Intrinsic Stacking Fault energy || LAMMPS script || FCC || Planar Defects

Intrinsic Stacking Fault energy for FCC materials can be calculated with the help of this LAMMPS script example.
Three defects in materials -
1. Point defects (vacancies)
2. Line defects (dislocations)
3. Planar defects (Stacking Faults)
In this video, we focus on stacking faults - planar defects - particularly intrinsic stacking faults,
stacking faults are irregularities in the stacking sequence; the naturally stacking sequence in ABCABCABCABC...............
But when the intrinsic stacking fault is created, the stacking arrangement changes to ABCBCABC….
This disrupture of stacking sequence of the perfect crystal - increases the energy of the crystal - so we calculate the increase in energy per unit area of the stacking fault.
SFE = [ E(stacking fault) - E(perfect crystal) ]/ Area
SFE. - Stacking Fault Energy
Githib website for the code:
github.com/NextZenStudent/Int...
Website: nextzenstudent.com

[@chimaugwuegbu9618]

Thanks a lot for this great video on the calculation of SFE. In some input scripts, you will see the following commands: "variable a loop 20" and "label forloopt". Kindly explain why these commands are added to GSFE input scripts. Thanking you in anticipation.

[@gaussianbilgi]

Thank you for video. Can you calculate the adsorption of an organic compound on the metal surface?

[@NextZenStudent]

if there is a journal or scientific article on adsorption of organic compound on a metal surface. please forward the doi to my email: [e-mail]. I will see if it can be done quickly

[@rajarajank1362]

1.May I know how I can see twin boundaries along with the dislocations? 2. How see the Burgers vectors in OVITO?

[@NextZenStudent]

you can't see twin boundaries in Ovito you have to click on dislocations after doing DXA, then select Show Burgers vector I have discussed it in the following video: kzbin.info/www/bejne/sHbChIR7et5pf8U

[@jhonatanandrade7400]

Hi. Do you have videos about nanoindentation? I am developing a work on nanoindentation in the crystalline planes [001], [011] and [111] in a high entropy alloy, I also use Ovito. Can you help me?

[@NextZenStudent]

I have to make video on nano indentation. Give me a week, I will get back to you on the nanoindentation and a video. Thank you for asking

[@jhonatanandrade7400]

Nice, but can I send you an email with a script I made and ask a question about the region command (rotate and move)?

[@NextZenStudent]

Sure , you can. [e-mail]

[@neerajkumarbhoi660]

Sir, Can you help me with solving this problem? Sir, I am modelling the Aluminum (Al) and Silicon carbide (SiC) material with LAMMPS. In my case, the Aluminum is matrix phase with higher content and silicon carbide is a reinforcement element with a few percentages such as 10wt.% and 15 wt.%. Both the particles are in a spherical form and the material is combined to form a composite phase of the Al-SiC material.

[@NextZenStudent]

Yes, I am making a video on it. I will talk about on next 3 videos

[@neerajkumarbhoi218]

@@NextZenStudent thank you so much sir.

[@soumyadebdey5747]

Could you please tell me how to calculate SFE at different temperatures?

[@NextZenStudent]

sure. will try to make a video on it

[@prasadtinku6956]

i was trying to find gsfe for HCP material (Mg) but not getting exact result. can you help me to edit this code for hcp material?

[@manvendramishra8142]

Bro I'm working on HCP Mg, can you provide contact number?

[@manvendramishra8142]

Bro can you provide your contact details?

[@manvendramishra8142]

bro??

[@mustafaaeea2722]

Hi can we use the same code for stacking fault in bcc Molybdenum? I tried to change fcc by bcc but it doesn't work,Can you guide plz

[@NextZenStudent]

can you send me the research article you are following to obtain Stacking fault energy for BCC structure. email: [e-mail].

[@waqasakhtar4842]

hi brother, i also have the same question. i want to create stacking faults in BCC Molybdenum using MD, I am following your code and also the help guide code from the LAMMPS website but the problem is it doesn't execute after running few steps it give me error. if you say I will send you my Molybdenum Potential file you also can try to help me out. thanks

[@waqasakhtar4842]

icme.hpc.msstate.edu/mediawiki/index.php/LAMMPS_Intrinsic_Stacking-Fault_Energy.html I am using code from this link but it shows me an error. After reading the potential file my simulation stop and just give me empty log file, and an error file.

[@NextZenStudent]

yes I saw it. Can you send me the lammps code and potential file to my email: [e-mail]. I am asking for a the article since it is BCC and not FCC. FCC has HCP stacking fault atoms, I am not sure which stacking fault atoms (whether it is HCP or FCC) are for BCC structure. Then only you can decide the BCC crystal orientation for lammps simulation and displace atoms in correct direction to get the appropriate stacking fault atoms

[@waqasakhtar4842]

@@NextZenStudent I have sent my written code and potential file to the given email address.

[@manvendramishra8142]

Anyone working with Mg in Lammps ??

[@Computational_materials]

How to get GSFE curve?

[@NextZenStudent]

GSFE (Generalized Stacking Fault Energy) curve requires displacing atoms continuously and measuring the SFE. In my next set of videos I will talk on this

[@Computational_materials]

I want to calculate the effect of solid solution strengthening in an alloy, is it possible by md to calculate excess stress because of solid solution hardening? If yes, than please mail me at [e-mail], it will be a great help. Thanks.

[@NextZenStudent]

Hi @Sandeep, can you find a paper on MD simulation - solid solution strengthening of alloys. It helps you and me as well to discuss clearly. please send an email of the paper link/pdf to [e-mail]

[@jessbrown602]

Can you explain the meaning of "w.r.t" which appeared in your video?

[@NextZenStudent]

it means ' with respective to'

[@jessbrown602]

@@NextZenStudent Thank you very much!

[@jessbrown602]

​@@NextZenStudent I want to know how to plot the GSFE curve,that will help a lot! thank you.

[@daramolaayobami6197]

can you include temperature in this

[@NextZenStudent]

yes I can do that. I will talk in next set of videos

[@daramolaayobami6197]

@@NextZenStudent please paste the script here

[@NextZenStudent]

# --------------------- INITIALIZAITION --------------------- clear units metal dimension 3 boundary p p s atom_style atomic variable latparam1 equal 3.52 variable x_displace equal -1*(${latparam1}/sqrt(6)) variable xdim equal ${latparam1}*sqrt(6)/2*10 variable ydim equal ${latparam1}*sqrt(2)/2*10 variable zdim equal ${latparam1}*sqrt(3)*6 # --------------------- CRYSTAL STRUCTURE DEFINITION --------------------- lattice fcc ${latparam1} region 1 block 0 ${xdim} 0 ${ydim} 0 16.5 units box region 2 block 0 ${xdim} 0 ${ydim} 16.5 36.5808 units box region whole block 0 ${xdim} 0 ${ydim} 0 36.5808 units box create_box 2 whole lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 1 region 1 lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 2 region 2 # --------------------- EAM POTENTIAL --------------------- pair_style eam/alloy pair_coeff * * FeCuNi.eam.alloy Ni Ni # --------------------- SETTINGS --------------------- compute peratom all pe/atom compute eatoms all reduce sum c_peratom thermo 1 thermo_style custom step pe c_eatoms dump 1 all custom 1 dump.relax.1.* id type xs ys zs c_peratom run 0 variable E equal "c_eatoms" variable Eo equal $E #variable E equal "c_eatoms" computes the initial energy of the model before any sliding is done #E is necessary to store the initial energy in Eo group bot region 1 group top region 2 displace_atoms top move ${x_displace} 0.0 0.0 units box #displace_atoms is the command neccessary to move atoms into the next stacking arrangement (ie: A -> B) fix 1 all setforce 0 0 NULL min_style cg minimize 1e-10 1e-10 1000 1000 variable Ef equal "c_eatoms" variable Cf equal 1.60217657e-16 variable A equal (${xdim}*${ydim})*1e-20 variable SFE equal ((${Ef}-${Eo})*${Cf})/${A} #variable Ef equal "c_eatoms" computes the final energy of the system after sliding is done #variable A is the area of the Stacking fault plane #variable Cf is the conversion factor of electro volts to millijoules #variable SFE is the stacking-fault energy of the system #################################### # SIMULATION DONE print "All done" print "Initial energy of atoms = ${Eo} eV" print "Final energy of atoms = ${Ef} eV" print "Stacking-fault energy = ${SFE} mJ/m^2"

[@daramolaayobami6197]

@@NextZenStudent hi if i have pair_style eam/alloy pair_coeff * * FeCuNi.eam.alloy Fe Cu Ni which is three atoms, how do i correct the initialization setting create_box 2 whole lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 1 region 1 lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 2 region 2

[@NextZenStudent]

create_box 3 whole lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 1 region 1 lattice fcc ${latparam1} orient x 1 1 2 orient y -1 1 0 orient z -1 -1 1 create_atoms 2 region 2 set type 1 type/fraction 3 0.25 3456 set type 2 type/fraction 3 0.25 2567