Research on tool wear and compensation to improve contour accuracy in precision machining of thin-walled curved components
摘要
The thin-walled spherical shell made from 45# steel is a crucial component in high-end equipment fields such as precision physical experiments, aerospace, and national defense. Tool wear is a key factor that determines the high contour accuracy of these spherical shells. During the precision machining of spherical shells, the cutting edge radius (rn) and the cutting depth (ap) are of comparable magnitudes, making the cutting depth highly sensitive to changes in the cutting edge radius. Furthermore, as the tool-workpiece contact (TWC) zone continuously changes, the tool wear under this working condition is more complex. This paper takes the 45# steel thin-walled spherical shell as the research object, aiming to study the tool wear characteristics when rn≈ap. We also explore tool wear compensation methods to improve the contour accuracy of the spherical shell. Based on the relationship between rn and ap, we analyze the chip formation mechanisms in precision cutting and develop a TWC movement model during shell machining, which enables the prediction of the shape of tool wear bands. Furthermore, we conduct tool wear experiments to validate the accuracy of the model. Through a quantitative analysis of the relationship between cutting edge degradation and machining errors, we ascertain that tool wear contributes approximately 40% to the machining error. Additionally, we propose a compensation method for tool wear in the precision machining of thin-walled spherical shells based on the maximum degradation of the cutting edge. Experimental results demonstrate that this compensation method can effectively improve machining accuracy by approximately 50%. This study provides actionable insights and a theoretical foundation for high-performance manufacturing processes of thin-walled curved components at the tool wear level, demonstrating significant engineering application value.