Oil&Gas, Aeronautical, Industrial 

The formation of a crack leave its mark, even "acoustically". 

Based on this consideration, materials and coatings can be studied using instruments that measure the Acoustic Emission (AE). 

A typic application concerns the coatings. Some coatings give the steel excellent properties of  wear, high temperature or corrosion resistance… 

Designers of different sectors widely exploit these features with the aim of protecting the structural properties of the base metal. 

Obviously, the integrity of the cladding grants the useful life of the structural material. 

But what happens to the coating when the material faces a deformation? To what degree can the base material be strained without damaging the cladding ? 

The answers to this queries would be particularly useful for the design, but they are not always available. 

The combination of a TENSILE test + the determination of the ACOUSTIC EMISSION (AE) gives a wider view. We use AE piezoelectric sensors with a frequency range of 100 to 450 kHz and service temperatures between -50°C and 100°C. 

Performing this kind of combined test we record loads and deflections which cause the first cracking and a sibsequent flow of cracks; 

we bring visible what would not be detectable  from the Stress VS Strain curve. 

So we define the critical strain beyond which a specific coating loses its integrity and exposes the base material to a possible attack. 

The mechanical resistance curve, enriched by the acoustic emission, gives the designers precious information.