Grooving, conditioning and micromechanics of grinding wheels

研磨是一种战略性的制造过程；加拿大航空航天、汽车、石油天然气和林业行业都是研磨技术的用户。几乎所有由坚硬材料制成的零件，都需要精细的表面光洁度或严格的公差才能研磨。进行磨削研究的基本困难之一是缺乏对刀具几何形状的了解。砂轮有许多几何上未定义的切削点，这些切削点不规则地分布在其工作表面上，并以随机的方向呈现在工件上。在进行任何磨削操作之前，需要用金刚石工具对砂轮表面进行修整，以磨削砂轮并确保其具有圆形横截面。这一操作改变了砂轮上的刃口数量和大小，并显著影响了磨削过程。精细的修整条件会产生非常光滑的表面，但也会导致高力、高功耗和高可能性的低能效，而粗修整条件则会产生相反的效果。虽然已经通过测量工件表面粗糙度、磨削功率、力和温度来间接研究砂轮修整的影响，但砂轮表面形貌和这些结果之间的联系还没有得到充分的量化，因为没有一种技术可以完全和准确地定义砂轮上的所有刃口。因此，拟议研究的第一个目标是开发一种测量系统，该系统首次能够完全绘制工业尺寸砂轮的整个表面。这些信息将被用来提高磨削过程的成本效益和生产率，就像学习刀具几何形状如何影响车削和铣削使这些制造过程受益一样。接下来，将开发一种名为砂轮开槽的新型、廉价的砂轮修整技术，该技术可以有选择地改变砂轮表面，并以较低的能量和较高的材料去除速度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.