Study On Drilling Force Of Cortical Bone Based On Micro-textured Tool

On the one hand,with the further combination of bionics and tribology,the study of micro-textured tools shows that micro-texture can improve the friction between the cutting tool and the chip,reduce tool wear,improve the surface quality and prolong tool life,apply more and more widely in the field of mechanical processing.On the other hand,in the virtual surgery system,the trainee can simulate the tactile force through the force feedback workbench,so that the trainee feels like doing the real surgery,repeated operation exercises,thus strengthening the trainee’s surgical skills,and improve the success rate of surgery.Based on these two points,this paper applies micro-texture to the surface of medical twist drill.Firstly,the axial force and torque in drilling process are studied by 3D modeling.Micro-pit depth,micro-pit diameter,micro-pit spacing are numerically studied,and the prediction model of axial force and torque are obtained.The main contents are as follows.1、The principle and the construction of three-dimensional drilling model of cortical bone drilling.This paper describes the drilling principle in detail,and divide drilling process into three sections;Establishing drilling simulation model of cortical bone and micro-texture bit,simulating the process of cortical bone drilling,and analyzing the stress deformation and the change of drilling force and torque during the drilling process.2、Study on Laser Machining Technology and Fabrication of Micro-textured Cutting Tools.The effects of marking times,pulse frequency and output power on the depth and diameter of the micro-texture are analyzed.The mathematic model is also established by using Matlab to fit the experimental results.The laser processing experiment is also carried out,and the results are analyzed.Finally,we design micro-texture twist drill for bone drilling test,and select reasonable processing parameters to prepare micro-textured medical twist drill.3、 Experimental Study and Simulation Model Verification of Bone Drilling.The cortical bone drilling test is designed and the micro-texture medical twist drill is used to perform bone drilling test.Kistler 9257 B three-axis dynamometer is used to record the changes of drilling force and torque during the drilling process.The experimental results and simulation results were analyzed and compared.4、Effect of Micro-texture Size Parameters on Drilling Force and Torque.The influence of micro-structure parameters on the axial force and torque is analyzed and studied,and the prediction model of axial force and torque on micro texture parameters are obtained.