Simulation And Experimental Study On Optimization Of Structure And Cutting Parameters Of Welded PcBN Turning Tool

Polycrystalline cubic boron nitride(PcBN)cutters are often used in high speed cutting of cast iron and hardened steel due to their high machining accuracy and good surface quality.Adding non-stoichiometric binder to PcBN material can obviously improve the mechanical properties of traditional PcBN material.At present,there are relatively few reports on the simulation and cutting of this new material.Based on the new non-stoichiometric PcBN composites developed by our group,this paper establishes the material model,uses DEFORM-3D software to simulate the cutting of 45 Quenched Steel Cylindrical surface,optimizes the cutting angle and cutting parameters through orthogonal experiments,screens the better performance turning tools and cutting parameters,and manufactures the corresponding welding turning tools for cutting experiments.Then the performance of the new turning tool is evaluated and the rationality and reliability of the simulation results are verified.Firstly,the cutting performance of the common 35 ~90 tool tip angle turning tool is simulated.By comparing the temperature field,stress field and cutting force,the cutting performance of the 60,75,80 and 90 tool tip angle turning tool is better.The orthogonal simulation is used to further optimize the angles and cutting parameters of the four welding turning tools.The optimal cutting angles of the turning tools with 60,75,80 and 90 degrees are obtained.The cutting temperature and main cutting force of the turning tool with 90 degrees are relatively low when the front angle is 0,the rear angle is 10,the main deviation angle is 40,the arc radius of the tool tip is 0.5 mm and the blunt radius is 0.1 mm.Secondly,by using the optimized cutting parameters and orthogonal simulation to optimize the cutting parameters of 60,75,80 and 90 degrees tool-tip turning tools,three factors of the optimal cutting parameters of tool durability and cutting parameters of the optimal processing quality are obtained,90 degree tool-tip turning tool at cutting speed of 60 m/min,feed of 0.05 mm/r,back feed of 0.15 mm turning tool at cutting speed of 60 m/min.The workpiece has good durability.When the cutting speed is 250 m/min,the feed rate is 0.10 mm/r and the back feed rate is 0.25 mm,the workpiece quality is better.By comparing the optimized 50 vol.% and 80 vol.% PcBN turning tools,it is concluded that the higher the content of CBN,the lower the turning temperature.Finally,the simulation results show that the average main cutting forces of 60,75,80,and 90 tool tip angle turning tools are 9% different from the actual cutting values.According to the optimized parameters,a 35 ~90 Comparing the hardness and surface roughness of the workpiece before and after processing,it is concluded that the hardness of the workpiece after processing increases slightly,and the degree of work hardening is positively correlated with the cutting force,but has nothing to do with the content of PcBN.The material performance of our research group is superior to that of manufacturer,and the wear area of turning tool with 60 and 90 sharp angle is superior to that of standard structure.