Temperature Modeling And Simulation Analysis Of Tool And Workpiece In Screw Thread Milling Process

The whirlwind milling has the characteristics of high efficiency,high precision and green pollution-free,and the thread screw is widely used in ships,power stations,highgrade numerical control machine,high-speed transport and aerospace,etc.The screw thread whirlwind milling has obvious differences from ordinary intermittent cutting and continuous cutting in terms of cutting heat source,heat transfer and thermal load.To control the cutting speed to reduce the cutting temperature and to suppress the thermal load impact of the screw thread whirlwind milling,It is of great theoretical significance and application value to explore the cutting temperature variation of the tool and the workpiece in the process of screw thread whirlwind milling.The paper takes the whirling milling as the research object,adopts the PCBN arc tool and the GCr15 workpiece material,and uses the cutting principle and heat transfer theory,and establishes the temperature model of the tool and workpiece.The temperature of the tool and the workpiece change under different conditions in the whirling milling process is researched,and the effects of cutting and non-cutting processes on tool and workpiece temperature are explored.The main research content is as follows:Firstly,on the basis of the analysis of the movement mechanism of whirlwind milling tool and workpiece and the dual arc characteristics of the tool,using the coordinate conversion relationship between the previous and subsequent cutting paths,the chip thickness,tool chip contact length during the thread milling process and the time-varying characteristics are analyzed.On this basis,the heat source area of the shear surface and the tool friction surface is established,and then the heat source strength of the shear surface and the heat intensity of the tool friction surface are solved to provide basis for modeling tool and workpiece temperature.Secondly,based on the cutting into and cutting out of the workpiece intermittently,the theoretical prediction model of the transient cutting temperature of the tool is established.The transient temperature of the tool is analyzed according to the superposition principle of the temperature field,and the influence of the cutting stage and the non-cutting stage on the tool temperature during the cutting process is taken into consideration,and the milling process is revealed.The periodic variation of the cutting tool under different cutting conditions is verified by the experiment.Then the change characteristics of the tool at different heat source frequencie and the distribution of the temperature under different depth are analyzed.Thirdly,based on the moving heat source method,the theoretical prediction model of the transient cutting temperature of the workpiece in the process of cyclone milling is established.The influence of the cutting stage and the non-cutting stage on the workpiece temperature in the cutting process is considered,and the influence of the cutting temperature on the workpiece temperature distribution under different processing conditions is revealed,and the influence of the cutting parameters on the workpiece temperature and The distribution and variation rule of workpiece under different depths are analyzed.Finally,the MATLAB tool is used to develop a temperature simulation analysis system for the whirlwind milling tool and workpiece.The structure and function module of the simulation system are designed.The system can be used to simulate the temperature of the tool and the workpiece under different cutting parameters.