圆弧形砂轮精密修整及其声发射在线监测技术

针对球面、非球面及自由曲面超精密磨削加工用圆弧形金刚石砂轮难以精密修整的问题，提出基于旋转绿碳化硅（GC）磨棒的端部在位精密修整方法及修整过程的声发射在线监测技术。基于圆弧形金刚石砂轮的结构特性，制订圆弧形金刚石砂轮的在位精密修整与修整过程的声发射在线监测技术方案。依据修整与在线监测方案，对D64圆弧形金刚石砂轮进行修整实验及其声发射信号采集，修整后跳动误差小于10μm，比修整前减小30μm左右，砂轮精度显著提高。利用声发射信号均方根值获取砂轮修整结束的特征预警阈值，实现了旋转GC磨棒端部在位精密修整过程的在线监测以及修整结束时间的准确判断，可以有效提高球面非球面磨削加工过程的效率。

Precision Truing of Arc-shaped Diamond Wheel and On-line Monitoring of Truing Processes by AE Signals

To realize the efficient and precision truing of arc-shaped diamond wheels for ultra-precision grinding spherical, aspherical and freeform surfaces, a novel on-machine precision form truing of arc-shaped diamond wheels was proposed utilizing rotary GC rod. On-line monitoring of the truing processes by AE was studied. Based on the structural properties of arc shaped wheel, the technical solutions of truing and monitoring were formulated for D64 wheels. The run-out errors after truing are below 10μm which is reduced about 30μm before truing, the form accuracy of wheels was improved remarkably. The AE signals were processed to monitor the truing processes, and the Arms threshold for judging the finishing truing time was obtained. The monitoring technology will improve efficiency of the truing and grinding processes.