碳纤维/树脂基复合材料高速铣削的刀具磨损机理

采用涂层(Ti CN,Ti Al N)与无涂层超细晶粒硬质合金立铣刀对碳纤维/树脂基复合材料进行高速铣削试验,研究了刀具后刀面磨损带扩展及刀具磨损规律,并探讨了切削力、毛刺随着刀具磨损的变化趋势,观察了刀具的微观磨损形貌,分析了刀具的磨损机理。结果表明:在相同的切削条件下,无涂层刀具的后刀面磨损量及切削力最大,毛刺扩展严重,后刀面主要发生磨粒磨损,由于黏着磨损和氧化磨损对切削刃的弱化作用,主切削刃发生了微崩刃;Ti CN涂层刀具后刀面主要发生磨粒磨损,并伴随有黏着磨损和轻微的氧化磨损,失效形式为剥落和微崩刃;Ti Al N涂层刀具的后刀面磨损量及切削力最小,毛刺扩展缓慢,更适合碳纤维复合材料的加工。其后刀面主要发生了磨粒磨损,其失效形式为剥落。

Wear Mechanism of Tool in High-speed Milling of Carbon/Epoxy Composite

The coated (TiCN, TiAlN) and uncoated carbide end mills of ultra-fine grain were adopted for high-speed milling of carbon/epoxy composite. First, the expansion and the law of tool flank wear were investigated. Then, the variation of cutting force and burrs with the trend of tool wear were analyzed. The microscopic morphology of the tool wear was observed and the wear mechanism of the tool was analyzed. The results show that: the uncoated tool obtains the largest flank wear and cutting force, and the expansion of burr is severer than the other two under the same cutting conditions. The flank face mainly suffers abrasive wear. Micro-chipping is observed to be the tool failure ascribed to the negative effects of adhesive wear and oxidation wear on the main cutting edge. TiCN coated tools mainly suffers abrasive wear, accompanied adhesive wear and slight oxidation wear, while the form of failure is flaking and micro-chipping. TiAlN coated tools obtaining the smallest flank wear, cutting force and burrs expansion, are more suitable for processing carbon fiber composites. The flank face mainly suffers abrasive wear while the main failure is flaking.