The nanomechanical and tribological properties of twisted bilayers of graphene (TBGs) and other two-dimensional (2D) structurally lubric interfaces still warrant investigation, particularly about the possibilities of spontaneous, defect-free pinning. We show here through extensive sliding simulations that TBGs remain superlubric even under loads up to 10 GPa and twist angles down to $0.3^{\circ }$, with no evidence of pinning. To understand that, we studied a 2D Frenkel-Kontorova (FK) model—a twisted monolayer lattice in a periodic potential of variable magnitude $U_0$ and stiffness $K$. Aubry-type spontaneous pinning appears at small twists, albeit with extra large $U_0/K{a}^2$, when the width $w$ of moiré dislocations shrinks to $\sim 4a$, where $a$ is the lattice spacing. A complementary FK-type model based on realistic graphene elasticity and geometry confirms that most TBGs and twisted 2D interfaces lie far below the critical pinning threshold. Their strong in-plane bonds and weak interlayer interactions yield $U_0/K{a}^2$ orders of magnitude too small, and moiré dislocations remain wide, $w\gg a$. This provides a unified theoretical framework to understand and predict Aubry pinning transitions, establishing the dislocation width as a practical criterion for spontaneous Aubry pinning, and highlighting its general absence with resilience of sliding lubricity in twisted 2D material bilayers under ordinary conditions.

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• Friction
• Structural phase transition
• Graphene
• Twisted bilayer graphene
• Molecular dynamics