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Updated: Apr 30, 2026

Determining the Mechanical Strength of Ultra-Fine-Grained Metals
Published on: November 22, 2021
Ideal shear strength of a quantum crystal
Edgar Josué Landinez Borda1, Wei Cai2, Maurice de Koning1
1Instituto de Física "Gleb Wataghin," Universidade Estadual de Campinas, UNICAMP, 13083-859 Campinas, São Paulo, Brazil.
Abstract:
Using path-integral Monte Carlo simulations, we compute the ideal shear strength (ISS) on the basal plane of hcp (4)He. The failure mode upon reaching the ISS limit is characterized by the homogeneous nucleation of a stacking fault and it is found to be anisotropic, consistent with Schmid's law of resolved shear stress. Comparing the ISS of hcp (4)He to a large set of classical crystals shows that it closely fits the approximately universal modified Frenkel model of ideal strength. In addition to giving quantitative stress levels for the homogeneous nucleation of extended defects in hcp (4)He, our findings lend support to assumptions in the literature that inherently classical models remain useful for the description of mechanical behavior in quantum crystals.
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