The Forecast And Research In The Process Of Turning

Cutting force is the main indicator that responds to the process of metal cutting. The research on cutting force can not only improve the efficiency and quality but there are great significance to understand cutting mechanism, compute power consumption, design machinery tools, cutting tools, fixtures and optimize the tool geometry parameters and so on. Therefore since the metal cutting appears it is the target for everyone who engaged in metal cutting to predict the force exactly. Building the cutting model, clarfying the influence factors and displines to cutting force to achieve the prediction of cutting force is an important task in the field of cutting theory. However due to multiple factors to cutting force metal cutting process is pretty complicatable, the result of traditional cutting model and formula is far away from practice which lead to poor universal application.With the rapid development of computer technology,the FEA method has become an important instruction to research and simulate in the field of cutting process.Therefore this thesis is based on the metal cutting theory,finite element modeling theory and solving method, which take the cutting force as the main content and made in-depth research on cutting process as well as cutting force prediction by combining theoretical analysis,finite element digital computation and experimental study.First,in light of metal-cutting theory and numerical simulation this thesis analyzed finite-element theory in the process of metal cutting and summarized the key technology of simulation systematically,including chip separation criteria, rigid-plastic flow equation,mesh distortion and remeshing,principle of virtual work and variational principle and so on.Then the thermal-elastic plastic finite modeling of oblique cutting model was built. Next other nonlinearity finite simulation key technology was also analysed such as finite element mesh model, material to constitutive, friction type between tool and cutting scrap and the heat-conduction equation which are referred in this thesis.At last the software deform was adopted to build the three-dimension finite element model of cutting tool with indexable inserts in which we choose cemented carbide insert and 45# steel,by utilizing the model we can not only get cutting force but also the curves of cutting force. By changing the cutting parameters and simulating several times,we can get the simulation curves of dynamic cutting force,and also by comparing the cutting force that obtained in different cutting parameters, the influence discipline of cutting parameters to cutting force can be obtained what provides useful data in researching the tool's cutting capacities. Finally, we adopt three-way multifunction load cell produced by Switzerland to do metal cutting experiment.After comparing the experimental result,simulation result and experimental formula.The data analysis show that:simulation prediction is accord with the experiment data,all factors that influence cutting force is consistent with cutting theory and it's accuracy is super than experiment.Thus we can conclude that the finite element model built in this thesis is correct and valid.The research result shows that: the application of finite element model to achieve predicting of cutting force can provide feasible measurement for researching new materal process ability and new techniques mechanism is quite significant for doing metal cutting research efficient and low cost.