Abstract

In this study, the effect of drilling quality on fatigue life of UD, 0/90, and ± 45 fiber angle carbon fiber reinforced plastics (CFRP) was investigated. CFRPs were drilled using WC, HSS, and Brad Spur tool types that have different geometries and materials at different feed rates of 0.05, 0.10, and 0.15 mm/rev, and at the different spindle speeds of 1000, 3000 and 5000 rev/min. Thrust forces were measured during the drilling of CFRPs, and surface roughnesses, deformation factors, and maximum tensile forces were measured after drilling operations. Thrust force, surface roughness, and deformation factor were evaluated in terms of drilling quality. The drilling parameters that cause the best, average, and worst drilling quality were determined. Then, fatigue behaviors of CFRPs drilled in these drilling parameters were investigated. Fatigue tests were carried out at %75, %80, %85, and %90 load ratios based on the lowest tensile force of the drilled samples. As a result of the study, it was determined that the thrust force, the deformation factor, and the surface roughness increased as the feed rate increased. However, the thrust force, the deformation factor, and the surface roughness decreased as the spindle speed increased. Besides, the best drilling quality was obtained from the drilling operation performed using WC tool type, at a spindle speed of 5000 rev/min and a feed rate of 0.05 mm/rev. The worst drilling quality was obtained from the drilling operation performed using Brad Spur tool type, at a spindle speed of 1000 rev/min and a feed rate of 0.15 mm/rev. With the decreasing drilling quality, a significant decrease occurred in the tensile force and fatigue life of CFRPs. The tensile load and fatigue life of CFRPs drilled in optimum drilling parameters were obtained higher. In the case of selecting the correct drilling parameters, it was observed that the reduction in fatigue life of CFRPs could be prevented ratios of %22–49.

Graphical abstract

中文翻译：

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孔质量对不同层取向角的CFRP疲劳寿命的影响

摘要

在这项研究中，研究了钻孔质量对UD，0/90和±45纤维角碳纤维增强塑料（CFRP）的疲劳寿命的影响。使用WC，HSS和Brad Spur工具类型进行CFRP钻孔，这些工具具有不同的几何形状和材料，且进给速度分别为0.05、0.10和0.15 mm / rev，主轴转速分别为1000、3000和5000 rev / min。在CFRP钻孔过程中测量了推力，在钻孔后测量了表面粗糙度，变形系数和最大拉力。根据钻探质量评估了推力，表面粗糙度和变形系数。确定了导致最佳，平均和最差钻孔质量的钻孔参数。然后，研究了在这些钻孔参数下钻孔的CFRP的疲劳行为。基于所钻样品的最低拉力，在％75，％80，％85和％90的载荷比下进行了疲劳测试。研究结果表明，推力，变形系数和表面粗糙度随着进给速度的增加而增加。但是，随着主轴转速的增加，推力，变形系数和表面粗糙度降低。此外，从使用WC工具类型进行的钻孔操作中获得最佳钻孔质量，主轴转速为5000转/分钟，进给速度为0.05毫米/转。从使用Brad Spur工具类型进行的钻孔操作中获得的钻孔质量最差，主轴转速为1000转/分钟，进给速度为0.15毫米/转。随着钻井质量的下降，CFRP的拉伸力和疲劳寿命显着降低。获得了在最佳钻孔参数下钻孔的CFRP的拉伸载荷和疲劳寿命。在选择正确的钻孔参数的情况下，可以观察到CFRP疲劳寿命的降低可以防止的比率为22％至49％。

图形概要