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BASIC ENGINEERING
MATERIAL ED8E 11 | | |
 Rigidity
This is a measure of a materials ability not to deflect under an applied load (stiffness). For Example
although
steel is very much stronger than cast iron the latter material is preferred for machine beds and frames
because
it is more rigid and less likely to deflect with consequent loss of alignment and accuracy.
For a given load the cast iron bar deflects less than the steel bar because cast iron is a more rigid
material .
However, when the load is increased the cast iron bar will break, whilst the steel bar under the same
load
merely deflects a little further but does not break . Thus a materials which is rigid is not necessarily
strong . In
fact more often than not rigid materials are found to be brittle. click here for a simple explanation
and picture
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