An example of the use of SEM-EDS to aid in the route cause analysis of a failure in a polymer coating is from a study of defective heat welds on polymer pouches which was resulting in rejection by the customer
Using SEM-EDS analysis, simple comparison of cross-sections of defective welds compared to a control sample of a successful weld shows directly the structure of the material and the defect.
Results clearly show the defective varnish layer causing the heat weld failure. The clear identification of the defect then allows the cause of the failure to be determined.
This process has been recently revolutionised by the advent of AZtecLive, a new breakthrough technology for SEM-EDS allowing real-time imaging of elements in a sample in the SEM. Using AZtecLive, the chemistry of samples can be examined interactively in combination with sample morphology for the first time. For example the defect in the heat welds can now be studied and identified directly without cross-sectioning of the polymer, as shown in this video.