A durable coating to prevent stress corrosion effects on the surface strength of annealed glass

Abstract

The durability of an innovative polymeric coating recently developed by the authors to prevent stress corrosion in annealed glass is herein examined. The coating, having functional graded properties through the thickness, is optimised to provide a very good adhesion with glass and an excellent hydrophobic behavior on the side exposed to the environment, thus creating a good barrier to humidity, which is the triggering agent for stress corrosion. Three scenarios are analysed in terms of ageing: (i) cyclic loading, accomplished by subjecting coated samples to repetitive loading; (ii) natural weathering, performed by exposing coated samples to atmospheric agents; (iii) artificial weathering, carried out by exposing coated specimens to fluorescent UV lamps, heat and water. The durability of the coating is assessed indirectly, on the base of its residual effectiveness in preventing stress corrosion, by comparing the bending strength, obtained with the coaxial double ring test, of aged coated glass specimens with that of un-coated and freshly coated specimens. The obtained results prove that the proposed formulation is almost insensitive to cyclic loading, maintains a very good performance in case of natural weathering, whereas is slightly more sensitive to artificial weathering.

Post-Fracture Stiffness and Residual Capacity Assessment of Film-Retrofitted Monolithic Glass Elements by Frequency Change

“…The residual capacity preservation in case of unfavorable conditions or even accidental actions and events (like impacts [14,15]) is a relevant issue for newly designed glass systems but especially for existing ones, which have been constructed without the technical support of recent design standards and specifications (i.e., [1,2]), and are consequently characterized -in most of cases-by load-bearing and post-fracture criticalities [15]. In case of special performance needs, among others, the use of covering films for glass represents an open research and industrial challenge characterized by the multifunctional potentials, including thermal [16] and corrosion [17] benefits. In terms of structural safety, anti-shatter films can support the post-fracture stage, as they can prevent the spread of critical shards from cracked monolithic glass components (Figure 1 and study by Figuli et al [15]).…”