| About this Abstract |
| Meeting |
MS&T24: Materials Science & Technology
|
| Symposium
|
Glasses and Optical Materials: Current Issues and Functional Applications
|
| Presentation Title |
Structural Relaxation of a Medieval Cathedral Glass |
| Author(s) |
Ricardo Felipe Lancelotti, Marcelo Kurtovic, Oscar Peitl, Edgar Zanotto |
| On-Site Speaker (Planned) |
Ricardo Felipe Lancelotti |
| Abstract Scope |
Glass is thermodynamically unstable material that spontaneously relaxes toward the liquid state. There is an urban legend about the apparent flow of glass in medieval cathedral windows at room temperature. Approximate calculations have shown that the time required for window glass to flow at room temperature is absurdly high, with variations in thickness caused by methods of manufacture. It is necessary to extrapolate the viscosity value of the material to room temperature to perform these calculations. Recent works showed that the experimental values of the relaxation times are close to those calculated using the equilibrium viscosity. In this work, we obtained a glass with a medieval composition, characterized it and measured the properties at temperatures close to the glass transition, and then revisited the calculations by testing all the equations. We recalculated with greater precision the time required for a medieval cathedral glass to flow at some temperatures, including ambient. |