EGN3365
Activation Energy
minimum energy required for a chemical reaction to occur.
Carburizing
Diffuse carbon atoms into host iron atom at the surface. increases the hardness and wear resistance of the iron.
Diffusion
movement of atoms within a material
Diffusion coefficient
D [m²/2]
Diffusion flux
J=M/At
Ficks First Law
high concentration to low concentration
Ficks second Law
prediction of change in concentration gradient with time due to diffusion
Interstitial diffusion
smaller attoms diffuse between atoms (more rapid then vacancy diffusion)
Non steady-state diffusion
a time dependent process in which the rate of diffusion is a function of time
Self-diffusion
In an element solid atoms also migrate.
Steady-state diffusion
the net movement of a species down a concentration gradient, from an area of high concentration to an area of low concentration
Vacancy diffusion
atoms exchange with vacancies.