Anisotropy deformation behavior of multi-layer black phosphorus

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Black phosphorus (b-P) is a 2D van der Waals semiconductor with notable physical and chemical properties.
• Its machinability is recognized, but the deformation mechanisms and their link to mechanical properties require further investigation.

Purpose of the Study:

• To investigate the anisotropic deformation behavior of multi-layer black phosphorus.
• To elucidate the correlation between deformation mechanisms and mechanical properties under tensile and nanoindentation loading.

Main Methods:

• Molecular Dynamics (MD) simulations were employed to model tensile and nanoindentation processes.
• Density Functional Theory (DFT) calculations were used to determine interlayer interaction energies during slip and cleavage.

Main Results:

• Tensile loading shows irregular crack propagation along the zigzag orientation and straight propagation along the AC orientation.
• Nanoindentation reveals brittle fracture with specific crack orientations under in-plane loading.
• Out-of-plane loading induces significant interlayer slip plastic deformation due to lower interlayer sliding energy and higher cleavage energy.

Conclusions:

• The study provides insights into the anisotropic mechanical response of multi-layer black phosphorus.
• Findings offer a theoretical basis for understanding b-P deformation and serve as a reference for mechanical machining processes in device applications.