| 1. |
- Jonson, Bo, et al.
(författare)
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Devitrification and dilatometric properties of low Tg unleaded silicate glasses
- 2013
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Ingår i: Glass Technology: European Journal of Glass Science and Technology Part A. - 1753-3554 .- 1753-3546. ; 54:3, s. 108-110
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Tidskriftsartikel (refereegranskat)abstract
- Candidate lead free glass enamels have been sought within the glass system described in general terms by the mole fractions 0·25R 2O.0·16(R'O, R2"O3). 0·59SiO2 where R=Li, Na, K; R'=Ba, Zn and R"=B, Bi. Glass compositions containing high mole fractions of Li2O were found to devitrify when they were heated to temperatures up to 530°C typical for the procedure used when fusing enamels to tableware glasses. The devitrification characteristics are complex and several peaks atributed to crystallisation were found by DSC characterisation. The thermal expansion coefficient(α) within the system ranges from 11-14×10-6 K-1 and the glass transition temperatures(Tg) between 410-460°C. The measured data could be fitted to the chemical composition by multiple regression analysis with a general equation of the form:(α, Tg)=K(α/T g)+Σ(cR×fR) in which K is a constant, c is the oxide mole fraction and f is an oxide specific factor. The statistical analysis correlation coefficients(r2) were around 0·9.
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| 2. |
- Karlsson, Stefan, 1984-, et al.
(författare)
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Surface ruby colouring of float glass by sodium-copper ion exchange
- 2013
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Ingår i: Glass Technology: European Journal of Glass Science and Technology Part A. - : Society of Glass Technology. - 1753-3554 .- 1753-3546. ; 54:3, s. 100-107
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, colouration of the tin side of commercial soda-lime-silica float glass by copper ion exchange is described and characterised. Data on the resulting concentration versus depth profiles, absorbance versus depth profiles, UV-Vis spectra and CIE-Lab colour coordinates are reported. Fundamental aspects of the process of colouration are described and discussed. Optimum saturation of the colour is achieved after ion exchange at 520°C for 10 h or at 500°C for 20 h. The depth of the coloured layer increases with increasing treatment time. At the same time, a linear dependency is found between the values of a and b in the CIE-Lab colour space for variations of treatment time and temperature. The later indicates broad tunability of colouration between different shades of ruby and varying colour saturation. It is shown that colour arises from a redox reaction between copper species and residual tin ions, and that the depth of the coloured layer is governed by the position of the tin hump. The critical concentration of tin and copper to achieve colour formation was found to be ∼0·25 mol% and >1 mol%, respectively.
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| 3. |
- Karlsson, Stefan, 1984-, et al.
(författare)
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The effect of single-side ion exchange on the flexural strength of plain and holed float glass containing a drilled hole
- 2013
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Ingår i: European Journal of Glass Science and Technology. Part A: Glass Technology. - 1753-3546. ; 54:2, s. 66-71
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Tidskriftsartikel (refereegranskat)abstract
- The effect of single-side ion exchange (using a KNO3:KCl mixture) on the ring-on-ring flexural strength of float glass has been studied. Two ion exchanged series, treated at 450 and 515°C, were investigated. The ion exchanged samples showed approximately 160 respectively 100% increases in their arithmetic mean strength compared to as-received float glass. Furthermore, a series of samples containing drilled holes were studied in order to investigate the effect of single-side ion exchange on such common construction elements. The samples that contained drilled holes were ion exchanged at 450°C and showed around 140% increase of the fracture load compared to the untreated samples containing drilled holes. As a general observation, the ion exchange treatment induced ~110 MPa compressive stresses (515°C) and ~180 MPa compressive stresses (450°C). The ion exchanged samples showed no significant increase in stiffness.
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