Energy of Void in FCC Copper Crystal Under Uniaxial Tensile DeformationLAMMPS Tammy TancharoensuksavaiMTSE 4040 Final Project

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Energy of Void in FCC Copper Crystal Under Uniaxial Tensile Deformation

FCC Cu Crystal - no void

20 x 20 x 20 nm box

Void Sizes & their Nucleation Sites

r=2nmr=3nmr=4nm

Slip SystemsSchmids Law = *m is equal to the stress applied to the material () multiplied by the cosine of the angle with the glide plane () and the cosine of the angle with the glide direction ()Schmid Factor m = cos()*cos()

Slip Systems

DislocationsDislocation motion in FCC crystals is governed by the critical resolved shear stress via Schmids lawStacking fault energy has been used to predict energy at a crack tipHomogeneous nucleation depends on both Schmid & non-Schmid normal factortogether they represent resolved shear stress in the direction of slip and resolved tensile stress normal to the slip plane

No Void

Red BCCPurple HCPGrey unknown

No Void

No Void

2nm radius void

Red BCCPurple HCPGrey unknown

2nm radius void

3nm radius void

Red BCCPurple HCPGrey unknown

3nm radius void

4nm radius void

Red BCCPurple HCPGrey unknown

4nm radius void

Conclusion:Energy of FCC Cu CrystalVolume remains fixed within system at 377933.0670Energy minimizes for every stepEnergy decreases as radius decreases

ReferencesDas, Ashis, and Gaurav Singh. "Plastic Deformation and Failure Studies near a Void for Copper-aluminium Alloy via Molecular Dynamics Simulation." Thesis. Department of Metallurgical and Materials Engineering National Institute of Technology, Rourkela, 2014. Print.Tschopp, M., Spearot, D., & Mcdowell, D. (2007). Atomistic simulations of homogeneous dislocation nucleation in single crystal copper. Modelling and Simulation in Materials Science and Engineering, 693-709.Wang, T., Wang, Y., Hsieh, T., Chang, S., & Cheng, Y. (n.d.). Copper voids improvement for the copper dual damascene interconnection process. Journal of Physics and Chemistry of Solids, 566-571.