According to Rheology Solutions, shrinkage is the process or result of becoming less or smaller. Expansion is often caused by heat that is applied to a body, increasing the rate of vibration and the distance between the molecules and, hence, the space occupied by the body, that is, its volume increases.
This increase in volume is not constant for all substances for any given rise in temperature, but is a specific property of each kind of substance.
The Schleibinger Shrinkage/Expansion Unit is designed to measure the shrinkage or expansion of fluid building materials and also unstressed deformation of the sample. Measuring these properties is critical for proper design and construction using a variety of materials any of which may experience either shrinkage or expansion.