Characteristics of a Strong Material
Date: Summer 2009
What are the characteristics of a strong metal? ceramic? polymer?
Unfortunately, when it comes to materials the term "strong" has many
different meanings. For example, very hard, tempered steel will
resist deformation (changing shape) and this is considered strong.
However, despite being strong, some tempered steel can be brittle
and if hit with enough force, fast enough, it will shatter -
however, it is still considered a strong material. In contrast,
cross-linked, vulcanized rubber will deform readily (it bends or
compresses with even low force), but if we try to stretch it, it
takes a lot of force before it finally breaks. So, even though
rubber yields with an application of tensile stretching force, since
it does not break or tear apart readily, it is also considered strong.
The upshot of this is that the molecular source for the strength of
these materials vary depending on the material. In general, how well
the atoms hold on to each other -either by intermolecular attraction
or by interatomic bonds- is a good guide of how strong materials
are. This is mitigated by crystal boundary forces, intermolecular
physical loops, etc.
Perhaps, if you could let us know what precisely you mean by
"strength" and for what specific type of material, we can answer this better.
Greg (Roberto Gregorius)
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Update: June 2012