钎焊金刚石套料钻CFRP制孔研究

Analysis on CFRP Hole Making with Brazed Diamond Core Drill

碳纤维增强复合材料(Carbon fiber reinforced plastics,CFRP)中高硬度碳纤维易加速孔加工钻头的磨损,导致加工质量变差。采用钎焊金刚石套料钻加工CFRP不仅可提高钻头的耐磨性,加工质量也得到了改善。为更好地优化提高套料钻加工性能,试验采用有序排布的金刚石磨粒制作钎焊套料钻,尝试通过改变磨粒数量来调整单颗磨粒切厚大小,对相同工艺参数下不同单颗磨粒切厚对钻削轴向力、孔壁粗糙度以及出入口质量的影响进行了研究。建立了金刚石磨粒的运动模型,并分析了套料钻制孔中已加工表面的形成过程。试验结果与分析表明:制孔质量与容屑空间和单颗磨粒切厚有关。在容屑空间充足的情况下,随着单颗磨粒切厚的减小,轴向力减小,制孔质量提高。

The high hardness of carbon fiber in carbon fiber reinforced plastics （CFRP） leads to quick wear, low durability of drills, and poor machining quality in drilling process. Appling brazed diamond core drill to drilling CFRP can improve drill durability and increase machining quality. In order to optimize the setting of diamond grits on core drill, the diamond grits are orderly set to make core drill, and the maximum undeformed chip thickness are changed through changing the diamond quantity. The influences of maximum undeformed chip thickness on thrust force, surface roughness of hole wall and quality of hole entrance and exit are compared under the same machining parameters. The moving model of diamond grits is set up to analyze the forming process of machined surface. The results and analysis show that the drilling quality is influenced by chip storage space and the maximum undeformed chip thickness. If the chip storage space is sufficient, the thrust force decreases and the drilling quality improves with the decreasing maximum undeformed chip thickness.