Rheology is the study of deformation and flow of matter, which describes the interaction between force, time and deformation. The term rheology comes from the Greek words ‘rheo’ and ‘logia,’ which mean ‘flow’ and ‘the study of’, respectively.
As is clear from the definition, rheology not only deals with the flow of liquid-like materials but also the deformation of solid-like materials, especially the behavior of viscoelastic materials that exhibit the properties of both solids and liquids in response to force, time and deformation.
The technique employed to evaluate the rheological properties of a material is known as rheometry. The flow properties and viscoelastic properties of a material can be determined by various rheometric tests using a rheometer. However, it is usually better and easier to deal with these two properties separately.
Flow and viscosity will be the focus of the first part of this article. The various tests that can be employed to measure and explain the flow behavior of simple and complex fluids will also be discussed here. The second part will focus on deformation and viscoelasticity.
Topics Covered
- Viscosity
- Shear Flow
- Shear Thinning
- Shear Thickening
- Thixotropy
- Yield Stress
- Viscoelasticity
- Elastic Behavior
- Viscous Behavior
- Viscoelastic Behavior
- Creep Testing
- Small Amplitude Oscillatory Testing
- Linear Viscoelastic Region (LVER)
- Oscillatory Frequency Sweep
- The Viscoelastic Spectrum
This information has been sourced, reviewed and adapted from materials provided by Malvern Panalytical.
For more information on this source, please visit Malvern Panalytical.