Unformatted text preview: g patt
that is located in the interstices of the structure under
on which atoms or ions are placed to form a crystal.
consideration. Interstitials may be either the same or a
different species than the solvent.
lattice point One position in the three-dimensional
space-ﬁlling repeating pattern that forms a crystal. One
interstitial solid solution A solid solution in which
more atoms or ions are placed at each lattice point.
atoms or ions of a foreign species are located in the
lever rule An equation that enables one to calculate
intrinsic conduction Electrical conduction in pure
relative amounts of two phases present in a two-phase
semiconductors such as Force Ge, and GaAs.
mixture in terms of the compositions of the alloy and t
Fc = Ff = Fm
invariant reaction A reaction is which there are zero
degrees of freedom.
line compound A compound whose composition is
independent of temperature.
ion implantation A process in which ions of light
elements such as boron and nitrogen are made to impinge
linear density The number of atoms centered on a
on the surface of the workpiece at a high velocity. The
crystallographic direction per unit length.
assume for simplicity that the constituent materials are isotropic. This assumption is
surface hardens due to penetration of the ions.
liquid crystal An anisotropic ﬂuid, usually a melt or
reasonable except when organic ﬁbers are used.
ionic bond Asubjected to an axial force Fc , involving Figure 14.5–2a, the total
If the composite is type of primary bond as shown in
solution characterized by molecular alignment.
force is partitioned into two parts, Ff (force on the ﬁbers) and Fm (force on the matrix).
electronegative and electropositive atoms that display a
liquid metal embrittlement A degradation mechani
We may write,
signiﬁcant difference in their electronegativity values
in which a liquid metal preferentially attacks the grain
(usually EN Fm 1.7).
boundaries in a solid.
Noting that F
A Equation 14.5–3 The written as:
ionic (atomic) ,polarization can be temporary displaceliquidus The temperature at which a liquid begins to
c positive and Am
m negative ions in the presence of an
ment of Ac
freeze during equilibrium cooling conditions.
electric f , and
where c , ﬁeld. m are the average normal stresses on the composite, ﬁbers, and matrix
long-range order Existence of a regular repeating
and Ac , Af , and Am are the corresponding cross-sectional areas. Dividing both sides of
ionization potential The energy required to remove an
Equation 14.5–4 by Ac yields:
arrangement of atoms, ions, or molecules within a
electron from an isolated neutral atom.
crystalline region of a material.
isomorphousAc Having cthe same structure. When applied (14.5–5)
luminescence Absorption of light or electromagnetic
to a phase diagram, indicating that the solid phase has
Since for continuous-ﬁber composites the ﬁber and matrix area fractions are the same as
radiation at high frequencies with subsequent reradiatio
the same structure fractions i...
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