Date: 9 February 2019
Annealed glass suffers from stress corrosion, i.e., the decrease of the tensile strength over time, under load.
The classical theory to account for this phenomenology involves the chemical reaction of water with silica which replaces strong chemical bonds with weaker ones, thus leading to sub-critical growth of the superficial flaws.
In the present work, an innovative polymeric coating produced with the UV-curing technology is developed to protect glass surfaces against stress corrosion.
The new coating is tailored to have a very good adhesion with glass, and an excellent hydrophobic behavior and a very low permeability on the side exposed to the environment. In such a way, it creates a barrier to water and water vapour. The effectiveness of the coating is assessed experimentally on new and naturally aged glass. To this aim, the coating is applied to glass specimens, that are afterwards tested with the coaxial double ring setup.
The results are very encouraging, since an increase of about 75% of the mean tensile strength is obtained compared to uncoated specimens.
Further steps, needed to definitely prove the effectiveness of the coating, consist in assessing the durability of the strengthened glass with respect to mechanical actions and weathering effects.
About the Speaker:
Mauro Corrado is an Assistant Professor of Solid and Structural Mechanics at the Politecnico di Torino, Italy. His research interests include fracture mechanics, computational mechanics, multi-physics and multi-scale analysis, mechanics of materials, structural glass. He is currently leading a project concerning the enhancement of the glass strength by means of functional coatings. He is member of the editorial board of the International Journal of Structural Glass and Advanced Materials Research.