Prediction of Cutting Forces, Tool Stresses, Temperatures and Tool Life in High Speed Machining

在高速高精度加工中，刀具与工件之间的相互作用是极其重要和复杂的。它们影响刀具寿命、工艺经济性和加工产品的表面完整性。为了理解这些相互作用，将使用基于有限元方法（FEM）的金属流模拟技术来确定工艺条件（进料速度、切削深度、切削速度）对切削力、刀具温度和应力以及刀具失效的影响。该项目包括以下任务：(1)将进行正交车削和铣削试验，以建立确定加工中遇到的高应变率、应变和温度条件下的流动应力数据的方法；(2)将开发一个计算机程序来预测三维实际加工过程中的力、应力和温度，如面铣、钻孔和球头铣；(3)验证磨损模型，以预测刀具在工艺变量、刀具材料和涂层作用下的磨损。基于切削过程物理的建模技术将用于演示如何估计刀具磨损，改进刀具和刀片设计，以及优化工艺条件。这个项目的结果有望对金属切削操作的基本理解做出重大贡献；并且，减少了在工业环境中建立和优化高速加工操作所需的实验量。

In high-speed and high-precision machining, the interactions between the cutting tool and the workpiece are extremely important and complex. They affect tool life, process economics, and surface integrity of the machined product. To understand these interactions, finite element method (FEM) based metal flow simulation techniques will be used to establish the effect of process conditions (feed rate, depth of cut, cutting speed) upon cutting forces, tool temperatures and stresses, and tool failure. The project consists of the following tasks: (1) Orthogonal turning and milling tests will be conducted to establish a methodology for determining the flow stress data under high strain rate, strain and temperature conditions encountered in machining; (2) A computer program will be developed to predict forces, stresses, and temperatures in three-dimensional practical machining processes such as face milling, drilling, and ball-end milling; and (3) A wear model will be validated to predict tool wear in function of process variables and tool material and coating. Modeling techniques based on the physics of the cutting process will be used to demonstrate how to estimate tool wear, improve tool and insert design, and optimize process conditions. The results of this project are expected to contribute significantly to the fundamental understanding of metal cutting operations; and, reducing the amount of experimentation needed to establish and optimize high speed machining operations in an industrial environment.