ISSN:
1551-2916
Source:
Blackwell Publishing Journal Backfiles 1879-2005
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
Density and microstructural evolution of porcelains containing 0–25 wt% soda–lime–silica (SLS) waste glass fired over a range of temperatures from 600° to 1400°C have been investigated. After firing 3 h at 1100°C, batches containing 6.25 wt% SLS glass and 18.75 wt% nepheline syenite flux system attained open-pore closure and a bulk density of 2.40 g/cm3, comparable to results from commercial porcelain after firing at 1200°C. SLS glass softens and melts, conferring early densification and overfiring on porcelains fired at normal commercial firing temperatures. The microstructural evolution examined using XRD, SEM/energy dispersive spectroscopy (EDS), and TEM/EDS revealed formation of a variable composition plagioclase, rounded wollastonite particles, sodium silicates, and tridymite in batches containing SLS glass, in addition to primary and secondary mullites, partially dissolved quartz, and a glassy matrix as found in the waste-free batch. Ca2+ and Na+ from the SLS glass migrate to regions containing the products of clay decomposition to form plagioclase, limiting the extent of mullite crystallization. The presence of a solution rim surrounding quartz and different glass compositions around wollastonite crystals indicate that the system is not in equilibrium, although phases predicted by the Na2O–CaO–SiO2 equilibrium diagram were formed.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1111/j.1551-2916.2005.00292.x
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