to Figure 7-17). Since this delamination occurs in order to release the stress within the laminated body, it takes a similar form to stepped interlayer delamination and circular delamination. 

Figure 7-17 Schema of the mechanism of internal interlayer delamination.

The conditions for dispersing clay nanolayers into both cis-1,4-polyisoprene (IR) and epoxidized natural rubber (ENR) have been reported. The incorporation of the clays into these elastomers was achieved by mixing the components in a standard internal mixer/mixing mill (melt compounding) or by mixing their dispersions produced in toluene or methyl ethyl ketone solvents (solution Intercalation). X-ray diffraction studies indicated the intercalation of IR and ENR into the silicate interlayers, followed by exfoliation (delamination) of the silicate layers. The reinforcing effect strongly depended on the extent of dispersion of the silicate layers. 

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