The Study of the Effect of Pre-Existing Residual Stress in Rough Hard Turning on New Residual Stress in Dry SuperfinishHard Turning

9612022刘氏硬车削是一种有吸引力的成形、车削、硬化、磨削和超精加工等传统精密加工实践的替代方案，因为可以省去几个工艺步骤。然而，由于缺乏知识以及热损伤和残余应力的风险，实现这一诱人的结果一直受到限制。该项目的目标是了解和模拟：先前存在的残余应力如何影响后续的残余应力和切屑形成，以及切割条件和进给深度比如何影响残余应力。这项研究将同时涉及数学建模和实验。一个实验设计矩阵，重复两次，将用来评估3个后刀面磨损水平、2个进给量、2个切割深度、2个切割速度和2个刀尖半径的影响。采用X射线衍射法测量残余应力，并采用Tay等的实验方法。艾尔用于确定温度分布。这将由使用有限元方法的建模工作来补充，以基于加工的热-机械模型来预测残余应力。该项目的成功可能会消除轴承等精密部件生产中冗长且成本高昂的工序，如精磨和超精加工。这意味着在保持质量的同时提高生产率。

9612022 Liu Hard turning is an attractive alternative to the conventional precision machining practice of forming, turning, hardening, grinding and superfinishing, because several process steps can be eliminated. However, achieving this attractive result has been limited by lack of knowledge and the risk of thermal damage and residual stresses. This project's objectives are to understand and model: how pre-existing residual stresses affect subsequent residual stresses and chip formation, and how cutting conditions and the ratio of feed to depth of cut affect residual stresses. This investigation will involve both mathematical modeling and experiment. An experimental design matrix, replicated twice, will be used to assess the effects of 3 levels of flank wear, 2 feeds, two depths of cut, 2 cutting speeds and 2 tool nose radii. X-ray diffraction will be used to measure residual stress, and the experimental method of Tay et. al. used to determine temperature distributions. This will be complemented by a modeling effort using the finite element method to predict residual stresses based on a thermal-mechanical model of machining. Success in this project potentially eliminates lengthy and costly operations like finish grinding and superfinishing, in the production of precision components like bearings. This means higher productivity while maintaining quality.