摘要：针对AISI 4340合金结构钢难加工的特点，选用PVD硬质合金涂层刀具进行高速干铣削试验，选用扫描电子显微镜（SEM）观察失效刀具表面的磨损形貌特征，选用能谱分析仪（EDS）分析磨损刀具表面的元素分布及含量，揭示刀具的磨损机理。研究结果表明：刀具寿命与切削参数选取有关，随着切削速度的增加，刀具磨损加快，刀具寿命降低。硬质合金涂层刀具的主要磨损形式是前刀面磨损和后刀面磨损，前刀面磨损机理主要是粘结磨损、涂层剥落、切削刃微崩刃；后刀面磨损机理主要是磨粒磨损、粘结磨损、扩散磨损、微裂纹。

关键词：高速铣削；涂层刀具；磨损机理；AISI 4340钢

中图分类号：TG501；TH161文献标志码：A

Wear Mechanisms of Coated Tool in High Speed

Milling of AISI 4340 Alloy Constructional Steel

Yu Yingzhao，Gao Jun，Zheng Guangming，Zhao Guoyong，Chu Manfu

Abstract:According to difficult to machining of AISI 4340 alloy constructural steel.A series of experiments are conducted in high speed dry milling of AISI 4340 with PVD carbide coated tool.Wear morphology of the failure tool is observed by SEM，and element distribution and content of the worm surface is analyzed by EDS.The results show that the tool life is related to the selection of cutting parameters，which the cutting speed is improved lead to the tool wear was accelerated and the tool life is reduced.The main wear forms of the carbide coated tool are the rake wear and the flank wear.The dominant wear mechanisms of the rake face were adhesive wear，coating flaking，meanwhile with microchipping on cutting edge.The main wear mechanisms of flank face are abrasive wear，adhesive wear，diffusion wear and microcrack.

Keywords:high speed milling；coated tool；wear mechanisms；AISI 4340 steel