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Failure
Mechanisms |
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·
In
addition to this Mode I brittle fracture, brittle fracture that has some
microscopic plastic deformation as a precursor to crack propagation can
also occur (Mode II). This is illustrated below. |
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·
Plastic
deformation within a grain leads to crack creation through dislocation
pile-up. These cracks can cleave the grain giving intragranular brittle
fracture.
· Grain
boundary separation during the microscopic plastic deformation process
gives rise to cracks that can propagate in an intergranular brittle fracture
mode.
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From:
Courtney, "Mechanical Behavior of Materials," McGraw Hill (1990) |
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