CSU – MSE 505 Kinetics Materials

Course Information

Principles of kinetics and phase transformations for engineering materials and their applications

Course Objective

The main objective of Kinetics of Materials is to introduce graduate-level principles and practical applications of kinetics and phase transformation for engineering materials involving phenomena including diffusion, movement of interfaces, solidification, and nucleation and growth.  The course also aims to provide graduate-level training in critical thinking, mathematical analysis, and written communication skills focusing on problems of interest involving kinetics and phase transformation of engineering materials

Course Syllabus with Suggested Schedule

EMA 5001 Physical Properties of Materials SYLLABUS

Lecture Slides & Videos

Lecture slides (PDF)Lecture videos (To be updated)Other Info
Lecture 00  Course infoInstructor, textbook, policy, website, and gradingLecture 00 homework answers & hints
Course objectives
 Thermodynamics quick refresher
 Kinetics & phase transformation vs thermodynamics
 Example – steel hardness vs cooling rate
 Example – B4C morphology vs synthesis condition
 Topics covered and schedule
 Application examples for kinetics & phase transformation
Lecture 01  Diffusion – introductionDiffusion definition and diffusing species
 Different ways to classify diffusion phenomena
 Descriptions-applications-characteristics of diffusion
 Down-hill diffusion
 Up-hill diffusion
 Binary phase diagrams with miscibility gap
 Additional considerations on down-hill vs up-hill diffusion
Lecture 02  Atomistic mechanism of diffusionDiffusion mechanism: Vacancy vs InterstitialLecture 02 homework answers & hints
 Atomistic model for interstitial diffusion & Fick’s 1st law
 Crystal structure and concentration effects on interstitial diffusion coefficient
 C interstitial diffusion in FCC-Fe
 Thermal activation of diffusion
Lecture 03  Steady-state & non-steady-state diffusion – Fick’s 2nd lawSteady state diffusion and concentration profileLecture 03 homework answers & hints
 Non-steady state diffusion and Fick’s 2nd Law
 Change of concentration profile with time
 Diffusion example – Homogenization
 Diffusion example – Spin-on dopant
 Diffusion example – Infinite diffusion couple
 Diffusion example – Carburization and Decarburization
 Diffusion length
 Random walk and Diffusion length
Lecture 04 Self-diffusion & vacancy diffusionSelf diffusion
 Self diffusion coefficient and examples
 Vacancy diffusion and relationship with self diffusion
Lecture 05  Substitutional diffusion in alloysKirkendall effect
 Atoms asymmetric movement wrt a lattice plane
 Darken’s equations and Interdiffusion coefficient
 Considerations on interdiffusion coefficient
 Mobility and Diffusion coefficient relationship
 Thermodynamic factor & relationships between self-intrinsic-inter diffusion coefficients
Lecture 06  Determine diffusion coefficient & Matano analysisDetermine D when independent of concentration
 Boundary conditions for general isothermal interdiffusion
 Boltzmann transformation
 Matano analysis for D changing with concentration
 Matano interface and its significance
Lecture 07  Short-circuit diffusion & reaction diffusionGrain boundary diffusion
 Temperature effect on grain bulk vs grain boundary diffusion
 Diffusion along dislocations
 Reaction diffusion
 Reaction diffusion – Interface velocity
 Down-hill diffusion in a single-phase region
 Down-hill diffusion involving a two-phase region
Lecture 08  Diffusion – other problemsExpectations about diffusionLecture 08 homework answers & hints
 D for interstitial carbon atoms in iron: BCC-Fe vs FCC-Fe
 Successful jump frequency
 Kirkendall interface moving velocity
 Example for use of Darken’s equations
Lecture 09  Surface energyClassification of interfaces
 Liquid-gas interfacial energy & Surface tension
 Surface energy for FCC (111) plane
 Surface energy for FCC (002) plane
 Surface energy for FCC (220) plane
 Surface energy for a plane rotating away from a low index plane
 Wuff construction and crystal equilibrium shape
Lecture 10  Grain boundariesTilt grain boundary & Twist grain boundary
 Small angle grain boundaries
 Tilt GB energy vs misorientation angle
 Twin boundaries
 Measure GB energy vs misorientation angle
 Driving force for general GB migration
 Driving force for GB straightening
 Driving force for GB rotation
 Boundary between three neighboring grains
 Stability of grain shape
 Grain growth kinetics
 Grain boundary segregation
Lecture 11  Interfaces and precipitate shapeCoherent interfaceLecture 11 homework answers & hints
 Semi-coherent interfaceBkTiC-ZrC semi-coherent interface from
Li et al. Ceram Int 41(10) 14258 (2015)
 Incoherent interface
 Shapes of fully coherent and incoherent precipitates
 Shapes of partially coherent precipitates
 Shapes of precipitates at GB
 Volume strain on precipitate shape and Coherence loss in growth
 Solid-liquid interfaces
Lecture 12  Solidification via homogeneous nucleationSolidification and Nucleation-growth process
 Classification of nucleation-growth type phase transformations
 Solidification examples
 Barriers in reaction or phase transformation
 Solidification via homogeneous vs heterogeneous nucleation
 Free energy change in solidification via homogeneous nucleation
 Driving force vs undercooling in solidification
 Critical nucleus size vs undercooling in solidification
 Nucleation barrier vs undercooling in solidification
 Critical nucleus size vs Max cluster size – Nucleation temperature
 Homogeneous nucleation rate
Lecture 13 Solidification via heterogeneous nucleationFree energy change and critical nucleus size for solidification via heterogeneous nucleation
 S factor for solidification via heterogeneous nucleation
 Heterogeneous nucleation rate for solidification
 Other factors influencing heterogeneous nucleation rate
 Two growth modes of solid from liquid for a pure element
 Continuous growth for a pure element solid
 Lateral growth for a pure element solid
 Planar growth of a pure element solid into superheated liquid
 Dendritic growth of a pure element solid into supercooled liquid
Lecture 14 Alloy solidificationAlloy EQUILIBRIUM solidification
 Alloy solidification with stirring
 Alloy solidification with stirring – Coring
 Alloy solidification with stirring – Concentration profile change
 Alloy solidification with stirring – Analytical solution
 Alloy solidification – NO stirring in liquid
 Constitutional supercooling in alloy solidification
Lecture 15 Solidification other issuesEutectic solidification
 Zones formed during solidification and controlling cast structure
 Expectations for solidification and homogeneous/heterogeneous nucleation
Lecture 16 Diffusional phase transformationIntroduction to solid state phase transformation
 Characteristics of solid state phase transformation
 1st & 2nd order phase transformation
 Phase diagrams and common solid state phase transformations
Lecture 17 Nucleation in precipitationIntroduction to precipitation in solid
 Homogeneous nucleation in solid
 Driving force for homogeneous nucleation in solid precipitation
 Nucleation rate for homogeneous precipitation
 Nose-shaped curve of nucleation rate for homogeneous precipitation
 Heterogeneous precipitation
Lecture 18  Growth of precipitatesPrecipitate growth and shape
 Diffusion controlled planar growth of incoherent precipitate
 Nose-shaped rate curve for precipitates growth
 Growth of other precipitates
Lecture 19  Spinodal decompositionIntroduction to Spinodal decomposition
 Solid miscibility gap – example of Cu-Ni
 Spinodal decomposition – free energy-composition curve
 Spinodal decomposition – Composition change over time
 Nucleation-growth within miscibility gap
 Spinodal decomposition vs nucleation-growth
 Driving force for spinodal decomposition
 Interfacial chemical energy and coherent strain energy
 Coherency strain and coherent spinodal
 Wavelength for composition modulation from spinodal decomposition
Lecture 20  Massive transformation and particle coarseningIntroduction to other phase transformations
 Precipitate coarsening
 Massive transformation
 Order-disorder transformation
Lecture 21  Martensite transformationFe-Fe3C phase diagram and Martensite transformation
 Martensite transformation – At low T to meta-stable phase
 Martensite transformation – Surface roughness and microstructures
 Martensite transformation – Diffusionless and Athermal
 Lattice misfit of C in Fe and BCT structure
 Crystallography considerations for Martensite transformation in carbon steel
  
Lecture 23 Models for transformation kineticsTTT and CT curves
 Nucleation and growth kinetics for very low conversion
 Nucleation and growth kinetics for high conversion – JMA equation
 Nucleation and growth kinetics with site saturation
 Nucleation and growth kinetics with diffusion control
 Interpretations of JMA equation exponent factor n
 Diffusion controlled 1D growth kinetics
 Diffusion controlled shrinking core model
 Interface controlled shrinking core model
 Summary of kinetic models