Li Guangxi, Xie Weibo, Wang Hongtao, Chai Yongbo, Zhang Shaolin, Yang Liquan
Henan Province Engineering Research Center of Ultrasonic Technology Application, Pingdingshan University, Pingdingshan 467000, China.
School of Intelligent Manufacturing and Transportation, Chongqing Vocational Institute of Engineering, Chongqing 402260, China.
Micromachines (Basel). 2023 May 25;14(6):1111. doi: 10.3390/mi14061111.
This study conducted longitudinal ultrasonic-assisted milling (UAM) tests and optimized a combination of milling technological parameters to achieve high-quality machining of TC18 titanium alloy. The motion paths of the cutter under the coupled superposition states of longitudinal ultrasonic vibration and end milling were analyzed. Based on the orthogonal test, the cutting forces, cutting temperatures, residual stresses, and surface topographical patterns of TC18 specimens under different UAM conditions (cutting speeds, feeds per tooth, cutting depths, and ultrasonic vibration amplitudes) were examined. The differences between ordinary milling and UAM in terms of machining performance were compared. Using UAM, numerous characteristics (including variable cutting thickness in the cutting area, variable cutting front angles of the tool, and the lifting of the cuttings by the tool) were optimized, reducing the average cutting force in all directions, lowering the cutting temperature, increasing the surface residual compressive stress, and significantly improving the surface morphology. Finally, fish scale bionic microtextures with clear, uniform, and regular patterns were formed on the machined surface. High-frequency vibration can improve material removal convenience, thus reducing surface roughness. The introduction of longitudinal ultrasonic vibration to the end milling process can overcome the limitations of traditional processing. The optimal combination of UAM parameters for titanium alloy machining was determined through the end milling orthogonal test with compound ultrasonic vibration, which significantly improved the surface quality of TC18 workpieces. This study provides insightful reference data for subsequent machining process optimization.
本研究进行了纵向超声辅助铣削（UAM）试验，并优化了铣削工艺参数组合，以实现TC18钛合金的高质量加工。分析了刀具在纵向超声振动与端铣耦合叠加状态下的运动轨迹。基于正交试验，研究了不同UAM条件（切削速度、每齿进给量、切削深度和超声振动幅值）下TC18试样的切削力、切削温度、残余应力和表面形貌。比较了普通铣削和UAM在加工性能方面的差异。采用UAM优化了众多特性（包括切削区域的可变切削厚度、刀具的可变切削前角以及刀具对切屑的抬起作用），降低了各个方向的平均切削力，降低了切削温度，增加了表面残余压应力，并显著改善了表面形貌。最终，在加工表面形成了图案清晰、均匀且规则的鱼鳞仿生微纹理。高频振动可提高材料去除便利性，从而降低表面粗糙度。将纵向超声振动引入端铣过程可克服传统加工的局限性。通过复合超声振动端铣正交试验确定了钛合金加工UAM参数的最优组合，显著提高了TC18工件的表面质量。本研究为后续加工工艺优化提供了有价值的参考数据。
