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| Failure Mechanisms | |||||||||||||||||||
| Polymers
· In
Polymeric samples, macromolecules
can span the fracture crack forming a "Craze." These molecules are pulled
from the bulk polymer on either side
of the crack surface as illustrated.
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| From:
Courtney, "Mechanical Behavior of Materials,"
McGraw Hill (1990) |
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| · The craze has a large void volume, making the craze a region of low density. Crack tip stress concentration causes the craze region to propagate normal to the maximum tensile stress direction. | |||||||||||||||||||