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ISSN E 2409-2770
ISSN P 2521-2419

Atomistic Insights into the Irradiation Effects in Molybdenum

Waqas Akhtar, M. Mustafa Azeem, Muhammad Bilal Khan

Vol. 9, Issue 12, PP. 187-192, December 2022


Keywords: Molecular dynamics, Molybdenum, Primary defect formation, Defect clusters, atomic scale

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 In this study, we examined the impact of energies of 2.54 keV and 5 keV displacement cascades in molybdenum (Mo) using an atomistic simulation at 300 K. The simulation was carried out using machines learning developed spectral neighbor analysis potential (SNAP). We computed displacement threshold energy ( ), vacancy formation energy ( , interstitial formation energy ( ), interstitial cluster formation energy ( ), activation energy barrier of interstitial , activation energy barrier of vacancy ( ), elastic properties, i.e., shear, bulk, young modulus, poison ratio. The simulations for primary displacement cascades were performed over a statistical average of 20 independent molecular dynamics simulations such that peak time and the surviving number of defects are inversely proportional to the incident energy of primary knock-on atoms (EPKA). Additionally, it is established that the number of clusters (Nclusters) during displacement cascades is directly proportional to EPKA. Furthermore, it was revealed that the number of interstitial clusters is higher than the number of vacancy clusters. This research will provide atomic insight into the interactions of defects in Mo for the development of structural materials for high temperature applications.

  1. Waqas Akhtar,, College of Material Science & Engineering, Harbin Institute of Technology, Harbin, 150001, China.
  2. Mustafa Azeem,, Department of Civil, Architectural, and Environmental Engineering, Missouri University of Science and Technology, Rolla, MO, 65409, USA.
  3. Muhammad Bilal Khan,, Department of Mechanical Engineering, Ghulam Ishaq Khan Institute of Engineering and Technology, Topi, Swabi 23640, KP, Pakistan.

Waqas Akhtar M. Mustafa Azeem Muhammad Bilal Khan Atomistic Insights into the Irradiation Effects in Molybdenum International Journal of Engineering Works Vol. 9 Issue 12 PP. 187-192 December 2022.

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