Glass Corrosion Research Articles

XPS analysis of damp heat aged and fractured polymer/glass laminates

Essential for the durability of photovoltaic (PV) modules is the polymeric encapsulant. In addition to the well-established ethylene vinyl acetate copolymers (EVA), polyolefin elastomers (POE) are gaining market relevance. The main objective of this paper was to elucidate the ageing and degradation mechanisms of PV relevant glass laminates based on UV-transparent EVA and POE encapsulants by X-ray photoelectron spectroscopy (XPS).Special focus was given to the polymer/glass interfaces. Therefore, glass laminates were damp heat aged and debonded by monotonic compressive shear testing. Subsequently, the polymer side of the fractured surfaces was characterized by XPS and Fourier-transform infrared spectroscopy (FTIR). The polar EVA encapsulant revealed more pronounced deterioration than the less polar POE material.Significant differences were already discernible after 1kh of damp heat exposure. The diffusion of Na ions from the glass substrate into the polymer matrix and the formation of Na salts at the interface were ascertained for EVA and to a less extent also for POE. While EVA laminates failed primarily close to the interface, but still within the EVA material, glass residues were detected on the fractured POE surfaces indicating interface-near glass corrosion and a fracture path propagating back and forth within POE and glass.

Characterization of the Alkali and Hydrolysis Resistance of Polymer-Impregnated, Alkali-Resistant Glass Filaments.

The aim of this series of tests was to characterize the alkali and water resistance of alkali-resistant (durability) glass filaments, which were optimized with two non-vulcanized formulations based on co-polymerizing styrene-butadiene rubbers (CemFil-SBR1 and CemFil-SBR2). Furthermore, it was assessed which of the two polymer-impregnated multifilament yarns is the better alternative for use in cementitious binders. For this purpose, the impregnated multifilament yarns were chemically conditioned for up to twelve months at temperatures of 23 and 50 °C in 2.5 percent sodium hydroxide solution and 2.5 percent potassium hydroxide solution as well as in 3 percent salt and distilled water. The samples were then subjected to material science tests. The liquid absorption capacities and the changes in the mass of the composite materials were determined at different times during conditioning. The load-bearing capacity of the samples was also tested using uniaxial fiber strand tensile tests. The durability of the polymer-impregnated multifilament yarns was described in detail in conjunction with scanning electron microscopy images and nominal cross-section determinations. The test liquids caused a reduction in strength during the storage period, which was accelerated by increased temperatures. The reduction in strength is mainly due to glass corrosion of the filaments. Glass corrosion is delayed due to the good impregnation quality, which fundamentally improves the durability of the yarns. The results of the durability tests show that the polymer-impregnated multifilament yarns CemFil-SBR2 are probably more suitable for use in cementitious binders, as they have better alkali and hydrolysis resistance.

Exploring the corrosion mechanism of oxide glasses using advanced solid-state nuclear magnetic resonance spectroscopy

Despite over 70 years of study, the mechanism of glass corrosion, particularly the formation of the amorphous alteration layer known as the gel layer, remains a subject of controversy. A critical debate revolves around the origin of the abrupt change in chemical concentration near the interface between the gel layer and the glass phase. The prevailing concept attributes this shift to the dissolution of glass compositions, followed by their precipitation onto the glass surface, ultimately forming the gel layer. In this study, we utilized state-of-the-art solid-state nuclear magnetic resonance (SSNMR) techniques to track the atomic-scale network evolution of phosphate glass and borosilicate glass during corrosion. The SSNMR results demonstrate that water partially disrupts the glass network at the surface but hardly disrupts the glass network of the hydrated glass phase. This distinct interaction leads to different structures at the surface compared to the hydrated glass phase. A significant exchange of alkali metal ions in the glass occurs with H species (H+ or H3O+) in the surrounding water. Our findings demonstrate that the ion-selective diffusion, combined with the structural difference between the gel layer and hydrated glass phase, rather than the dissolution-reprecipitation of glass compositions, is responsible for the formation of a gel layer on the glass surface and the abrupt change in chemical concentration near the interface between the gel layer and the hydrated glass phase. These new findings provide valuable and novel insights into the corrosion mechanism of oxide glasses.

Enhanced photoluminescence properties and stability of CsPbBr3 quantum dots borosilicate glasses modified by ZnO

Halide perovskite quantum dots (QDs) glass has attracted much attention in the field of optoelectronics, but its photoluminescence (PL) properties and water stability still need further improvement. In this work, the melt-quenching method is used to successfully precipitate CsPbBr3 QDs in borosilicate glass. By increasing the concentration of ZnO, the photoluminescence quantum yield (PLQY) of CsPbBr3 QDs glass is enhanced up to 30 times from 1.91 % to 65.87 %. The results demonstrate that the introduction of ZnO loosens the glass network structure, which contributes to the QDs to precipitate. In addition, it can be found that the PL intensity maintains 91.68 % of the initial PL intensity after 30 days of immersion, which is attributed to ZnO delays the corrosion of borosilicate glass by water. The effect of ZnO-modified borosilicate glass structure on PL and stability provides a certain reference value for further research on QDs glass, and the good PLQY and water stability make ZnO-modified CsPbBr3 QDs glass a potential material in the field of WLEDs.

UAV imagery-based railroad station building inspection using hybrid learning architecture

The apparent defects of railroad station building such as the broken glass, missing screw, and rust corrosion need to be inspected regularly and timely to ensure the safety of passenger. Unmanned aerial vehicle (UAV) imagery-based inspections have the potential to revolutionize current manual visual inspections by providing a better overhead view and mitigating safety concerns. This paper proposes a hybrid learning architecture called YOLOS (you only look once station scene) to simultaneously detect and segment station building surface defects of UAV images. First, a novel squeeze-and-excitation (SE) attention block is integrated into the detection branch to adaptively learn the weights of the feature channels, thereby promoting the network to pay attention to the critical deep features of the objects. And then, a new semantic segmentation branch parallel to the detection branch is designed and assembled in YOLOS for pixel-level defect recognition. Finally, extensive experiments on railroad station dataset established with drone imagery prove the effectiveness and robustness of the SE-based network on station surface defect detection. This method can quickly convert UAV imagery into useful information with a high detection rate.

Influence of glass-phase structure on the degradation of rare-earth (Y2O3, La2O3)-doped CaO–Al2O3–SiO2–B2O3 glass-ceramics in citric acid solution

Liquid-phase sintering anorthite (LSA) glass-ceramics with degradation in citric-acid solution have been prepared from CaO–Al2O3–SiO2–B2O3 low-melting compositions. By means of the chemical corrosion of the glass phases, LSA glass-ceramics are effectively degraded in the citric acid solution. Then, the influence of B2O3 and rare-earth (RE) on the structures of glass phases, the degradation of LSA glass-ceramics in the citric-acid solutions, and the dielectric properties are investigated systematically. The results suggest that when the B2O3 molar ratio in the composition CaO–Al2O3–SiO2–B2O3 is 0.5, doping LSA glass-ceramics with RE can reduce the quantity of bridging oxygen and [BO4] units in the glass phase, as well as the degree of network connection of [AlO4] units in the glass network. Conversely, when the B2O3 molar ratio is decreased down to 0.3, doping RE into LSA glass-ceramics increases the quantity of bridging oxygen and [BO4] units for glass phase. This improvement in chemical stability effectively impedes the degradation of LSA glass-ceramics in citric-acid solutions. Concurrently, the degradation mechanism of LSA glass-ceramics in citric acid solution is analyzed and explained in terms of classical glass corrosion theory, while the microstructural characteristics of LSA glass-ceramics are utilized to investigate their dielectric properties. It indicates that the dielectric loss and dielectric constant of LSA glass-ceramics are significantly lowered as a result of the existence of the glass phase. Especially when the B2O3 molar ratio in the composition CaO–Al2O3–SiO2–B2O3 is 0.3, and the La2O3 doping percentage into LSA glass-ceramics is 0.5 wt%, the LSA glass-ceramics exhibit the lowest dielectric loss value of 3.13 × 10−3 and εr = 4.17. Developing the LSA glass-ceramic with degradation in organic acids can provide a new idea for the recycling and disposal of e-waste.

Synergy between Ca2+ and high ionic field‐strength cations during the corrosion of alkali aluminoborosilicate glasses in hyper‐alkaline media

AbstractOne major factor impeding the design of nuclear waste glasses with enhanced waste loadings is our insufficient understanding of their composition–structure–durability relationships, specifically in the environments the waste form is expected to encounter in a geological repository. In particular, the high field‐strength cations (HFSCs) are an integral component of most waste streams. However, their impact on the long‐term performance of the glassy waste form remains mostly undeciphered. In this context, the present study aims to understand the impact of some HFSCs (i.e., Nb5+, Zr4+, Ti4+, and La3+) on the dissolution behavior of alkali/alkaline‐earth aluminoborosilicate‐based model nuclear waste glasses in hyper‐alkaline media. At pH = 13, the studied glasses dissolve through the dissolution–reprecipitation mechanism, with Ca precipitation being the most vital step to passivation. In Ca‐free glasses, although the HFSCs slow down the forward rate, they do not seem to impact the residual rate behavior of glasses. The presence of Ca2+, however, initiates the rapid precipitation of network polymerizing HFSCs (i.e., Nb5+, Zr4+, and Ti4+) into a Ca2+/HFSCs‐based passivating layer, thus suggesting a synergy between Ca2+ and HFSCs that contributes to the enhanced long‐term durability of the glasses. Such synergy is not strongly evident for La3+, but instead, a potential La/Si affinity is observed upon the formation of the alteration layer.

Formation and evolution of secondary phases and surface altered layers during borosilicate glass corrosion in pore water

The emergent secondary phases and surface altered layer (SAL) during the aqueous corrosion of borosilicate glass have a great impact on its chemical durability. However, the formation and evolution of these structures are still unclear. Here, by studying the borosilicate glass altered at 90 °C in pore water, the water in pore space between glass powders, the formation of secondary phases could follow two ways: 1. the consumption of aqueous ions forms analcime, zeolite, calcium silicate and barite at the surface of glass; 2. the reorganization of silica aggregates leads to smectite within the SAL. Small-angle X-ray scattering and cross-sectional scanning electron microscopy results show that the release of soluble elements and the formation of smectite within the SAL significantly increase the porosity of SAL. Furthermore, the layer containing smectite reorganizes inwardly and the crystallinity of smectite is gradually increased over time. The observations of transmission electron microscopy reveal that the dissolution of glass potentially goes through an interface-coupled dissolution-reprecipitation process.

Application of hyperspectral imaging for characterization of VOC-induced historical glass corrosion

Hyperspectral imaging (HSI) provides high-resolution recording of the spectral information at every spatial point (pixel) of an object throughout a contiguous range of wavelengths. This paper reports an attempt at exploring the application of HSI in transmittance mode for the identification and quantification of corrosion in transparent historical glass, which is difficult to identify by visual inspection. This was done using model glass samples mimicking historical composition and subjected to artificial ageing in the presence of volatile organic compounds. Hyperspectral images of unaged and aged glass samples were recorded with two cameras covering visible and near infrared (VNIR, 400–1000 nm) and short-wave infrared range (SWIR, 1000–2500 nm) using a custom-made HSI set-up in transmission mode. The HSI data were further processed to classify and visualize corrosion in different ageing environments and ageing periods. The results show that HSI can be employed as a valuable tool to assess glass corrosion at early stages, especially by analysing the SWIR spectral region—which shows the water absorption by the glass matrix due to corrosion.

Formation Mechanism of Crystalline Phase during Corrosion of Aluminum Phosphate Glasses

Formation Mechanism of Crystalline Phase during Corrosion of Aluminum Phosphate Glasses

Application of the immobilized low-activity waste glass corrosion model to the static dissolution of 24 statistically-designed alkali-borosilicate waste glasses

Glass corrosion models that capture the complex mechanisms of the glass-water reaction enable the prediction of nuclear waste glass durability in disposal scenarios. Parameterization of such models is challenging because of the need to capture changes in corrosion behavior with time, reaction conditions, and glass composition. Here, we describe and employ the ILAW (immobilized low-activity waste) glass corrosion model (IGCM) in geochemical simulations of static dissolution tests, at two temperatures (40 °C and 90 °C), for a matrix of 24 enhanced low-activity waste (eLAW) glasses statistically designed to cover a processable composition space defined by 8 major glass components (Al2O3, B2O3, CaO, Na2O, SiO2, SnO2, ZrO2, and Others as defined in the text). The IGCM includes a first-order chemical affinity term and an ion-exchange term that represents the net exchange of Na+ ions in the pristine glass with protons in aqueous solution. Constant, time-dependent, and time- and pH-dependent functional forms of the ion-exchange term are evaluated to reproduce the change in corrosion behavior with time in saturated, static dissolution tests. The agreement with measured aqueous concentrations of the main glass components (B, Na, and Si) improved significantly upon addition of a time-dependent term, which therefore constitutes a simple representation of the glass-water reaction progress. Due to the limited changes in pH in the static dissolution tests, past a short initial period of rapid increase, addition of a pH-dependent term did not appreciably improve the fits, indicating that comprehensive model parameterization requires more than one type of glass corrosion test to capture a wide range of solution chemistries. IGCM parameters were found to be dependent on glass composition, and the parameter sets generated in this work will enable the development of composition–parameter correlation models that offer the promise of predicting IGCM parameters, and thus glass corrosion behavior, solely based on glass composition.

Hybrid inorganic–organic coatings enhancing glass corrosion resistance

This work aims to prepare a functional hybrid organic–inorganic coating on glass using the sol–gel process. The sol–gel coatings are commonly used for changing and/or enhancing optical, chemical and mechanical properties of the substrate glass. The coatings prepared in this work should exhibit high transmittance and good chemical resistance, whereof should be achieved by the combination of default precursor tetraethoxysilane (TEOS) and various functionalized silicon alkoxides 3-(trimethoxysilyl)propyl methacrylate (MEMO) and isobutyl(trimethoxy)silane (IBTMS). Sols were applied on substrate glass via the dip-coating method at different withdrawal speeds. Coatings were dried 1 h at 200 °C in ambient atmosphere. Assessment of transmittance was done by UV-Vis spectrophotometry, chemical resistance was observed by accelerated weathering tests in a humidity chamber, mechanical properties were evaluated with the means of standardized pencil hardness test and cross-cut tape test, and moreover analysis of abrasion resistance was done by model test. The most efficient functionalization was combination of 1% IBTMS + 1% MEMO and functionalization with MEMO up to 2% alone. These coatings showed good resistance against damp heat, they can withstand certain loads of abrasion and concurrently still exhibit high transmittance in the visible spectrum.Graphical

Non-destructive 3D exploration of silicate glass corrosion: a combined multiscale approach from the macro to the nanoscale.

In this research, a comprehensive multi-technique analysis, including synchrotron-based X-ray micro-computed tomography, is used to visualize the microstructure of alteration in a very particular Roman glass fragment, in which millennia of corrosion history have not significantly impacted the integrity of the fragment itself. This exceptionally rare occurrence has allowed for the maximization of meaningful data acquisition, by examining the alteration structures from the macro to the nanoscale. This study elucidates the intricate mechanisms underlying glass corrosion when in contact with soil, providing quantitative data and phase correlations in the alteration structures. These findings validate and refine existing predictive corrosion models.

The corrosion behavior of borosilicate glass in the presence of cementitious waste forms.

Borosilicate glasses are widely used for radioactive waste disposal due to their ability to incorporate a variety of contaminants and radionuclides while exhibiting high durability in various disposal scenarios. This research evaluated the dissolution of borosilicate glass using both single-pass-flow-through (ASTM C1662-18) and product consistency test (ASTM C1285-21) methods with different solutions, including a cementitious-contacted water (called grout-contacted, GC, from this point) and solutions with varying levels of dissolved cementitious species such as Si, Ca, Al. The results indicated that the presence of Ca plays a crucial role in suppressing glass corrosion, as evidenced by the slower normalized dissolution rates, which were one order of magnitude lower for boron and two orders of magnitude lower for rhenium, observed in both Ca-amended and GC solutions compared to the pH 12 buffer solution. This effect is attributed to the formation of a dense, low-porosity, and strongly bonded calcium silicate hydrate (CSH) layer on the glass surface, which implies that a glass corrosion process is influenced by ion exchange involving alkali ions Na+, K+, Ca2+, and hydrogen-containing species. A small number of glass particles treated in the GC solution showed minor corrosion pits in the form of shallow craters with an average diameter of approximately 500 μm. This observation is correlated with a significant reduction, 2000 to 3000 times lower, in the cumulative volume of glass pores, indicating that smaller pore voids were "sealed" in the presence of Ca2+ ions, likely attributed to the formation of CSH precipitation or other corrosion products such as calcium carbonate saturated from the grout solution. These findings suggest that the presence of dissolved Ca in the GC solution can slow down the dissolution of borosilicate glass, contrary to the expected trend of higher dissolution rates resulting from exposure to high alkaline and thus higher pH solutions.

Achieving superhydrophobicity of Zr-based metallic glass surface with anti-corrosion and anti-icing properties by nanosecond laser ablation and subsequent heat treatment

Water repellency of superhydrophobic surfaces offers an opportunity to enhance the corrosion and icing resistance of metallic glasses (MGs). Inspired by the “lotus effect” in nature, hierarchical micro/nanostructures were constructed on a Zr-based MG surface using nanosecond laser ablation. By subsequent heat treatment in air, the structured surface showed a water contact angle (CA) of 168.2 ± 1.5° and a sliding angle (SA) of 4 ± 0.7° (adhesion force of 9.8 ± 1.7 μN), exhibiting repellency and low adhesion to water. Specifically, the superhydrophobic surface stored in air and immersed in water possessed stability and durability, and the superhydrophobic surface still maintained superhydrophobicity after mechanical scratching. The heat treatment temperature worked as a switch for controlling the wettability transition, and by tuning the temperature, the structured surface can switch from superhydrophobicity (CA: 168.2 ± 1.5°) to superhydrophilicity (CA: ~0°). Furthermore, compared to the polished MG surface, the superhydrophobic surface increased the corrosion resistance and freezing time, and delayed the freezing temperature. This study provides a facile non-fluorinated method for fabricating superhydrophobic MG surfaces with anti-corrosion and anti-icing properties, which would enhance the application of MGs as structural and functional materials under extreme conditions.

Surface reaction, water diffusion and mechanical properties of hydrated nanoporous calcium aluminosilicate gel structures

A hydrated porous gel-like structure rich in silica is usually formed at the glass-water interface during the corrosion of silicate or borosilicate glasses. Understanding the chemical reactions and material transport in this amorphous interfacial layer is considered critical to design glasses with long term chemical durability for various technological applications. We have used large scale reactive molecular dynamics simulations with relaxation time up to 25 nano-seconds to generate hydrated nanoporous calcium aluminosilicate gel structures with different porosities and pore morphologies by using sequential hydration and hydrolysis reactions. The results provide insights into atomic and microstructures, surface and interfacial reactions, and mechanical properties of these gel structures that are difficult to directly access experimentally. It was found that the morphology and pore size distribution play a major role in the diffusion of water and mechanical strength in these gel structures, while the short-range structures of the gels are mainly controlled by the compositions of gel. The findings were compared and discussed with experimental observations.

Effects of Temperature and Relative Humidity on Crack Propagation Behavior During Wheel Scribing of Alkali-Free Glass Sheet

The effects of the ambient temperature and relative humidity on crack propagation behavior during wheel scribing were investigated. A chamber was built to allow dynamic observation of crack propagation behavior in a controlled atmosphere. A developed miniature scriber was installed in the chamber, and the crack propagation behavior was observed from lateral and back sides during wheel scribing under various atmospheric conditions. As a result, the median crack propagation rate increased with relative humidity. We speculated that this was caused by the stress corrosion of glass. Although stress corrosion is considered to be more reactive at higher temperatures, the results of scribing at different temperatures showed that higher temperatures did not necessarily increase median crack propagation. This is due to the formation of lateral cracks before the median cracks have fully propagated. These results suggest that the interaction between multiple cracks should be considered when discussing the effects of temperature and humidity in wheel scribing.

Surface Hardness and Abrasion Threshold of Chemically Strengthened Soda-Lime Silicate Glasses After Steam Processing

Chemical strengthening by diffusive ion exchange (IOX) is a common method to improve the mechanical performance of glass products. However, the process of ion-stuffing is often associated with an increase of surface hardness and a decrease of the resistance to abrasive wear during scratching, even when the thickness of the exchanged layer is low. Autoclave steam-treatment presents a way to compensate the enhanced surface brittleness accompanying IOX. It causes a notable shift in the load threshold for microabrasion to more abrasion-resistant glasses. Subject to the specific processing parameters, the softening effect is constrained to a surface layer of less than 500 nm in thickness; therefore, the overall compressive stress profile is not affected and the advantages of IOX strengthening are retained. In turn, ion-stuffing by IOX counteracts severe autoclave corrosion of soda-lime silicate glasses, making them suitable for a combination of both processes.

Study on surface modification and optical properties of Nd-doped phosphate glass

Using laser neodymium glass (N31) as the substrate, through ion exchange and hydrogen reduction process, a high-efficiency light absorption layer was formed from the substrate around the glass. It has been discovered that increasing the ion exchange temperature and time enhanced the exchange depth of laser glass, but excessive temperature and prolonged time will lead to corrosion of laser glass. The experiment shows that the best exchange temperature is 460°C and the best exchange time is 720min. When the hydrogen pressure was 0.8MP, the reduction temperature was 480°C and the reduction time was 12000 min, the absorption rate of the sample at 1053nm was 95.8%.

Corrosion of glaze in the marine environment: study on the green-glazed pottery from the Southern Song “Nanhai I” shipwreck (1127–1279 A.D.)

The “Nanhai I” shipwreck is an important discovery in the underwater archaeology of China, and many ceramics have been unearthed. These ceramics are important material artifacts of China’s “Maritime Silk Road” and have considerable significance for the study of foreign trade in the Southern Song Dynasty (1127–1279 A.D.). However, these ceramics have been buried in a marine environment for approximately 800 years and have all been corroded to varying degrees, with green-glazed pottery being the most severely corroded. In this study, the chemical compositions of five samples of green-glazed pottery and the corrosion morphology and mechanism of a representative sample were analyzed by optical microscopy, scanning electron microscopy-energy dispersive X‐ray spectrometry (SEM–EDS), Raman spectroscopy, and X-ray diffraction (XRD). Results: The green glaze is a low-temperature silica-aluminum oxide-lead oxide (SiO2-Al2O3-PbO) glaze with copper ions (Cu2+) as the main colorant. The corrosion morphology is characterized by alternating silicon (Si)- and lead (Pb)-rich layers, a sharp reaction interface between the Si-rich layer and the pristine glaze, and a relatively high porosity of the Si-rich gel layer, which is formed by the accumulation of spherical hydrated silica colloidal particles. These features suggest that the glaze was corroded through an interface-coupled dissolution–precipitation mechanism and that the properties of the gel pores controlled the reaction kinetics. Fluctuations in the solution properties at the reaction interface produced the complex morphology of the gel layer, whereas changes in the dryness and humidity of the environment are not essential factors. The samples have been corroding in the marine environment for nearly a thousand years, and explorations of the corrosion morphology and mechanism could provide reference information on the corrosion of various ancient ceramics and glasses and a basis for scientific conservation of these objects.