Strength Improvement of Glass Substrates by Using Surface Nanostructures

Abstract

Defects and heterogeneities degrade the strength of glass with different surface and subsurface properties. This study uses surface nanostructures to improve the bending strength of glass and investigates the effect of defects on three glass types. Borosilicate and aluminosilicate glasses with a higher defect density than fused silica exhibited 118 and 48 % improvement, respectively, in bending strength after surface nanostructure fabrication. Fused silica, exhibited limited strength improvement. Therefore, a 4-μm-deep square notch was fabricated to study the effect of a dominant defect in low defect density glass. The reduced bending strength of fused silica caused by artificial defect increased 65 % in the presence of 2-μm-deep nanostructures, and the fused silica regained its original strength when the nanostructures were 4 μm deep. In fragmentation tests, the fused silica specimen broke into two major portions because of the creation of artificial defects. The number of fragments increased when nanostructures were fabricated on the fused silica surface. Bending strength improvement and fragmentation test confirm the usability of this method for glasses with low defect densities when a dominant defect is present on the surface. Our findings indicate that nanostructure-based strengthening is suitable for all types of glasses irrespective of defect density, and the observed Weibull modulus enhancement confirms the reliability of this method.

Successive Surface Reactions on Hydrophilic Silica for Modified Magnetic Nanoparticle Attachment Probed by Sum-Frequency Generation Spectroscopy

“…Surface modification of silica-based substrates allows the alteration of the physicochemical properties that are most needed in several applications, especially in optoelectronics. − Reacting trialkoxy- or trichlorosilane with specific terminal groups with hydroxylated silica surfaces is one of the most common and convenient ways to tailor surface properties. , Specifically, the radical-based thiol–ene reaction, a member of the click reaction class, is attractive among other commonly used reactions. The reaction can take place under mild conditions even in the presence of oxygen, , can be run neat or in solvents, provides high yields, does not require catalysts, and can use a number of commercial precursors to provide various terminal groups as needed. ,, Successive surface thiol–ene reactions involve the step-by-step functionalization of the hydroxylated substrate.…”