a thermodynamic model for carbon trapping in lattice defects

(PDF) Perspectives on point defect thermodynamics Jutta

Since there is only one degree of freedom,represented by y C ,it is very simple to obtain the result for the carbon concentration:G C = 1 3 (G Fe:C G Fe:Va ) ,(80) G Fe:C G Fe:Va + 3RT ln y * C 1 y * C + (1 2y * C )L Fe:C,Va C = 0.(81)Thus,if we assume the carbon concentration is very small and neglect terms in y C compared to unity,we can express the equilibrium carbon concentration asy * CA thermodynamic model for carbon trapping in lattice defectsDec 01,2008·Abstract.A thermodynamic model in the framework of the CALPHAD method is proposed to describe the distribution of interstitial solute (carbon) atoms in bcc-iron during tempering of martensite.In the model,the crystal defects are introduced as a separate sublattice,which is a highly favored lattice position for carbon compared to undisturbed interstitial sites or precipitate sites in cementite.Ab Initio Thermodynamics and the Relationship between @article{Chaka2016AbIT,title={Ab Initio Thermodynamics and the Relationship between Octahedral Distortion,Lattice Structure,and Proton Substitution Defects in Malachite/Rosasite Group Endmember Pokrovskite Mg2CO3(OH)2.},author={A.Chaka},journal={The journal of physical chemistry.

Calphad Vol 32,Issue 4,Pages 611-708 (December 2008

Read the latest articles of Calphad at ScienceDirect,Elseviers leading platform of peer-reviewed scholarly literatureCited by 11Publish Year 2013Author J Svoboda,Y V Shan,E Kozeschnik,F D FischerDetermination of depths of traps for interstitials from Jul 30,2013·We introduce the volume V L,[V L] = m 3 mol 1,which corresponds to one mole of interstitial positions in the lattice and which can be occupied by freely diffusing carbon (lattice positions).Analogously,the volume V T ,[ V T ] = m 3 mol 1 ,is introduced,which corresponds to one mole of interstitial positions,which can be occupied by trapped carbon (trap positions).Cited by 11Publish Year 2013Author J Svoboda,Y V Shan,E Kozeschnik,F D FischerMatcalc - Solid State and Kinetics PrecipitationM.Maalekian and E.Kozeschnik, A thermodynamic model for carbon trapping in lattice defects ,Calphad 32 (2008) 650-654.E.Kozeschnik, Thermodynamic prediction of the equilibrium chemical composition of critical nuclei bcc Cu precipitation in alpha-Fe ,Scripta Mater.,59 (2008) 1018-1021.

Cited by 22Publish Year 2008Author M.Maalekian,E.Kozeschnik,E.KozeschnikA thermodynamic model for carbon trapping in lattice

Request PDF A thermodynamic model for carbon trapping in lattice defects A thermodynamic model in the framework of the CALPHAD method is proposed to describe the distribution of interstitial Cited by 22Publish Year 2008Author M.Maalekian,E.Kozeschnik,E.KozeschnikA thermodynamic model for carbon trapping in lattice defectsA thermodynamic model in the framework of the CALPHAD method is proposed to describe the distribution of interstitial solute (carbon) atoms in bcc-iron during tempering of martensite.In the model,the crystal defects are introduced as a separate sublattice,which is a highly favored lattice position for carbon compared to undisturbed interstitial sites or precipitate sites in cementite.DEFECTS AND DISORDER IN CARBON NANOTUBESFurthermore,the carbon-rich synthetic environment excludes the likelihood of vacancy survival,beyond mere thermodynamic considerations.Vacancy defects are not uncommon,however,and are produced post-synthesis.For example,knock-on events by high energy electron,ion,or neutron radiation can dislodge or fully remove a carbon atom.

Density functional study of carbon vacancies in titanium

concentrations.Lattice relaxations around a carbon vacancy were also addressed,using a 64-atom supercell.The titanium atoms closest to the carbon vacancy were found to relax outward,away from the carbon vacancy.Also,within this model,the lattice relaxations were found to be very local-ized.Later,the atomic relaxations around vacancies Determination of depths of multiple traps for Aug 12,2014·The model of diffusion [1,2] assumes point traps and neglects the fact that an interstitial atom may jump out of the trap to another lattice position and then jump back into the trap.Moreover,the model neglects the possibility that an interstitial atom can diffuse along interconnected traps.The authors are aware of these facts.Determination of depths of traps for interstitials from Carbon acts as an interstitial component in most crystals.Its amount in the solid can be described by its molar concentration c,[c] = molm3,being the sum of the molar concentration of freely diffusing carbon in the defect-free lattice denoted as c L and the molar concentration of the carbon situated in the practically immobile traps denoted as c T,c = c

Determination of depths of traps for interstitials from

Jul 30,2013·In this paper,a rigorous thermodynamically based concept is offered to extract the value of trapping enthalpy E from chemical potentials of interstitial atoms which are,for instance,available in the form of CALPHAD-type thermodynamic databases.Exemplarily,the values of E for C-trapping at Cr impurities are evaluated.For comparison,trapping enthalpies of C at various typical alloyingDynamic Performance Simulation of AlGaN/GaN HighUnder thermodynamic equilibrium,for a given number of sites and configuration (which is 1 for native point defects being investigated here),defect formation energy can be used to determine concentration.Thermodynamic equilibrium represents growth conditions,which more accurately correlates to MOCVD grown samples due to the higher temperatures.Modeling Deep Burn TRISO particle nuclear fuel -·Ramasubramaniam et al.have developed an off-lattice,on-the-fly kMC model for simulating stress-assisted diffusion and trapping of hydrogen by crystalline defects in BCC iron.The model employs precomputed transition rates obtained with high-accuracy DFT calculations in defect-free parts of the crystal.

Some results are removed in response to a notice of local law requirement.For more information,please see here.12345NextTalid Sinno University of Pennsylvania - Academia.edu

The implantation process leads to extensive lattice damage,which must be healed by thermal annealing. All thermophysical parameters for describing point defect transport and thermodynamics used in the model were obtained independently using regression to other experimental systems.The results of this work demonstrate the potential utility Thermodynamic modeling of carbon clusters in martensite In the model,the crystal defects are introduced as a separate sublattice,which is a highly favored lattice position for carbon compared to undisturbed interstitial sites or precipitate sites in

Thermodynamics of order and randomness in dopant

@article{osti_1772660,title = {Thermodynamics of order and randomness in dopant distributions inferred from atomically resolved imaging},author = {Vlcek,Lukas and Yang,Shize and Gong,Yongji and Ajayan,Pulickel and Zhou,Wu and Chisholm,Matthew F.and Ziatdinov,Maxim and Vasudevan,Rama K.and Kalinin,Sergei V.},abstractNote = {Abstract Exploration of structure-property relationships

Related Post

Leave a message