This non-destructive test enable to observe the structure of a material, without having to take a sample of it. This test allows to reveal phenomena of damage or microstructural aging or to understand the nature of phenomena of fatigue, corrosion, etc.
After having performed an adequte preparation of the surfaces and executed a metallographic attack, the replica is taken using a cellulose acetate film. Then, the film is fixed on a glass slide and observed under an optical and/or electron microscope.
The investigation can have several purposes: acceptance of materials; assessment of microstructural damage following overheating, fires; assessment of aging phenomena during operation and residual life estimates.