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Related Experiment Video

Updated: May 30, 2026

Using Laser Scanning Microscopy to Determine Electromigration in Molybdenum Disilicide

Using Laser Scanning Microscopy to Determine Electromigration in Molybdenum Disilicide

Published on: May 23, 2025

Helium cluster dissolution in molybdenum.

O Runevall¹, N Sandberg

¹Department of Physics, Royal Institute of Technology, S-106 91 Stockholm, Sweden.

Journal of Physics. Condensed Matter : an Institute of Physics Journal

|August 11, 2011

Summary

This summary is machine-generated.

This study used atomistic simulations to investigate helium behavior in molybdenum. Results show helium migration is defect-assisted above 1100 K, aligning with experimental data.

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Last Updated: May 30, 2026

Using Laser Scanning Microscopy to Determine Electromigration in Molybdenum Disilicide

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Spatial Separation of Molecular Conformers and Clusters

Spatial Separation of Molecular Conformers and Clusters

Published on: January 9, 2014

Area of Science:

Materials Science
Nuclear Engineering
Computational Physics

Background:

Understanding helium behavior in materials is crucial for nuclear applications.
Molybdenum is a candidate material for fusion reactor components.
Helium embrittlement is a significant concern in materials exposed to irradiation.

Purpose of the Study:

To investigate helium retention and diffusion in molybdenum at an atomistic scale.
To quantify the thermal stability of helium-vacancy clusters.
To compare atomistic simulation results with experimental desorption spectra.

Main Methods:

Ab initio calculations using density functional theory (DFT).
Modeling of helium-vacancy clusters and their thermal stability.
Calculation of helium emission rates to predict desorption spectra.

Main Results:

Thermal stability of helium-vacancy clusters was quantified.
Calculated helium emission rates were used to derive a desorption spectrum.
Simulated desorption spectrum showed satisfactory agreement with experimental data, except at high temperatures.
Helium migration above 1100 K is primarily assisted by lattice defects (vacancies).

Conclusions:

Atomistic simulations provide valuable insights into helium behavior in molybdenum.
Defect-assisted diffusion is the dominant mechanism for helium migration in molybdenum at elevated temperatures.
Further refinement of models may be needed to fully capture high-temperature experimental observations.