Definition - What does Dispersion mean?
Dispersion is a process in which a dry powder substance (or pigment) is mixed with a liquid such that all the individual molecules and particles of the dry powder become separated from each other and are evenly distributed and completely mixed in the liquid medium.
Corrosionpedia explains Dispersion
The dispersion process is the complete mixing of one substance into other liquid substance and later using this dissolved solution for industrial purposes, such as protecting materials from failures. The failures could be material fatigue failure, corrosion or rusting.
Apart from protecting materials from failures, dispersed solutions are widely used for various industrial purposes such as:
- Dyeing and tanning.
- Manufacturing synthetic rubber and plastics.
- Preparation of cosmetics such as shampoos, salves and therapeutic products.
Two examples of dispersion are emulsion and atomized powder.
An emulsion is a suspension of tiny droplets of one liquid in a second liquid, such as an oil-in-water emulsion. An emulsion is thicker (has a higher viscosity) than either oil or water. The term emulsion is often applied to mixed systems that should be characterized as solutions, suspensions or gels. For example, so-called photographic emulsion is actually a gelatin gel in which tiny silver bromide crystals are dispersed.
Similarly, atomized powder is a powder produced by the dispersion of a molten material into particles by a rapidly moving gas or liquid stream or by mechanical dispersion.
Atomization is the dominant method for producing metal and pre-alloyed powders from:
- Low-alloy steels
- Stainless steels
- Tool steels
Advantages of atomized powders include:
- Longer useful life and reduced lifecycle costs.
- Greater wear resistance.
- Superior high-temperature properties.
- Increased design flexibility.
- Improved machinability.