Molecular dynamics simulations are utilized in this study to investigate the underlying mechanisms governing nanomechanical behavior in single-crystal Al-Mg-Si alloys subjected to cryogenic conditions. Cryogenic environments significantly enhance dislocation density and Young's modulus through the formation of stable dislocation networks, thereby strengthening the mechanical response during indentation processes. Regarding friction behavior, cryogenic conditions suppress surface atomic mobility, resulting in dislocation densities that increase by 137% compared to room temperature with deep-layer distribution patterns. This configuration leads to the formation of stable work-hardened layers, achieving characteristics of "small deformation and low wear" while substantially decreasing wear rates.