The lubrication performance of Cu nanofluid was studied through hot rolling tests and non-equilibrium molecular dynamics simulation. Results showed that nanofluid with 0.5 wt% Cu nanoparticles possessed the optimal effect in reducing the rolling force, finish rolling thickness and rolled surface roughness. The superior lubrication performance was attributed to the formation of protective tribofilm made of Fe/Cu debris, iron and copper oxides as well as amorphous substances with a thickness of about 24 nm, which avoided the direct contact of steel strip and the roll, thus inhibiting the adhesion wear. Molecular dynamics simulation disclosed that the rolling-dominated motion pattern of Cu nanoparticles with 74.1% rolling and 25.9% sliding motion contributed to a significant decrease in the friction force. Besides, surface defects including the peaks and valleys were polished and repaired by nanoparticles respectively, thus developing the surface quality of hot rolled products.

中文翻译：

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水基Cu纳米流体作为钢热轧润滑剂的实验研究和分子动力学模拟

通过热轧试验和非平衡分子动力学模拟研究了Cu纳米流体的润滑性能。结果表明，含0.5wt%Cu纳米颗粒的纳米流体在降低轧制力、精轧厚度和轧制表面粗糙度方面具有最佳效果。优越的润滑性能归因于形成了由Fe/Cu碎片、铁和铜的氧化物以及厚度约24nm的无定形物质构成的保护性摩擦膜，避免了钢带与轧辊的直接接触，从而抑制了粘着磨损。分子动力学模拟表明，74.1% 滚动和 25.9% 滑动运动的 Cu 纳米粒子以滚动为主的运动模式有助于显着降低摩擦力。除了，