钛合金铣削过程刀具前刀面磨损解析建模

钛合金Ti6Al4V作为典型的航空航天难加工材料，在其铣削过程中硬质合金刀具的磨损会降低加工过程稳定性，进而影响加工效率和已加工表面表面质量。刀具前刀面磨损会导致刀具刃口强度降低，并影响切屑的流向和折断情况。针对前刀面磨损机理进行分析并构建了月牙洼磨损深度预测模型。首先运用解析方法构建了前刀面应力场模型，得到切屑在前刀面滑动过程中的刀具前刀面应力分布情况及磨损位置。基于刀-屑接触关系的基础上建立了前刀面温度场模型。然后，基于所得刀具前刀面应力与温度分布，构建综合考虑磨粒磨损、粘结磨损与扩散磨损的铣刀月牙洼磨损深度预测模型，获得月牙洼磨损预测曲线；结合铣刀月牙洼磨损带沿切削刃方向分布的特点，建立了随时间变化的铣刀前刀面磨损体积预测模型。最后通过试验验证了切削宽度对前刀面磨损的影响规律，预测结果与试验测量值具有较好的吻合性。结果表明随着切削宽度的增加，月牙洼磨损深度及前刀面磨损体积都随之增加。研究结果为钛合金铣削用刀具的设计和切削参数的合理选择提供了理论基础。

Analytical Modeling of Tool Rake Wear in Titanium Alloy Milling Process

Titanium alloy Ti6Al4V is a typical aerospace difficult-to-machine material. In the milling process, the wear of cemented carbide tools will reduce the stability of the machining process, thereby affecting the machining efficiency and the surface quality of the machined surface. The tool rake face wear will lead to the decrease of tool edge strength, and affect the flow direction and fracture of chip. The wear mechanism of rake face is analyzed and the prediction model of wear depth of crater groove is constructed. Firstly, the stress field model of the rake face is constructed by using the analytical method, and the stress distribution and wear location of the rake face of the milling tool during the sliding of the chip on rake face are obtained. Based on the contact relationship between tool and chip, the temperature field model of rake face is established. Then, based on the stress and temperature distribution on the rake face of the tool, a prediction model of the crater wear depth of the milling tool considering the abrasion wear, adhesion wear and diffusion wear is constructed, and the prediction curve of the crater wear is obtained. Combined with the distribution characteristics of the crater wear zone along the cutting edge direction of the milling tool, the wear volume prediction model of the milling tool rake face with time variation is established. Finally, the influence of cutting width on rake face wear is verified by experiments, and the predicted results are in good agreement with the experimental measurements. The results show that with the increase of cutting width, the wear depth and the wear volume of rake face also increase. The results of this study provide a theoretical basis for the design of milling tools and the reasonable selection of cutting parameters for titanium alloy milling.