| With the rapid progress of science and technology,For the needs of micro-featured parts in the military,aerospace,medical equipment and other manufacturing fields has increased significantly.Because micro-milling technology has the characteristics of high efficiency,high flexibility,and high aspect ratio structures,micro-milling Tool technology has become a research hotspot in the field of micromachining.Titanium alloy TC4,as a typical difficult-to-machine material.Because of its excellent comprehensive properties such as high temperature resistance and corrosion resistance,so it has been widely applied in the industrial field.Compared with traditional milling cutters,the overall size of the micromilling cutter and the diameter of the cutter head are small,the rigidity and overall strength of the cutter are not high,and it is prone to breakage.The machining mechanism also has great characteristics.This article takes the micro-milling cutter for machining titanium alloy TC4 as the research object.The difference between micro-cutting mechanism and traditional cutting mechanism is discussed based on the finite element method.The structure optimization design of micro-milling cutter with a diameter of 0.1 mm and related research are carried out.First,based on the Deform simulation experimental platform,a two-dimensional orthogonal cutting model is established to perform a finite element simulation of the micro-cutting titanium alloy TC4 process,obtain a stress cloud diagram,extract cutting force data,analyze the chip morphology corresponding to different cutting depths,and discuss the cutting depth Effect on the minimum cutting thickness and size effect.By extracting the node displacement vector distribution of the workpiece material during stable cutting and using the node displacement method,the relationship between the cutting depth of the micro-cutting titanium alloy TC4 and the cutting edge arc radius at different cutting edge arc radii is obtained,and a comparison is set by setting The experimental simulation data,based on the changes in the equivalent stress,cutting force and cutting specific energy under the condition of small depth of cut,verified the size effect phenomenon in the micro-cutting process.By using the solidworks modeling platform to establish a three-dimensional model of micro-milling cutters with the same diameter and different blade structures,import the Deform-3D simulation module to study the influence of blade structure on cutting force and cutting temperature.Taking micro-milling cutters with a diameter of 0.1mm as the research object,through the establishment of single-factor experiment and orthogonal experimental cutting scheme,the main influence of micro-milling cutter structure parameters and processing technology parameters on cutting force and cutting temperature was studied.Reducing the milling force is the goal to obtain the optimal combination of the three factors,and based on the response surface method to obtain the micro-milling cutter geometric parameters interactive influence law.It is verified that the micro-milling process also has the size effect phenomenon affected by the minimum feed per tooth.The finite element ANSYS Workbench was used to perform static and dynamic mechanical analysis on the micro-milling cutter model.The influence of the cutting edge shape,tool overhang and cutting edge length-diameter ratio on the tool modal was studied.In the actual machining process,the tool overhang should be controlled within the range of 15mm-20 mm,and the length-to-diameter ratio of the cutting edge is less than 4;the connection between the blade neck and the root of the blade head is optimized,and the maximum equivalent stress is used as the evaluation index to be optimized.After the structure can significantly reduce the stress concentration phenomenon,and thus proposed a new tapered neck structure micro-milling cutter,which can effectively increase the tool modal frequency and has better dynamic performance. |
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