Grooving, conditioning and micromechanics of grinding wheels

磨削是一种战略性的制造工艺;加拿大航空航天、汽车、石油和天然气以及林业行业都是磨削技术的用户。几乎所有需要精细表面处理或严格公差的硬质材料制成的零件都经过研磨。进行磨削研究的基本困难之一是缺乏对切削刀具几何形状的了解。砂轮具有大量几何上不确定的切削点，这些切削点不规则地分布在其工作表面上，并且以随机取向呈现给工件。在任何磨削操作之前，需要通过用金刚石工具切割砂轮表面来调节砂轮的表面，以便锐化砂轮并确保其具有圆形横截面。该操作修改砂轮上的切削刃的数量和尺寸，并显著影响磨削过程。精细修整条件产生非常光滑的表面，但也导致能量效率低，力大，功耗高，工件损坏的可能性高，而粗修整条件具有相反的效果。虽然已经通过测量工件表面粗糙度、磨削功率、力和温度间接地研究了砂轮修整的效果，但是砂轮表面形貌与这些结果之间的联系尚未充分量化，因为不存在可以完全且准确地定义砂轮上的所有切削刃的技术。因此，所提出的研究的第一个目标是开发一种测量系统，该系统首次可以完全映射工业尺寸的砂轮的整个表面。这些信息将用于提高磨削工艺的成本效益和生产率，就像了解刀具几何形状如何影响车削和铣削使这些制造工艺受益一样。接下来，将开发一种称为砂轮开槽的新颖且廉价的砂轮修整技术，该技术可以选择性地改变砂轮的表面，并使用更少的能量以更高的材料去除率产生所需的表面粗糙度。

Grinding is a strategic manufacturing process; the Canadian aerospace, automotive, oil and gas, and forestry industries are all users of grinding technology. Virtually all parts made of hard materials that require fine surface finishes or tight tolerances are ground. One of the fundamental difficulties with conducting research in grinding is a lack of knowledge of the geometry of the cutting tool. A grinding wheel has a multitude of geometrically undefined cutting points which are irregularly distributed on its working surface and which are presented to the workpiece at random orientations. Prior to any grinding operation, the surface of a grinding wheel needs to be conditioned by cutting the wheel surface with a diamond tool in order to sharpen the grinding wheel and ensure that it has a circular cross-section. This operation modifies the number and the size of cutting edges on the grinding wheel and significantly affects the grinding process. Fine dressing conditions produce very smooth surfaces but also result in low energy efficiency with high forces, high power consumption and a high probability of workpiece damage, while coarse dressing conditions have the opposite effects. While the effects of wheel conditioning have been studied indirectly by measuring the workpiece surface roughness, grinding power, forces and temperatures, the link between the wheel surface topography and these outcomes has not been adequately quantified because a technology does not exist that can completely and accurately define all of the cutting edges on a grinding wheel. Thus, the first objective of the proposed research is to develop a measuring system that, for the first time, can completely map the entire surface of an industrial sized grinding wheel. This information will be used to improve the cost effectiveness and productivity of the grinding process in the same way that learning how tool geometry affects turning and milling has benefited those manufacturing processes. Next, a novel and inexpensive wheel conditioning technology called wheel grooving will be developed that can alter the surface of a grinding wheel in a selective manner and produce the desired surface roughness using less energy with higher material removal rates.