DIL L75 VS – Glass rod – Thermal expansion
Glass sample – Thermal expansion / softening point / glass point
Glasses represent a distinctive class of materials, predominantly existing in an amorphous solid state, signifying a non-crystalline structure. Despite their lack of a crystalline arrangement, they are not in a liquid state either, as their molecules maintain a fixed yet non-crystalline structure.
This amorphous nature imparts unique properties to glasses, such as transparency and a notably low degree of thermal expansion, characterized by a low coefficient of thermal expansion (CTE). Contrary to the intuitive assumption that their amorphous composition might imply a low melting point, glasses exhibit resilience in their mechanical properties even at elevated temperatures, rendering them valuable as construction materials throughout human history.
In the contemporary landscape, a diverse array of specialized glasses is available, each tailored to deliver distinct properties for specific applications. Understanding the precise behavior of each type is crucial.
For instance, a glass rod sample was subjected to pushrod dilatometry. The observed linear expansion persists until approximately 575°C, after which there is a sudden surge in expansion. This phenomenon is a characteristic pattern exhibited by many glass samples. Prior to reaching the maximum expansion, just before the onset of melting, a distinctive change in the expansion rate occurs, marking the glass transition or glass point. Subsequently, as the expansion reaches its peak, the glass enters a softened or molten state, defining the maximum as the softening or melting point.
Related instruments
DIL L75 PT Vertical
- Vertical “Zero-Friction” Dilatometer
- Multi furnace option (up to 3 furnaces)