Study on the mechanism of burr formation in ultrasonic vibration-assisted honing 9Cr18MoV valve sleeve

The precision, lifespan, and stability of the electro-hydraulic servo valve sleeve are significantly impacted by the edge burrs that are easily created when honing the valve sleeve. The existing deburring process mainly rely on manual operation with high cost and low efficiency. This paper focuses on reducing the burr size during the machining process. In this paper, a single-scratch test with a finite element simulation model is conducted to study the mechanism of burr generation. The tests were carried out under ultrasonic vibration and non-ultrasonic vibration conditions to explore the effect of ultrasonic vibration on burrs. Besides, a honing experiment is conducted to verify the conclusions. The results at various cutting parameters are analyzed, and the mechanism of burr generation is revealed. The stiffness lacking of the workpiece edge material is the main reason for the burr generation. The cutting depth shows a significant effect on burr size while the cutting speed does not. The inhibition mechanism of ultrasonic vibration on burrs is also revealed. The separation of the burr stress field under ultrasonic vibration and the higher bending hinge point is the reason for burr fracturing. The re-cutting effect of ultrasonic vibration reduces the burr growth rate. The results of the honing experiment verified these conclusions and obtained a combination of honing parameters to minimize the burr growth rate.