Atomistic simulation of slow grain boundary motion

Area of Science:

• Materials Science
• Computational Materials Science
• Physics

Background:

• Atomistic simulations of grain boundary motion are crucial for understanding material properties.
• Current methods face limitations in simulating realistic experimental conditions, particularly at lower temperatures and velocities.

Purpose of the Study:

• To develop an adapted simulation method for studying grain boundary motion under experimentally relevant conditions.
• To enable the extraction of grain boundary mobilities in the zero driving force limit at low temperatures (∼0.2T(m)).

Main Methods:

• Introduction of an adapted atomistic simulation technique.
• Simulation of grain boundary motion at velocities within the experimental range.
• Analysis of boundary mobilities at zero net driving force and temperatures as low as 0.2 times the melting point (T(m)).

Main Results:

• The adapted method successfully accesses grain boundary velocities comparable to experimental ranges.
• Mobility extraction in the zero driving force limit is achieved at low temperatures (∼0.2T(m)).
• Three distinct mechanistic regimes of grain boundary mobility were identified at zero net velocity, dependent on system temperature.

Conclusions:

• The developed simulation method overcomes limitations of existing techniques for studying grain boundary motion.
• This advancement allows for more accurate comparisons between atomistic simulations and experimental observations.
• The identification of temperature-dependent mobility regimes provides new insights into grain boundary dynamics.