Material Structure Flashcards
What is a crystalline material structure?
Regular arrangement of atoms.
What is an amorphous material structure?
Non regular arrangement of atoms.
What is a semi crystalline material structure?
Material with both crystalline and amorphous regions.
What is the difference between a single crystal and a polycrystalline material structure.
Single Crystal: The whole material has one arrangement of atoms.
Polycrystalline: The material has multiple crystal regions oriented at random to one and other.
What is a unit cell?
The smallest segment of a structure that can be repeated.
What is a polymorphic material?
A material that can adopt more than one material structure.
What is an allotropic material?
A material that has different crystal structures at different temperatures.
What are 3 defects in material structures?
- grain boundaries not matching
- vacancies
- dislocations
What is a grain boundary defect?
Grain boundaries in structure not aligning leaving space.
Describe vacancy material defect.
Missing atoms in material structure leaving gaps.
Describe dislocation defect.
Caused by an extra incomplete row in a crystal structure.
What is elastic deformation?
When a material is deformed but return to original shape. This only causes the bonds in material to stretch.
What is plastic deformation?
When a material is deformed permanently, breaking bonds.
What material property does dislocation slip enable?
Ductility.
In metals, dislocation slip is easy meaning the metal is _____ ?
Ductile.
