496T fm i-xxvi 01/11/060: 06 Page xxiv xx· List of Symbols HRISN, HR45W= superficial Rockwell n= number of conducting hardness: 15N and 45W electrons pe I cubIc meter(18.7) iV= Vickers hardness(6.10) n= index of refraction(21.5 h= Planck's constant(21.2) for ceramics the number (hkl)= Miller indices for a of formula units per unit crystallographic plane(3.10) cell(12.2) I= electric current (18.2) n;=intrinsic carrier(electron and ntensity of electromagnetic hole) concentration(1810) radiation(21.3) P= dielectric polarization(18.19) i= current density(17.3) P-B ratio= Pilling-Bedworth ratio(17.10) ic=corrosion current density p= number of holes per cubic (174) meter(18.10) J= diffusion flux (5.3) Q= activation energy J= electric current density(18.3) Q= magnitude of charge stored fracture toughness(8.5) plane strain fractur R=atomic radius(3. 4) toughness for mode I R= gas constant crack surface displacement PoRa= ductility, in percent reduction (8.5) in area(6.6) k= Boltzmanns constant(4.2) r= interatomic distance(2.5) k= thermal conductivity (19.4) r= reaction rate(17.3) I= length TA, rc= anion and cation ionic radii lc= critical fiber length(16.4) In natural logarithm S=fatigue stress amplitude(8. 8) log= logarithm taken to base 10 SEM scanning electron M= magnetization(20.2) microscopy or microscope M,= polymer number-average temperature molecular weight(14.5) T= Curie temperature(20.6) Mu= polymer weight-average Tc= superconducting critical tem- molecular weight (14.5) perature(20.12) mol%= mole percent Tg= glass transition temperature N= number of fatigue cycles(8.8) (139,15.12) A= Avogadro's number( 3.5) Im= melting temperature s= fatigue life( 8.8) TEM transmission electron microscopy or microscope n= principal quantum number TS =tensile strength(6.6) n= number of atoms per unit cell (3.5) tr= rupture lifetime(8.12) strain-hardening exponent U,= modulus of resilience(6.6) (6.7) uww= indices for a crystallographic n= number of electrons in direction(3.9) an electrochemical V= electrical potential difference reaction(17. 2) ( voltage)(172,18.2)xxiv • List of Symbols HR15N, HR45W superficial Rockwell hardness: 15N and 45W scales (6.10) HV Vickers hardness (6.10) h Planck’s constant (21.2) (hkl) Miller indices for a crystallographic plane (3.10) I electric current (18.2) I intensity of electromagnetic radiation (21.3) i current density (17.3) iC corrosion current density (17.4) J diffusion flux (5.3) J electric current density (18.3) Kc fracture toughness (8.5) KIc plane strain fracture toughness for mode I crack surface displacement (8.5) k Boltzmann’s constant (4.2) k thermal conductivity (19.4) l length lc critical fiber length (16.4) ln natural logarithm log logarithm taken to base 10 M magnetization (20.2) polymer number-average molecular weight (14.5) polymer weight-average molecular weight (14.5) mol% mole percent N number of fatigue cycles (8.8) NA Avogadro’s number (3.5) Nf fatigue life (8.8) n principal quantum number (2.3) n number of atoms per unit cell (3.5) n strain-hardening exponent (6.7) n number of electrons in an electrochemical reaction (17.2) Mw Mn n number of conducting electrons per cubic meter (18.7) n index of refraction (21.5) n for ceramics, the number of formula units per unit cell (12.2) ni intrinsic carrier (electron and hole) concentration (18.10) P dielectric polarization (18.19) P–B ratio Pilling–Bedworth ratio (17.10) p number of holes per cubic meter (18.10) Q activation energy Q magnitude of charge stored (18.18) R atomic radius (3.4) R gas constant %RA ductility, in percent reduction in area (6.6) r interatomic distance (2.5) r reaction rate (17.3) rA, rC anion and cation ionic radii (12.2) S fatigue stress amplitude (8.8) SEM scanning electron microscopy or microscope T temperature Tc Curie temperature (20.6) TC superconducting critical tem￾perature (20.12) Tg glass transition temperature (13.9, 15.12) Tm melting temperature TEM transmission electron microscopy or microscope TS tensile strength (6.6) t time tr rupture lifetime (8.12) Ur modulus of resilience (6.6) [uvw] indices for a crystallographic direction (3.9) V electrical potential difference (voltage) (17.2, 18.2) 1496T_fm_i-xxvi 01/11/06 0:06 Page xxiv