骨组织微创切削微细铣刀设计制备及铣削实验研究

Design and Fabrication of Micro-end Mills for Minimally Invasive Milling of Bone Tissue

针对医疗骨组织微创切削用超小直径微细铣刀的特殊需求,开展了异形结构微细铣刀结构优化设计研究。设计并制备了直径50μm的螺旋形、□形和△形3种超小直径微细铣刀,并对比研究其切削性能。分析不同形状的微细刀具几何结构特征,对微细铣刀进行静力学仿真分析,研究不同几何结构对微细铣刀刚度和强度的影响;分析3种微细刀具精密刃磨方法和刃磨质量;开展骨组织微创切削微细铣刀切削实验,对骨组织微细切削形貌进行检测,对比分析不同刀具对骨组织切削质量的影响。实验结果表明:在微细铣刀切削骨组织实验中,螺旋形微细铣刀在切削过程中过早地发生了刀具的整体折断,△形和□形铣刀能够进行长时间切削;△形铣刀切削的沟槽毛刺和崩边较小,表面质量明显优于其他刀具,更适合骨组织微创伤切削。

For the special requirement of ultra-small micro-end mill for minimally invasive milling of bone tissue,the structural optimization design of special-shaped micro end mills is studied.Three kinds of micro-end mills(helical-shaped,△-shaped and□-shaped)with diameter of 50μm were designed and manufactured,and their milling performances were also investigated.The geometric structures of micro-end mills with different shapes are analyzed,and the static analysis of the mills is conducted to study the effect of geometric structure of micro-end mill on its stiffness and strength.The precision milling method and milling quality of three kinds of micro-end mills are investigated.The bone tissue minimally invasive milling experiments using ultra-small micro end mills were carried out,and the morphologies of milled bone tissues were observed.The milling quality of bone tissue workpiece was analyzed.In the process of bone tissue micro milling,the helical-shaped micro-end mill is prematurely fractured,△-and□-shaped micro-end mills can cut for long time.For the△-shaped micro-end mill,the machined grooves have small burr width and edge collapse,and higher surface quality.The△-shaped micro-end mill is more suitable for minimally invasive milling of bone tissue.