Analysis of Contaminant Films

The cleanliness of components is of great importance in many branches of industry. For e.g. adhesive and joining processes, painting and many other coating processes require clean surfaces in order to obtain perfect results on various substrates such as metals, polymers, glasses or ceramics. Despite state-of-the-art production processes and numerous protective measures to ensure cleanliness, production-related contamination and contamination on surfaces in production often cannot be completely avoided. In the past few years, mainly particulate contaminations from the production processes have been considered. Today, contaminant films have come into focus. Contaminant films arise, for example, from residues of media from production such as oils, greases or cooling lubricants, as well as from the use of other operating aids. Passivation and corrosion protection layers can also be mentioned here as contaminant films. In many cases it is possible to eliminate the problem of contaminant films with simple cleaning steps. However, it can also happen that the cleaning process itself contaminates components and surfaces. Surfactants and additives from the cleaning agents used in the cleaning process can lead to coating and adhesive problems in the next step. Optical inspection and the use of test colors in the laboratories are established methods for controlling cleaning processes. However, if there are persistent particles or if there is evidence of contaminant films, more detailed laboratory analyses are needed to identify possible sources of contamination. In the Tascon laboratory you will find a variety of methods for the analysis of contaminant films. Depending on the exact damage pattern, the use of techniques such as SEM / EDX, FTIR or ToF-SIMS is helpful here. The following example will demonstrate the analysis of a contaminant film.