The SFA technique allows to measure simultaneously and independently the absolute surface separation, D, between the alumina surfaces and the refractive index of the medium, BADGE/JeffAmine mixture, B/JA. These two parameters (D and B/JA), when properly interpreted, are sufficient to monitor the grade to which the alumina-BADGE/JeffAmine interface changes during cure in different environmental conditions. Interface changes can be asperity formation (roughness), wetting or de-wetting (increase or decrease of the alumina-BADGE/JeffAmine contact area, respectively), condensation of vapors at the three-phase alumina- BADGE/JeffAmine/air contact line, 10 diffusion, or crosslinking of the epoxy matrix. All of the aforementioned changes dictate the effectiveness of the metal oxide-epoxy bond, that is, the alumina-BADGE/JeffAmine bond. The FECO sequence of BADGE/JeffAmine cured at 0 %RH is shown in Figure . Schematics show one possible FECO interpretation. Initially, at tcure = 0 hrs, a BADGE/JeffAmine droplet of 375 µm in diameter bridged surfaces at a separation of 8 µm. During the first hrs of cure (up to tcure = 22 hrs), the surface separation decreased to 25%, a point at which fibrillation FECO signatures appeared. The additional FECO discontinuities, Figure , can show this fibrillation (and possible loss of adhesion area). It is important to note that their presence could be initiated several hours before being detected with FECO (FECO is collected from a cross-sectional area of 450 µm and 10-20 µm in width, typically located around the center of the PCA). It is possible to incorporate lateral scanning capabilities to monitor the detection of any changes across the entire area of interest, as tested and described in S2. Monitoring large areas with FECO. In summary, we show the feasibility of tracking phenomena at the interface in situ and in ipsa hora.