Prof A L Greer
This course covers time-scales from sub-ns in computer memory to giga-years in meteorites. Thermodynamics determines what cannot happen; kinetics determines what does happen. Today, study of kinetics is revolutionised by:
(i) nanotechnology, where the usual balance between volume and surface effects is disrupted;
(ii) characterisation methods of unprecedented capability, from synchrotron X-ray imaging to ultra-fast laser and calorimetry techniques.
We build on earlier courses and focus on principles, rather than details, of atomistic mechanisms to understand transformations, relevant in:
(i) production and optimisation of materials
-- from DC casting of multi-tonne aluminium ingots to production of nanotubes;
(ii) stability and reliability of materials and devices
-- from superalloy creep resistance to integrated circuit reliability as Moore’s Law explores new limits;
(iii) device operation
-- glass formation and fast crystallisation exploited in phase-change memory, with potential to transform memory and deliver ‘neuromorphic’ computing.
This lecture course will cover:
- Atomic and molecular diffusion in crystals: interdiffusion, doping, Kirkendall effects
- Transport in liquids: diffusivity and viscosity, fragility
- Glasses: glass transition, fictive temperature, relaxation and rejuvenation
- Surface transport: sintering, ultrastable glasses, whisker growth
- Electromigration: electron-wind effects reliability of integrated circuits
- Interface migration: grain growth
- Solidification: contributions to supercooling, nucleation and grain refinement
- Fast growth: solute trapping, disorder trapping, phase-change memory
- Devitrification: high driving force and many pathways
- Diffusional control of rates: precipitation. Ostwald ripening, eutectic growth.
- Ordering transformations: first- and second-order
- Overall reaction kinetics: the classical Avrami analysis – its strengths and limitations