Similarities and Difference Between the FCC and HCP Structure
Page 1 of 1
Similarities and Difference Between the FCC and HCP Structure
The face centered cubic and hexagonal close packed structures both have a packing factor of 0.74, consist of closely packed planes of atoms, and have a coordination number of 12. The difference between the fcc and hcp is the stacking sequence. The hcp layers cycle among the two equivalent shifted positions whereas the fcc layers cycle between three positions. As can be seen in the image, the hcp structure contains only two types of planes with an alternating ABAB arrangement. Notice how the atoms of the third plane are in exactly the same position as the atoms in the first plane. However, the fcc structure contains three types of planes with a ABCABC arrangement. Notice how the atoms in rows A and C are no longer aligned. Remember that cubic lattice structures allow slippage to occur more easily than non-cubic lattices, so hcp metals are not as ductile as the fcc metals.
The table below shows the stable room temperature crystal structures for several elemental metals.
To see the table clik on the link below :
[You must be registered and logged in to see this link.]
Similar topics
» First Principles Studies on the Electronic Structure and Band Structure of Paraelectric SrTiO3 by Different Approximations
» Temperature-Induced Phase Transition of In2O3 from a Rhombohedral Structure to a Body-Centered Cubic Structure
» Crystal Structure of Magnetite Fe3O4 ( spinel structure )
» Antiferromagnetic structure of NiO in rhombohedral structure
» Antiferromagnetic structure of NiO
» Temperature-Induced Phase Transition of In2O3 from a Rhombohedral Structure to a Body-Centered Cubic Structure
» Crystal Structure of Magnetite Fe3O4 ( spinel structure )
» Antiferromagnetic structure of NiO in rhombohedral structure
» Antiferromagnetic structure of NiO
Page 1 of 1
Permissions in this forum:
You cannot reply to topics in this forum
|
|