Metal Defects (Leaving Cert Engineering): Quizzes
📚Quizzes
Practise the questions
12 questions from this quiz
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Practise the questions
12 questions from this quiz
What are line defects in crystalline materials?
What are line defects in crystalline materials?
Structural imperfections along a line
In how many dimensions do line defects extend through a material?
In how many dimensions do line defects extend through a material?
One dimension
What is the most common type of line defect found in crystalline materials?
What is the most common type of line defect found in crystalline materials?
Dislocation
What structural feature defines a dislocation?
What structural feature defines a dislocation?
An incomplete row of atoms
What type of stress causes dislocations to become mobile?
What type of stress causes dislocations to become mobile?
Shear stress
What is shear stress?
What is shear stress?
Forces sliding one part past another
Where do dislocations travel as they move through a material?
Where do dislocations travel as they move through a material?
From interior towards surface
What does a dislocation's incomplete row of atoms create in the material?
What does a dislocation's incomplete row of atoms create in the material?
Areas of high stress
What typically forms when a dislocation reaches the surface of a material?
What typically forms when a dislocation reaches the surface of a material?
Starting point for a crack
How does the energy needed to move a dislocation compare to deforming a perfect crystal?
How does the energy needed to move a dislocation compare to deforming a perfect crystal?
Less energy is required
Why do dislocations represent the easiest path for atomic rearrangement?
Why do dislocations represent the easiest path for atomic rearrangement?
Less energy needed for movement
What is the common failure progression in metals involving dislocations?
What is the common failure progression in metals involving dislocations?
Internal dislocation to crack to failure