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ANALISIS SEL SATUAN
Sel satuan (unit cell)
susunan atom yang terkecil di dalam ruang dan berulang secara periodik
Logam
kubus, heksagonal, dan tetragonal
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STRUKTUR KRISTAL
Karakteristik penting dalam struktur kristal:
1. Bilangan koordinasi
Jumlah atom terdekat yang mengelilingi atom lainnya
2. Atomic Packing Factor (APF)
Sel satuan struktur kristal
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STRUKTUR KRISTAL
Karakteristik penting dalam struktur kristal:
3. Bidang Slip (slip plane)
Bidang yang memiliki jumlah atom yang lebih banyak atau bidang yang yang memiliki susunan atom paling rapat
Fungsi bidang slip tempat bergeser/berpindahnya atom-atom
Dasar “ teori pembentukan logam”
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A Unit Cell
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Jenis Sel Satuan
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Jenis Sel Satuan
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(c) 2003 Brooks/Cole Publishing / Thomson Learning™
The fourteen
types of Bravais
lattices grouped
in seven crystal
systems.
(c) 2003 Brooks/Cole Publishing / Thomson Learning™
Definition of the
lattice parameters
and their use in
cubic,
orthorhombic, and
hexagonal crystal
systems.
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Sel Satuan Pada Logam
a. Kubus pusat badan (body center cubic = bcc)
b. Kubus pusat muka (face center cubic = fcc)
c. Heksagonal susunan rapat (close packed hexagonal= cph)
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A. Kubus sederhana (simple cubic /sc)
B. Kubus pusat badan (body center cubic /bcc)
C. Kubus pusat muka (face center cubic / fcc)
KUBUS
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(a) Illustration
showing sharing of
face and corner
atoms. (b) The
models for simple
cubic (SC), body
centered cubic
(BCC), and face-
centered cubic
(FCC) unit cells,
assuming only one
atom per lattice
point.
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Illustration of coordinations in (a) SC and (b) BCC unit cells. Six atoms touch
each atom in SC, while the eight atoms touch each atom in the BCC unit cell.
Bilangan Koordinasi
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