In this article we will discuss about:- 1. Meaning of Diffusion 2. Importance of Diffusion 3. Applications 4. Types 5. Mechanisms 6. Activation Energy 7. Self-Diffusion 8. Diffusion in Oxides and Ionic Crystals 9. Grain Boundary and Surface Diffusion 10. Factors that Influence Diffusion. Contents: Meaning of Diffusion Importance of Diffusion Applications of Diffusion Types of Diffusion Diffusion Mechanisms Activation [...]
Fick proposed laws governing the diffusion of atoms and molecules, which can be applied to the diffusion processes in metals and alloys. He proposed two laws, the first for steady-state condition and unidirectional flow of atoms and the second law which deals with time dependence of concentration gradient; and the flow of atoms in all directions. Fick's First Law: Pick's [...]
In this article we will discuss about the Fick’s law of diffusion. Consider a chamber in which two different gas species, B and C, at the same temperature and pressure are initially separated by a partition. The left compartment has a high concentration of gas B (dark circles) whereas the right compartment is rich in gas C (white circles). Higher [...]
Consider evaporation of water contained in a tube or tank and its subsequent diffusion through the stagnant layer of air over it. Assumptions: (i) The system is under steady state and isothermal conditions (ii) The total pressure within the tube is constant and equal to the outside pressure (iii) Both air and water vapours behave as perfect gases (iv) Air [...]
In this article we will discuss about the general equation for mass transfer. Also learn about equimolal diffusion. General Equation of Mass Diffusion: Consider mass balance of species B diffusing through a control volume (dx × dy × dz) in a solid or stationary fluid medium C. Accumulation of mass of species B in the elemental volume due to its [...]
In this article we will discuss about the general equation for mass transfer. Also learn about equimolal diffusion. General Equation of Mass Diffusion: Consider mass balance of species B diffusing through a control volume (dx × dy × dz) in a solid or stationary fluid medium C. Accumulation of mass of species B in the elemental volume due to its [...]
In this article we will discuss about:- 1. Introduction to Diffusion of Metals 2. Atomic Models of Diffusion of Metals 3. Factors 4. Fick's Laws 5. Homogenisation. Contents: Introduction to Diffusion of Metals Atomic Models of Diffusion of Metals Factors Effecting Diffusion of Metals Fick's Laws of Diffusion of Metals Homogenisation and Diffusion of Metals 1. Introduction to Diffusion of [...]