超硬工具椭圆轮廓的数控修整行走轨迹研究.pdf

摘要

超硬质工具加工技术已经有了一段比较长时间的历史，其中多以金刚石加工技术为主要研究对象。金刚石具有许多优异的性能 ,硬度高 ,耐磨性好 ,化学性能稳定。因此 ,它是一种非常有用的工业材料。它可以用于汽车航空航天，石油、地质、机械、电缆等行业中 ,用它制成的刀具寿命通常比硬质合金刀具高100 倍 ,具有很高的经济价值。

针对圆弧形金刚石砂轮精密修整的操作困难和装置复杂的问题，提出一种新的数控对磨成形修整方法。在该成形修整中，金刚石砂轮被驱动沿着圆弧插补运动轨迹与GC 磨石对磨，逐渐形成砂轮的圆弧形轮廓，用于超硬材料的曲面磨削。在建立砂轮圆弧形轮廓的数控修整模式的基础上，分析定位误差与修整形状偏差的关系。此外，建立修整精度和修整率的评价指标，进行正交试验，研究修整工艺参数，即砂轮转速、行走速率和进给深度，对修整精度和修整率的影响。在该数控对磨成形修整中不同半径的砂轮圆弧形轮廓能够被修整成形，可用于不同曲率的曲面磨削，从而研究出砂轮在加工过程中的精确行走轨迹路径。通过MATLAB软件程序设计，利用离散法将自由曲面进行离散并可视化，也可以将砂轮行走轨迹编成数控磨床可使用的G 代码。这种方法可以大幅度节约自由曲面的加工路径的设计时间和降低实验加工成本。

关键词：超硬质工具加工，金刚石加工，MATLAB 软件程序设计，离散法，G 代码

Abstract

Diamond processing technology of quality tools has quite a long time history,mostly diamond processing technology as the main object of study.Diamond has many high-performance, high hardness, abrasion resistance, and chemical properties and stability. So, it is a very useful industrial materials. It could be used in automotive to aerospace, petroleum, geology, machinery, cable and other industries, The tool life is 100 time bigger than carbide tool, so it has high economic value.

Due to the operation difficulty and equipment complexity of precision form truing shaped diamond grinding wheel，a new NC mutual—weal form truing was proposed．In this form truing，wheel is driven along arc interpolation path to grind GC stone and then arc—shaped wheel profile is gradually formed．It is used for curve grinding of super-hard materials．On the base of establishing control mode of formation radius of arc—shaped diamond grinding wheel，effect of wheel position error relative to GC stone was analyzed on form of trued arc—shaped profile of grinding wheel．In addition, evaluation indexes of truing accuracy and truing ratio were intruded，and then truing accuracy and truing ratio were investigated by orthogonal lest with reference to wheel rotate speed, moving speed and depth of cut. The dressing on the grinding wheel with different radius arc-shape contour can be trimmed, can be used for different curvature of the surface grinding. To work out the exact trajectory of path during the wheel processing. Designed by MATLAB software program, using the discrete method to discretize the free surface and visual, can also be compiled into CNC grinding wheel by using G-code, This approach can significantly save the processing path of free-form surface design time and reduce processing cost experiment.

Keyword: diamond grinding wheel, Diamond processing, MATLAB software program,discrete method, G-code