Driving Forces for Change
Factors controlling Phase Transformations
Driving force
Equilibrium
Energy of Systems
Free energy
Entropy
Entropy (cont.)
First Law of Thermodynamics
Thermodynamics (continued)
Driving force for solidification
Solidification (cont.)
Solid State Phase Changes
Other Process Driving Forces
Diffusion
Diffusion Mechanisms
Steady State Diffusion
Steady State Diffusion (cont.)
Fick’s 1st Law of Diffusion
Non Steady-state Diffusion
Carburising
Carburising (cont.)
Carburising Example
Example (continued)
Factors Affecting Diffusion
Diffusion Distance
Nucleation
Nucleation (cont.)
Rate of Nucleation and Growth
TTT Curves
Email: s.j.bull@ncl.ac.uk
Home Page: http://www.staff.ncl.ac.uk/s.j.bull