CUTTING TOOL EDGE HONING USING NON-NEWTONIAN MEDIA

使用非牛顿介质的切削刀具刃口珩磨

• 批准号: 531967-2018
• 负责人: Koshy, Philip
• 金额: $ 1.82万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=655916
• 关键词: CUTTING; TOOL; EDGE; HONING; USING

The edges of metal cutting tools are commonly prepared to correspond to an approximately rounded shape of a**radius of several tens of micrometers, by a process known as edge honing. In addition to enhancing edge**strength, edge honing extends tool life, improves coatability and has a favorable influence on the quality of the**machined surface. Processes currently used for edge honing such as abrasive brushing and micro-blasting are**limited by the high variability in the geometry of the prepared edge, and their capability to hone cutting tools of**a complex geometry. To this end, this research project aims to develop an innovative, cost-effective and**environment-friendly edge honing process that has the potential to address the issues above. The novel process**that is to be developed is a free abrasive edge honing process wherein abrasives are suspended in a**non-Newtonian (shear-thickening) fluid that exhibits an appreciable change in its viscosity, depending on the**rate and mode of its deformation. A mixture of corn starch (~50% by weight) and water is one such fluid. The**medium behaves like a fluid at the lower end of strain rate, with the behavior approaching that of a solid with**an increase in strain rate. Such a dramatic change in fluid behavior is harnessed to control the force field that**engages abrasives against a tool edge, given that the change of state is rapid, reversible and controllable. In**consideration of such a fluid response, the process kinematics/geometry may be controlled in this novel process**to regulate the abrasive-workpiece interaction, and thereby the mechanism and extent of material removal. As**the edge honing medium is a fluid, cutting tools of an intricate geometry such as gear hobbing tools can further**be readily processed. The proposed work will entail the edge preparation of simple, straight edge tools to start**with, so as to understand process behavior; this will be followed by investigations on curved edge tools, and**will characterize its efficacy in the honing of high speed steel and superhard tools. Given the critical influence**of edge honing on the quality and performance of cutting tools, this research is expected to significantly**enhance the competitive edge of the industrial partner in the marketplace.

金属切削刀具的刃口通常通过称为刃口珩磨的工艺制备成对应于几十微米 ** 半径的近似圆形形状。除了增强边缘强度外，边缘珩磨还可延长刀具寿命，改善涂层性能，并对加工表面的质量产生有利影响。目前用于边缘珩磨的工艺，如磨料刷磨和微喷砂，受到制备边缘几何形状高度可变性的限制，以及它们珩磨复杂几何形状的切削工具的能力。为此，本研究项目旨在开发一种创新的，具有成本效益和环境友好的边缘珩磨工艺，具有解决上述问题的潜力。即将开发的新工艺 ** 是一种游离磨料边缘珩磨工艺，其中磨料悬浮在非牛顿（剪切增稠）流体中，该流体的粘度根据其变形的速率和模式而发生明显变化。玉米淀粉（约50重量%）和水的混合物就是这样一种流体。介质在应变速率较低时表现得像流体，随着应变速率的增加，介质的行为接近固体。流体行为的这种戏剧性变化被用来控制力场，该力场使磨料抵靠工具边缘接合，假定状态的变化是快速的、可逆的和可控的。考虑到这种流体响应，在这种新颖的工艺中可以控制工艺运动学/几何学，以调节磨料-工件相互作用，从而调节材料去除的机制和程度。由于边缘珩磨介质是一种流体，复杂几何形状的切削工具，如滚齿工具，可以更容易地加工。拟议的工作将需要简单的，直刃刀具的边缘准备开始 **，以了解过程行为;这将是其次是弯曲的边缘工具的调查，和 ** 将表征其在高速钢和超硬工具的珩磨效率。鉴于边缘珩磨对刀具质量和性能的重要影响，这项研究有望显着提高工业合作伙伴在市场上的竞争优势。