In most float glass productions, quality control systems will remove glass inclusions with sizes above 500µm, since smaller inclusions are usually not visible to the human eye. Yet, they can still become relevant in glass construction, one example being nickel sulphide which can cause spontaneous fracture of safety glass. This research presents statistical data on the prevalence of inclusions in the size range from 50 µm to 500 µm, obtained from thorough scans of commercial glass. Also, many of the found inclusions are investigated by ultra-high-resolution microscopy down to the physical limit of visual inspection. Images taken under different lighting conditions and with different types of microscope cameras help in the identification and differentiation of inclusion types. Photoelastic stress measurements and laser interferometry also show stress and deformation inside the glass around inclusions. Due to the risks emerging from this inclusion type, a special focus of the presented work is on the identification of nickel sulphide and its precursors.
Appearance, properties and prevalence of small glass inclusions
Company: Technische Universität Darmstadt, Darmstadt, Germany
About the speaker:
Timon Peters studied both civil engineering and architecture at Technische Universität Darmstadt in Germany. After short work as a structural engineer in glass engineering, he joined the Institute of Structural Mechanics and Design at Technische Universität Darmstadt in 2017 where he focuses his research on nickel sulphide inclusions in safety glass and on applications of thin glass in architecture.