(a) Cite the major differences between activation and concentra (a) Cite the major differences between activation and concentration polarizations. (b) Under what conditions is activation polarization rate controlling? (c) Under what conditions is concentration polarization rate controlling?
(a) Briefly describe the microstructural difference between sphe (a) Briefly describe the microstructural difference between spheroidite and tempered martensite. (b) Explain why tempered martensite is much harder and stronger.
(a) Briefly cite the main differences between ionic, covalent, (a) Briefly cite the main differences between ionic, covalent, and metallic bonding. (b) State the Pauli Exclusion Principle.
Aluminum–lithium alloys have been developed by the aircraft indu Aluminumâlithium alloys have been developed by the aircraft industry to reduce the weight and improve the performance of its aircraft. A commercial aircraft skin material having a density of 2.55 g/cm3 is desired. Compute the concentration of Li (in wt %) that is required
(a) A three-point transverse bending test is conducted on a (a) A three-point transverse bending test is conducted on a cylindrical specimen of aluminum oxide having a reported flexural strength of 390MPa (56,600psi). If the specimen radius is 2.5 mm (0.10 in.) and the support point separation distance is 30 mm (1.2 in.), predict whether […]
Allowed values for the quantum numbers of electrons are as follows: Allowed values for the quantum numbers of electrons are as follows: n = 1, 2, 3, . . . l = 0, 1, 2, 3, . . . , n − 1 ml = 0, ±1, ±2, ±3, . . . ,±l ms = ±12 The […]
An alloy steel (4340) is to be used in an An alloy steel (4340) is to be used in an application requiring a minimum tensile strength of 1380MPa (200,000psi) and a minimum ductility of 43%RA. Oil quenching followed by tempering is to be used. Briefly describe the tempering heat treatment.
Briefly explain why, for a small anode-to-cathode area ratio Briefly explain why, for a small anode-to-cathode area ratio, the corrosion rate will be higher than for a large ratio.
Briefly explain why the hardness of tempered martensite diminish Briefly explain why the hardness of tempered martensite diminishes with tempering time (at constant temperature) and with increasing temperature (at constant tempering time).
(a) Briefly explain why Cv rises with increasing temperature at (a) Briefly explain why Cv rises with increasing temperature at temperatures near 0 K. (b) Briefly explain why Cv becomes virtually independent of temperature at temperatures far removed from 0 K.