Problem
Coating delamination: finding the cause
When a coating lifts, blisters or peels, the useful question is where the failure runs and why. It can run along the interface or inside the coating or substrate; the interface may be contaminated; a process or the environment may have changed. Most investigations combine imaging, interface chemistry and, where a number is needed, a mechanical test.
What usually has to be established
- Where the failure runs: along the interface, inside the coating or inside the substrate
- What is on both fracture surfaces, compared with an intact reference
- Whether a change in process, material or storage coincides with the failures
Measurements
Where an investigation often starts.
A typical sequence, not a prescription. The Field Agent adapts it to your sample, what you observed and the decision the result must support.
SEM with EDXStart here
Images both sides of the failure and shows which elements are on each, so you can see where the fracture runs and whether a foreign layer is present.
X-ray photoelectron spectroscopyAlso useful
Can detect thin contamination or oxide layers on an exposed failed interface that conventional SEM-EDX may miss. Vacuum compatibility and any cleaning or sputtering must be agreed.
Cross-section preparationAlso useful
A cross-section through an intact and a failing area shows the layer structure and where cracks start.
Adhesion testingWhen a number is needed
Compares adhesion using an appropriate test: pull-off measures a failure stress, while cross-cut gives a classification. These tests damage the tested area and do not establish the cause on their own.
What to have ready
- Failed samples and intact references from the same batch
- Coating and substrate materials, coating thickness and process history
- When the failure appears: after deposition, curing, thermal cycling, humidity or use
- Whether samples may be cut, coated or sputtered
Potential Dutch, Belgian and German facilities
160 facilities publish at least one of these measurements in Dresden, Berlin, Chemnitz, Enschede, Freiburg, Aachen, Amsterdam, Jena, Karlsruhe, Leipzig, Noordwijk, Stuttgart, Bayreuth, Bielefeld, Brussels, Clausthal-Zellerfeld, Eindhoven, Esslingen am Neckar, Freiberg, Greifswald, Halle (Saale), Hamburg, Hannover, Louvain-la-Neuve, Mainz, Mons, Namur, Rostock, Rudolstadt, Saarbrücken, Schmalkalden, Siegen, Wildau, Aalen, Aschaffenburg, Aschheim, Augsburg, Bad Homburg v. d. Höhe, Bamberg, Biberach, Brandenburg an der Havel, Braunschweig, Breda, Bremen, Bremerhaven, Darmstadt, Deggendorf, Delft, Denkendorf, Diepholz, Duisburg, Erfurt, Erlangen, Frankfurt (Oder), Fürth, Garching, Geesthacht, Gelsenkirchen, Genk, Ghent, Göttingen, Groningen, Gummersbach, Hamm, Hanau, Heilbronn, Ilmenau, Kaiserslautern, Kempten, Kleve, Koblenz, Köln, Krefeld, Lemgo, Liège, Lübeck, Magdeburg, Mannheim, Mittweida, Mülheim an der Ruhr, München, Nürnberg, Oberhausen, Oldenburg, Osnabrück, Paderborn, Petten, Pforzheim, Potsdam, Radeberg, Rüsselsheim am Main, Sankt Augustin, Schwäbisch Gmünd, Seraing, Solingen, Steinfurt, Stralsund, Tübingen, Utrecht, Vianen, Weimar, Weingarten, Weißandt-Gölzau, Wismar, Wolfenbüttel, Würzburg, Zwickau and Zwijnaarde.
Leads are based on published capabilities; current suitability and availability must be confirmed with the laboratory.
Describe your sample and question. The first answer is free and needs no account; laboratory names are shown in a free workspace.