Specific strength of materials is very high when they are in fibre size but lower when they are in bar form Why ?

Specific strength of materials is very high when they are in fibre size but lower when they are in bar form Why ?
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1 Answer

Answer :

Crystal structure has ordered, repeating arrangement of atoms. Fibres are liable to maintain this and
thus have high specific strength. As size increases, the condition of ordered and repeating arrangements
can’t be guaranteed because of several types of defects and dislocations and thus the specific strength
gets lower.
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