刀具表面不同角度正弦型沟槽织构的数值模拟与实验研究

目的 分析刀具表面正弦型沟槽织构不同角度对接触表面摩擦学性能的影响。方法 利用激光加工设备在硬质合金表面加工出与垂直线成0°、30°、60°、90°的正弦型沟槽织构，并利用有限元软件FLUENT对不同角度正弦沟槽织构内的润滑液压力等参数进行仿真分析，同时将表面带有织构的硬质合金与钛合金球进行摩擦磨损实验，并通过扫描电镜观察摩擦实验后的表面。结果 硬质合金表面四种不同角度的正弦沟槽织构均能降低与钛合金对摩时的摩擦系数，且随着速度的增大，四种织构表面的摩擦系数均出现不同程度的减小，其中90°的正弦沟槽织构在摩擦实验中的减摩效果最为显著，滑动速度为20 mm/s时，摩擦系数相对于光滑表面减小了77%。通过系列摩擦磨损实验结果表明，正弦沟槽织构产生动压效应的数值模拟结果与减摩降磨实验结果基本一致，刀具表面不同角度正弦沟槽织构产生动压润滑效果的显著程度为90°>30°>0°>60°。结论 与钛合金对摩中，硬质合金表面沟槽织构的存在对降低摩擦系数和减少磨损量具有重要意义，尤其是90°正弦沟槽织构的存在可以大幅改善硬质合金表面的摩擦学特性，其主要作用机理在于及时有效补充接触表面间的润滑液，并产生持续的动压润滑效应，建立并形成连续的摩擦接触界面间油膜，起到减摩降磨的作用。

Numerical Simulation and Experiment on Sinusoidal Grooved Texture with Different Angles on Tool Surface

The work aims to analyze the influence of sinusoidal grooved texture with different angles on tool surface on the tribological performance of contact surface. Sinusoidal grooved textures with 0°, 30°, 60° and 90° to vertical lines were fabricated on the surface of cemented carbide by laser processing equipment. The parameters like lubricant pressure, etc. in sinusoidal grooved textures with different angles were simulated and analyzed by finite element software FLUENT. At the same time, the friction and wear experiments of cemented carbide and titanium alloy balls with textures were carried out. The surface results after the friction experiment were observed by scanning electron microscope. The sinusoidal grooved textures with four different angles on the surface of cemented carbide could reduce the friction coefficient with titanium alloy, and with the increase of sliding speed, the friction coefficient of four types of cemented carbide textured samples decreased in varying degrees. 90° sinusoidal textured sample had the most obvious antifriction effect, and the friction coefficient decreased by 77% compared with smooth sample. At the same time, a series of experimental results showed that the numerical simulation results of the sinusoidal grooved texture were basically consistent with the experimental results. The sinusoidal grooved texture with different angles on the tool surface produced different hydrodynamic lubrication effects, with a significance of 90°>30°>0°>60°. The existence of groove texture on the surface of cemented carbide is of great significance to reduce the friction coefficient and wear amount in the friction with titanium alloy. Especially, the existence of 90° sinusoidal groove texture can greatly improve the surface tribological properties of cemented carbide. The main mechanism is to replenish the lubricant on the contact surface effectively, and continuously produce the hydrodynamic lubrication effect, establish and form a continuous oil film between the friction contact interfaces, which can reduce friction and wear.