低频振动对塑性成形表面微观形貌的影响

目的 通过对塑性成形界面施加纵向和法向低频振动，探究不同振动参数对成形过程中表面质量的影响规律。方法 采用自主设计的低频振动发生器完成纵向振动作用下的摩擦实验和法向振动作用下的压缩实验，统计材料表面变形区域的平均粗糙度，评价成形质量。结果 在干摩擦条件下，不同频率(0~50 Hz)的纵向小振幅(0.1 mm)振动有利于提高成形界面的表面质量，变形区域的表面粗糙度与频率成反比，但是较大振幅(0.4 mm)的纵向振动会增加接触面的材料磨损，降低表面质量;不同频率(0~50 Hz)和不同振幅(0~0.4 mm)的法向振动均有利于提高干摩擦成形界面的表面质量，在0.2 mm振幅条件下表面粗糙度下降最为明显，振幅超过0.2 mm后，增加振幅对提升表面质量的影响不明显。结论 低频振动对成形界面微观形貌影响较大，合理优化低频振动工艺参数可显著提高成形界面的表面质量。

Effect of Low-frequency Vibration on the Microstructure of Plastic Forming Interface

The work aims to study the effect of different vibration parameters on the surface quality during forming by applying longitudinal and normal low-frequency vibration on the plastic forming interface. The independently designed low-frequency vibration generator was used to complete the sliding experiment under the action of longitudinal vibration and the compression experiment under the action of normal vibration, and the average roughness of the deformation area was calculated to evaluate the forming quality. Under the condition of dry friction, different frequencies (0-50 Hz) of longitudinal vibration with small amplitude (0.1 mm) were beneficial to improving the surface quality of the forming interface, and the surface roughness of the deformation area was inversely proportional to the frequency, but the longitudinal vibration with larger amplitude (0.4 mm) increased the material wear of the contact surface and reduced the surface quality. Different frequencies (0-50 Hz) of normal vibration with various amplitudes (0-0.4 mm) were conductive to improving the surface quality of forming interface under dry friction. The surface roughness decreased most obviously when the amplitude was 0.2 mm, but when the amplitude exceeded 0.2 mm, the effect of increasing the amplitude on improving the surface quality was not obvious. Low-frequency vibration has a great effect on the microstructure of the forming interface, and reasonable low-frequency vibration process parameters can significantly improve the surface quality of the forming interface.