Guo Ce, Zhu Xijing
Shanxi Key Laboratory of Precision Machining, Taiyuan University of Technology, 030024 Taiyuan, China; Shanxi Key Laboratory of Advanced Manufacturing Technology, School of Mechanics and Power Engineering, North University of China, 030051 Taiyuan, China.
Shanxi Key Laboratory of Advanced Manufacturing Technology, School of Mechanics and Power Engineering, North University of China, 030051 Taiyuan, China.
Ultrasonics. 2018 Mar;84:13-24. doi: 10.1016/j.ultras.2017.09.016. Epub 2017 Sep 23.
The effect of ultrasound on generating and controlling the cavitation bubble of the grinding fluid during ultrasonic vibration honing was investigated. The grinding fluid on the surface of the honing stone was measured by utilizing the digital microscope VHX-600ESO. Based on analyzing the cavitation mechanism of the grinding fluid, the bubble dynamics model under conventional honing (CH) and ultrasonic vibration honing (UVH) was established respectively. Difference of dynamic behaviors of the bubble between the cases in UVH and CH was compared respectively, and the effects of acoustic amplitude and ultrasonic frequency on the bubble dynamics were simulated numerically using the Runge-Kutta fourth order method with variable step size adaptive control. Finally, the cavitation intensity of grinding fluids under ultrasound was measured quantitatively using acoustimeter. The results showed that the grinding fluid subjected to ultrasound can generate many bubbles and further forms numerous groups of araneose cavitation bubbles on the surface of the honing stone. The oscillation of the bubble under UVH is more intense than the case under CH, and the maximum velocity of the bubble wall under UVH is higher two magnitudes than the case under CH. For lower acoustic amplitude, the dynamic behaviors of the bubble under UVH are similar to that case under CH. As increasing acoustic amplitude, the cavitation intensity of the bubble is growing increased. Honing pressure has an inhabitation effect on cavitation effect of the grinding fluid. The perfect performance of cavitation of the grinding fluid can be obtained when the device of UVH is in the resonance. However, the cavitation intensity of the grinding fluid can be growing weakened with increasing ultrasonic frequency, when the device of UVH is in the off-resonance. The experimental results agree with the theoretical and numerical analysis, which provides a method for exploring applications of the cavitation effect in ultrasonic assisted machining.
研究了超声振动珩磨过程中超声对磨削液空化气泡产生及控制的影响。利用数字显微镜VHX - 600ESO对珩磨石表面的磨削液进行测量。在分析磨削液空化机理的基础上，分别建立了普通珩磨（CH）和超声振动珩磨（UVH）下的气泡动力学模型。分别比较了UVH和CH工况下气泡动力学行为的差异，并采用变步长自适应控制的四阶龙格 - 库塔法对声幅和超声频率对气泡动力学的影响进行了数值模拟。最后，使用声强计对超声作用下磨削液的空化强度进行了定量测量。结果表明，受超声作用的磨削液会产生许多气泡，并在珩磨石表面进一步形成多组蛛网状空化气泡。UVH下气泡的振荡比CH下更强烈，UVH下气泡壁的最大速度比CH下高两个数量级。对于较低的声幅，UVH下气泡的动力学行为与CH下相似。随着声幅增加，气泡的空化强度不断增大。珩磨压力对磨削液的空化效果有抑制作用。当UVH装置处于共振状态时，磨削液可获得理想的空化性能。然而，当UVH装置处于非共振状态时随着超声频率增加，磨削液的空化强度会不断减弱。实验结果与理论和数值分析结果一致，为探索空化效应在超声辅助加工中的应用提供了一种方法。
