Page 26 - Materials Science and Engineering An Introduction
P. 26
xxii • List of Symbols
(hkil) = Miller indices for a crystal- r = reaction rate (17.3)
lographic plane, hexagonal r A , r C = anion and cation ionic radii
crystals (3.10) (12.2)
I = electric current (18.2) S = fatigue stress amplitude (8.8)
I = intensity of electromagnetic SEM = scanning electron microscopy
radiation (21.3) or microscope
i = current density (17.3) T = temperature
i C = corrosion current density (17.4) T c = Curie temperature (20.6)
J = diffusion flux (5.3) T C = superconducting critical
J = electric current density (18.3) temperature (20.12)
K c = fracture toughness (8.5) T g = glass transition temperature
K Ic = plane strain fracture tough- (13.10, 15.12)
ness for mode I crack surface T m = melting temperature
displacement (8.5) TEM = transmission electron
k = Boltzmann’s constant (4.2) microscopy or microscope
k = thermal conductivity (19.4) TS = tensile strength (6.6)
l = length t = time
l c = critical fiber length (16.4) t r = rupture lifetime (8.12)
ln = natural logarithm U r = modulus of resilience (6.6)
log = logarithm taken to base 10 [uyw] = indices for a crystallographic
M = magnetization (20.2) direction (3.9)
M n = polymer number-average [uvtw], [UVW] = indices for a crystallographic
molecular weight (14.5) direction, hexagonal crystals
M w = polymer weight-average (3.9)
molecular weight (14.5) V = electrical potential difference
mol% = mole percent (voltage) (17.2, 18.2)
N = number of fatigue cycles (8.8) V C = unit cell volume (3.4)
N A = Avogadro’s number (3.5) V C = corrosion potential (17.4)
N f = fatigue life (8.8) V H = Hall voltage (18.14)
n = principal quantum number (2.3) V i = volume fraction of phase i (9.8)
n = number of atoms per unit cell y = velocity
(3.5) vol% = volume percent
n = strain-hardening exponent (6.7) W i = mass fraction of phase i (9.8)
n = number of electrons in an wt% = weight percent (4.4)
electrochemical reaction (17.2) x = length
n = number of conducting elec- x = space coordinate
trons per cubic meter (18.7) Y = dimensionless parameter or
n = index of refraction (21.5) function in fracture toughness
n¿ = for ceramics, the number of expression (8.5)
formula units per unit cell y = space coordinate
(12.2) z = space coordinate
n i = intrinsic carrier (electron and a = lattice parameter: unit cell y–z
hole) concentration (18.10) interaxial angle (3.7)
P = dielectric polarization (18.19) a, b, g = phase designations
P–B ratio = Pilling–Bedworth ratio (17.10) a l = linear coefficient of thermal
p = number of holes per cubic expansion (19.3)
meter (18.10) b = lattice parameter: unit cell x–z
Q = activation energy interaxial angle (3.7)
Q = magnitude of charge stored g = lattice parameter: unit cell x–y
(18.18) interaxial angle (3.7)
R = atomic radius (3.4) g = shear strain (6.2)
R = gas constant ¢ = precedes the symbol of a pa-
%RA = ductility, in percent reduction rameter to denote finite change
in area (6.6) P = engineering strain (6.2)
r = interatomic distance (2.5) P = dielectric permittivity (18.18)
