Physical Mettalurgy of engineering materials Essay

Physical Mettalurgy of engineering materials - Essay Example 6. The three modes of heat transfer that occur during the heat treatment of steel are: Conduction Heat transfer is the heating process where heat energy is transferred from a body with a higher temperature to a body with lower temperature by direct contact of both bodies. Convection heat transfer is the heating process where heat is transferred by the motion of a heated medium, it could either be gas or liquid, to the body which is to be heated. Radiation heat transfer is the heating process by which heat is emitted from a higher temperature surface into space, then absorbed by a lower temperature surface thru the radiation of heat waves. 8. Stopped flow technique is limited to the one that does not have optical signal for the reaction of interest and the signals cannot be interpreted rigorously if the extinction coefficients of its intermediates are not known. Chemical quench flow allows the mixing of two reactants after which it is followed by quencing of chemical agents usually acid or base. Rapid optical photolisis chamber is based on the worldwide leading quench-flow and mounts to the same system. atomic size factor. The size factor is said to be favorable if the size of the atom does not differ by more than 14-15% from the solvent atom. The electrochemical effect, will have a difference in electronegativity between small solvent and solute atoms.The relative valency effect is when a metal of higher valency will dissolve a metal of a lower valency. Therefore, to complete solid solubility, both elements should have the same valency. In the crystal structure, the formation of the series of continuous solid solutions is posible if the components have the same crystal