Corrosion glasses

XPS has been used in almost every area in which the properties of surfaces are important. The most prominent areas can be deduced from conferences on surface analysis, especially from ECASIA, which is held every two years. These areas are adhesion, biomaterials, catalysis, ceramics and glasses, corrosion, environmental problems, magnetic materials, metals, micro- and optoelectronics, nanomaterials, polymers and composite materials, superconductors, thin films and coatings, and tribology and wear. The contributions to these conferences are also representative of actual surface-analytical problems and studies [2.33 a,b]. A few examples from the areas mentioned above are given below more comprehensive discussions of the applications of XPS are given elsewhere [1.1,1.3-1.9, 2.34—2.39]. 

Over recent years, a number of new applications of glasses have grown out of increased understanding and control of glass corrosion behaviour. 

Hench, L.L. (1975). Characterization of glass corrosion and durability. Journal of Non-Crystalline Solids 19 27-39. 

Sanders, D.M., Person, W.B. and Hench, L.L. (1972). New methods for studying glass corrosion kinetics. Applied Spectroscopy 26 530-536. 

Atassi 1989 Dran et al. 1989 Petit et al. 1990 Advocat 1991 Grambow 1991 Clark Zoitos 1992 Cunnane et al. 1993 Bates et al. 1994, 1996 Clark et al. 1994 Cunnane Allison 1994 Ebert Mazer 1994 Feng et al. 1994 Ewing 1996). On the basis of extensive work on the behaviour of HLW glasses, glass corrosion exhibits a sequence of the following three reactions (see Fig. 7) ... 

Adams, P. B. 1984. Glass corrosion A record of the past A predictor of the future Journal of Non-Crystalline Solids, 67, 193-205. 

Grambow, B. 1985. A general rate equation for nuclear waste glass corrosion. In Jantzen, C. M., Stone, J. A. Ewing, R. C. (eds) Scientific Basis for Nuclear Waste Management VIII. Materials Research Society Symposia Proceedings, 44, 16-27. 

Vernaz, E. Dussosoy, J.-L. 1992. Current state knowledge of nuclear waste glass corrosion mechanisms The case of R7T7 glass. Applied Geochemistry (Supplement Issue), 1, 13-22. 

Towards a consistent rate law glass corrosion kinetics near saturation... 

This burgeoning set of reviews serves as a starting point for our discussion of glass corrosion resistance, although our review differs from those noted above by emphasizing dissolution behaviour near saturation with respect to potential rate-limiting phases. 

There are a number of mechanisms that pose potential problems to predicting dissolution rate kinetics as the system approaches saturation. Part of this conundrum originates from current models of glass corrosion kinetics that cannot yet incorporate these unanticipated phenomena into a mathematical equation that is consistent with the constraints of thermodynamics or kinetics. These phenomena include (1) alkali-hydrogen exchange (2) dissimilar reactivity of... 

Grambow, who perhaps wrote the most commonly referenced paper in the glass corrosion... 

The failure of models based on application of TST rate laws to glass/water systems does not mean, however, that diffusion through a leach layer is by default the answer to this dilemma. Clearly, the set of recently reported data on glass corrosion resistance shows that it is not an either-or situation between affinity- and diffusion-based rate laws. Finding a mathematically stable form of the rate equation appears to be more worthy of pursuit. 

Bourcier, W. L. 1994. Waste glass corrosion modeling Comparison with experimental results. Materials Research Society Symposium Proceedings, 333, 69 - 82. 

Grambow, B. 1985. A general rate equation for nuclear waste glass corrosion. Materials Research Society Symposium Proceedings, 44, 15-27. 

Kinetics of Ceramic and Glass Corrosion by Gases. The attack of ceramics and glasses by gaseous reactants is much more prevalent than corrosion due to liquids. In addition to the chemical composition of the attacking medium, the geometry of the ceramic solid is of tantamount importance to its corrosion resistance. That is, a... 

Figure 3. Experimental arrangements for studying glass corrosion. Conditions (a,b) ASTM, T = 121°C-autoclave, t = I h (c) IAEA, T = 25°C, t = variable (d) ISO, T = variable, t = variable (e) Soxhlet, T 100°C, t = variable and (f) T = 25-95°C, t = variable. (Reproduced, with permission, from Ref. 1. Copyright 1980, North-Holland Publishing Co.)...

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