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Calculate the number of atoms in a critically sized nucleus for the homogeneous nucleation of pure iron.
The number of atoms in a critically sized nucleus for the homogeneous nucleation of pure iron.
Answer to Problem 35AAP
The number of atoms in a critically sized nucleus for the homogeneous nucleation of pure iron is
Explanation of Solution
Express the volume of critical size nucleus.
Here, critical radius is
Since pure iron has a BCC structure, each unit cell has 2 atoms.
Express the volume of pure iron.
Here, side of a BCC unit cell is
Express the volume per atom.
Here, number of atoms per BCC unit cell is
Express the number of atoms in a critically sized nucleus for the homogeneous nucleation of pure iron.
Conclusion:
For pure iron, write the critical radius as:
Write the side of a BCC unit cell.
Substitute
Substitute
Substitute
Substitute
Hence, the number of atoms in a critically sized nucleus for the homogeneous nucleation of pure iron is
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Chapter 4 Solutions
Foundations of Materials Science and Engineering
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