硬质合金刀具几何角度对高速铣削钛合金TC4切屑形态的影响

Study on effect of geometrical angle of cemented carbide tool on chip formation in high speed milling titanium alloy TC4

为探讨高速铣削中刀具的几何角度对切屑形态的影响,采用不同的几何角度,进行钛合金TC4的高速铣削,以获得更好的加工表面质量。采用Advant Edge有限元分析软件,建立高速铣削钛合金TC4的有限元模型,在给定的切削条件下,针对不同的刀具前角和螺旋角,对钛合金TC4切削过程中的切屑形态进行仿真,分析刀具角度与切屑温度及形态的关系。并以相同的刀具几何角度和铣削参数进行了加工实验。结果表明:高速铣削条件下,切屑的温度高于工件和刀具的温度,切削热通过切屑散发,有利于切削;适当增加前角,切屑形态规则且均匀,表面质量较好。螺旋角在一定范围内增大,使切屑形态不规则,对加工产生不利影响。模拟与铣削实验的切屑形态具有相似性,可以为后续分析切屑的形态及形成过程提供依据。

This paper is focused on an investigation into the influence of the geometrical angle of the tool in the high speed milling on the chip morphology. The investigation is achieved by performing the high speed milling of the titanium alloy TC4 using the combination of simulation and experiment and using the different geometrical angle of the cemented carbide tool ; and examining the chip morphology to obtain better processing surface quality. The investigation also involves developing the finite element model of high speed milling titanium alloy TC4 using the AdvantEdge finite element analysis software; given the cutting conditions, simulating the chip formation of titanium alloy TC4 for different relief angle and helix angle of the tool and thereby analyzing the relationship among the tool angle, milling temperature, and chip morphology; and ultimately performing machining experiment using the same tool geometric angle and milling parameters. The results demonstrate that, given the condition of high speed milling, the chip has a higher temperature than the workpiece and the cutting tool and enables the cutting heat dissipation, aiding cutting process; an appropriate increase in the rake angle gives a regular and uniform chip formation and a better surface quality; an increase in the helix angle in a certain range tends to leave the chip shape irregular, adversely affecting the process; and there occurs a similarity between the chip formation gained from the simulation and that of the milling experiment. The study may provide a basis for the analysis of the chip formation and forming process.