Inverse cutting technology - a new strategy in face milling

该提案基于正在运行的项目GZ：(去除符号)，旨在通过提高端面铣削的生产率来改善工艺稳定性。这是通过减小切割比b/h(未变形切屑宽度b到未变形切屑厚度h)来实现的。如果实现b/h&lt；1的低切削率策略，许多切割参数和机构都是颠倒的。它可以被称为“逆”切割技术。通过调整切削参数(减小切削深度Ap，增加每齿进给量Fz)达到最低切削率，使加工过程稳定。随着切削率的减小，倾斜力矢量的方向向主轴方向偏转。因此，较低的切削率对加工动力学有积极的影响。该项目的目标包括基础研究中的主题，即反向切削率对铣削过程中切削力、过程动力学和过程温度的影响，以指导实际的工艺和刀具设计。主要的里程碑是用于计算过程力、刀具变形和残余应力的模型的发展，阶梯切割和刀具刃的螺旋定位的研究，Kienzle力模型的扩展，微观和宏观刀具几何的设计，反向切割时切割速度对表面完整性的影响的研究。最后，反向切屑形成和高速切割相结合的目的是在表面完整性和生产率方面显著优化端面铣削过程。

The proposal based on the running project GZ: (sign removed) aims to improve process stability at increasing productivity in face milling. This is realised by reducing the cutting ratio b/h (undeformed chip width b to undeformed chip thickness h). If the strategy of low cutting ratio is realised up to b/h < 1, many cutting parameters and mechanisms are inverted. It can be referred to as “inverse” cutting technology. Adapting cutting parameter (decreasing the depth of cut ap and increasing the feed per tooth fz) to the lowest cutting ratio, the cutting process is stabilized. With decreasing cutting ratio the direction of the declination force vector turns towards the spindle axis. Accordingly, a low cutting ratio has a positive effect on process dynamics.The project objective contains topics from basic investigations on the effect of the inverse cutting ratios on cutting force, process dynamics and process temperature in milling, which are leading to practical process and tool design. The main milestones are the development of models for calculation of process forces, tool deflection und residual stresses, investigations on stepped cutting and helical positioning of the cutting edges, extension of the Kienzle force model, design of micro and macro tool geometry, investigation on cutting speed influence on surface integrity at inverse cutting. Finally, the combination of inverse chip formation and high-speed cutting is intended to significantly optimize the face milling process in terms of surface integrity and productivity.