硬质合金球头铣刀微织构制备及其铣削行为动态演变

The micro-texture with the high performance of antifriction, anti-adhesion and improvement of wearing capacity is processed on the cutting tool, which is helpful to improve the cutting performance and improve the surface integrity of the titanium alloy. It has become one of the effective ways to achieve the high efficiency and high quality machining of titanium alloy. This project is based on the laser fabrication technology of cemented carbide micro-textured surface, the preparation precision of the micro-texture is improved, and the influence laws of the laser processing on the properties of cemented carbide materials are studied, which reveals the mechanism of anti-wear and anti-friction. The influence laws of distribution density of the micro-texture on antiwear and antifriction properties are analyzed. A model of variable distribution density of the micro-texture is established. The limit cutting depth and critical cutting depth is study for determining the position of the micro texture.The dynamic evolution of milling behavior is comprehensively expounded considering placement mode, distribution characteristics and parameters of the micro-texture. The evaluation model of workpiece surface integrity is established, and the design criterion of mesoscopic geometric characteristics of flank face is put forward. Based on this, the design of the micro-texture ball end milling tool is optimized, which provides important theoretical and technological basis for reducing tool wear and improving machining quality in finishing process of titanium alloy.

在刀具上置入高性能的具有减摩、抗粘附作用的微织构，能有效改善刀具切削性能，提高工件表面完整性，已成为解决钛合金高效、高质量加工的有效途径之一。本项目以硬质合金表面微织构的激光制备技术为切入点，提高微织构的制备精度，研究激光加工工艺对硬质合金材料性能的影响规律，揭示微织构的抗磨减摩机理；对比分析微织构分布密度对刀具抗磨减摩性能的影响规律，建立变密度微织构分布设计模型；研究微织构作用位置变化的极限切深和临界切深域，从织构置入方式、分布特征、尺寸参数等方面全面阐述刀具铣削行为的动态演变规律；建立工件表面完整性评价模型，提出刀具后刀面介观几何特征设计准则，优化微织构球头铣刀设计，为降低钛合金精加工条件下刀具磨损，提高加工质量提供重要理论依据和技术基础。

在刀具上置入高性能的具有减摩、抗粘附作用的微织构，能有效改善刀具切削性能，提高工件表面完整性，已成为解决钛合金高效、高质量加工的有效途径之一。本项目以硬质合金表面微织构的激光制备技术为切入点，以提高微织构的制备精度为目的，研究了激光加工工艺对硬质合金材料性能的影响规律，揭示了微织构的抗磨减摩机理；对比分析了微织构分布密度对刀具抗磨减摩性能的影响规律，建立了变密度微织构分布设计模型；研究了微织构作用位置变化的极限切深和临界切深域，从织构置入方式、分布特征、尺寸参数等方面全面阐述了刀具铣削行为的动态演变规律；建立了工件表面完整性评价模型，提出了刀具后刀面介观几何特征设计准则，优化了微织构球头铣刀设计，为实现精加工条件下钛合金高效铣削提供了扎实的理论依据和实验基础。. 项目研究结果表明微织构激光制备切实有效，通过优化激光加工工艺参数使得微织构的加工质量、尺寸和形貌可以得到保证；激光制备微织构时会使Co元素析出，可提高刀具硬度，提高刀具抗磨性能；微织构的置入可以减小刀-屑接触长度，使刀具具有更好的减摩性能；与滑移区微织构参数相比，粘结区微织构参数影响刀具铣削性能更加显著；刀具的主要磨损区域由后刀面过渡到前刀面时的临界切深域为[0.21mm，0.23mm]；以刀具铣削性能和表面质量为评价指标，优化了球头铣刀前刀面介观几何特征参数，优化后的钝圆微织构刀具寿命显著提高，同时刀具失效时磨损面积显著减小，揭示了微织构在刀具整个切削过程中所发挥的积极作用；以铣削力和工件表面完整性作为综合评价指标，优化了球头铣刀后刀面介观几何特征参数，研究发现后刀面介观几何特征可以起到改善工件表面完整性的作用。