Driving Force
The boundary between one grain and its neighbour is a defect in the crystal structure and so it is associated with a certain amount of energy. As a result there is a thermodynamic driving force for the total area of boundary to be reduced. If the grain size increases, accompanied by a reduction in the actual number of grains, then the total area of boundary will be reduced.
In comparison to phase transformations the energy available to drive grain growth is very low and so it tends to occur at much slower rates and is easily slowed by particles or solute atoms.
Read more about this topic: Grain Growth
Famous quotes containing the words driving force, driving and/or force:
“Decisive inventions and discoveries always are initiated by an intellectual or moral stimulus as their actual motivating force, but, usually, the final impetus to human action is given by material impulses ... merchants stood as a driving force behind the heroes of the age of discovery; this first heroic impulse to conquer the world emanated from very mortal forcesin the beginning, there was spice.”
—Stefan Zweig (18811942)
“Most of the rules and precepts of the world take this course of pushing us out of ourselves and driving us into the market place, for the benefit of public society.”
—Michel de Montaigne (15331592)
“In Arms not worse, in foresight much advanct,
We may with more successful hope resolve
To wage by force or guile eternal Warr
Irreconcileable, to our grand Foe,”
—John Milton (16081674)