Research On Cutting Force And Surface Quality Of High-speed Milling Hardened Steel

As an advanced manufacturing technology, high speed machining developed rapidly in recent years, with the unparalleled advantages over traditional CNC machining. Milling instead of grinding processing provides an effective way to effectively solve the problem of processing hardened steel materials, and gradually becomes the important support for the Advanced Manufacturing Technology. Milling process is more complex, so it is hard to get a good progress with the original method to study the of processing and cutting technology of materials difficult to cut. With the improvement of computer property and the promotion of the research measures, to use the computer simulation technology for the simulation and study of the milling process is possible. Milling of9CrWMn is studied in this paper, and the negative chamfer angle of PCBN cutting tools is chosen studied.Since we have only one set PCBN cutting tools with one negative chamfer angle in experiment, thence in this paper, with the combination of simulation and experimental research, theoretical and experimental study of the law in high-speed milling of hardened steel milling force, surface roughness and the chip with the cutting parameters change. And determined the suitable negative angle for processing. The content of the paper includes three aspects:1. A finite element model of the milling process is established based on DEFORM-3D. The Elastic stage and the plastic stage of cutting process are analysed in this paper. The material constitutive models, material separation criteria, and the contact and friction characteristic between the tool and chips and grid re-division are all described and determined in this paper. The steps of the cutting simulation process are introduced in detail. Milling process has been simulated with the Deform-3D software, and the changes of milling forces in the cutting process are also analysed.2. Experiments on high-speed milling are carried out on the HAAS CNC machine. During the experiments, the PCBN tool with negative chamfer angle is used to mill hardened9CrWMn. And cutting force signal is obtained with the orthern dynamometer. According to the data from the high-speed milling experimental, comparison of the finite element simulation results with experiment results showed the simulation results is resonable. The surface roughness of workpiece is measured in the experiment, chips are observated, and the impact of milling parameters on which are analysed.3. For compensation the lack of experimental conditions, in simulation, tools with the different negative chamfer are selected angle to study the impact of different negative chamfer angles on tool stress during milling process. In the final, the change trends of tool cutting force in the milling process is analysed, in order to obtain a better negative chamfer angle.