Failure modes, adhesion definition

The first three chapters discuss definitions, adhesion theories, surface characterization and analysis, surface energy measurement methods, adhesion mechanism, failure modes, and surface treatment of materials. 

The often used FPL etdi of an aluminum-lithium alloy bonded with polysulfone leads to interfacial (at the metal oxide/polymer interface) failure (38) which is a surprisingly uncommon type of failure. The results leading to this assignment are shown as XPS C Is and O Is narrow scan spectra in Figure 15. This definitive assignment of failure mode is based on the fact that one failure surfece has an oi gen photopeak similar to the pretreated adherend before bonding and the other failure surfece has an 0 gen photopeak similar to the adhesive. 

Whatever the definition might be, for space applications, the loads taken into account for the design are those calculated, increased by the margin factor for the considered application, and the cohesive failure mode (in the adhesive or in the adherends) will be the mode expected. 

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