Tool wear and hole quality investigation in dry helical milling of Ti-6Al-4V alloy
Tool wear and hole quality investigation in dry helical milling of Ti-6Al-4V alloy
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Ti-6Al-4V 合金干式螺旋铣削刀具磨损和孔质量研究
DOI：
10.1007/s00170-013-5570-0
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发表时间：
2014-03-01
影响因子：
3.4
通讯作者：
Gui, Linjing
中科院分区：
文献类型：
--
作者：
Li, Hao;He, Gaiyun;Gui, Linjing
本文重点研究了Ti-6Al-4V干法螺旋铣削过程中刀具磨损的演变规律及其对钻孔质量的影响。对TiAlN涂层硬质合金刀具进行了实验研究。利用光学显微镜和扫描电子显微镜研究了刀具前缘和周边刃口的磨损特性。试验结果表明，切屑/断裂、扩散和氧化的综合作用对前刀刃失效有显著影响，而后刀面磨损在周边刀刃上占主导地位。切削速度与刀具失效机理密切相关，刀具前缘和周缘磨损率不同，导致在打孔过程中切削力在推力和水平方向上的变化趋势不同。从几何精度、毛刺形成和表面粗糙度三个方面对加工孔的质量进行了评估。加工孔的出口毛刺与前刀刃磨损密切相关。然而，从直径、圆度误差和表面光洁度的角度来看，即使在刀具寿命的近端，也可以观察到高的孔质量，这是由于外围刀具刃口的平滑磨损模式。刀具前缘严重磨损会导致刀具出口毛刺过多，但对钛合金螺旋铣削时的几何形状和表面粗糙度没有明显影响。
This paper focused on combined study on the evolution of tool wear and its influence on borehole quality in dry helical milling of Ti-6Al-4V. The carbide tools with TiAlN coating were used in this experimental investigation. The tool wear characteristics both at front and periphery cutting edges were investigated using an optical microscope and SEM-EDS techniques. The experimental results demonstrate that the combined effects of chipping/fracture, diffusion, and oxidation have significant bearings on front cutting edge failure, while the flank wear was predominant at the periphery cutting edges. The cutting speed was correlated with tool failure mechanizes, and the different wear rates at front and periphery cutting edge caused different variation trends of cutting force in thrust and horizontal direction during hole-making process. The quality of machined holes was evaluated in terms of geometry accuracy, burr formation, and surface roughness. The exit-burrs of machined hole were closely correlated with front cutting edge wear. However, high hole quality was observed even the near end of tool life from the point of view of diameters, roundness error, and surface finish due to the smooth wear pattern at periphery cutting edges. Severe tool wear at front cutting edges will cause excessive exit-burrs, but it has no obvious effect on geometry and surface roughness in helical milling of Ti-6Al-4V.