车削Ti_2AlNb金属间化合物刀片磨损形态及原因分析

Tool Wear Characteristic Analysis of Turning Experiments on Ti_2AlNb Intermetallic Compound Material

采用不同刀尖圆弧半径的涂层硬质合金刀片对Ti_2AlNb金属间化合物材料进行车削试验研究,用扫描电子显微镜SEM观察刀片磨损形貌,通过能量分散光谱EDS分析刀片表面的元素分布及含量,并对刀片磨损形态和失效原因进行分析。研究结果表明:切削Ti_2AlNb过程中,涂层硬质合金刀片磨损形态为前刀面磨损、后刀面磨损、沟槽磨损和崩刃以及涂层剥落等;增大刀尖圆角有利于提高刀片寿命,并且小刀尖半径硬质合金刀片以沟槽磨损为主,大刀尖半径硬质合金刀片以后刀面磨损为主;沟槽磨损主要原因是粘结磨损、氧化磨损、扩散磨损以及疲劳破坏;沟槽磨损初期以粘结磨损、氧化磨损为主,中后期以扩散磨损以及疲劳破坏为主;后刀面磨损主要原因是磨粒磨损和粘结磨损。

In this paper,the conventional cooling turning experiments on Ti2AlNb intermetallic compound material by using coated carbide tools of different corner radius are presented. The worn surface morphology and failure causes of different tools with same cutting parameters are studied by scaning electronic microscope（ SEM） and energy disperse spectrum（ EDS）. The results show that the wear morphology of the coated carbide tools of different corner radius are both rake face wear,flank wear,groove wear and tool coating peeling and chipping. The increases of corner radius are beneficial to improve tool life. The main wear mode of coated carbide tool with small corner radius is groove wear and the main wear mode of coated carbide tool with large corner radius is flank wear. The main causes of groove wear are bonding wear,oxidation wear,diffusion wear and fatigue failure. In the early stage of groove wear,the bonding wear and oxidation wear are the main factors,diffusion wear and fatigue failure are the mainly factors of middle and later wear. The main causes of flank wear are abrasive wear and adhesive wear.