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Carbon fiber reinforced plastics (CFRPs) are employed in many industrial applications because of their attractive mechanical and structural properties. However, to date, drilling is still considered as the most pivotal process in manufacturing/assembly of CFRPs components, and the delamination damage can be regarded as the most severe machining-induced issue in the drilling process. To solve this problem, a delamination prediction model for CFRPs using Ultrasonic Vibration Assisted Drilling (UVAD) with the abrasive diamond hole saw or core drill is proposed to calculate delamination factor and thickness. The approach of the modeling development starts from simplified for tool and CFRPs workpiece, calculating the total cutting force and the critical thrust force, respectively, and adopting maximum nominal stress criterion to predict delamination. Experimental validation has indicated that the calculated results showed a reasonable agreement with the experimental results on the basis of both delamination factor and thickness, proving the feasibility and the accuracy of the model. This work provides an important reference for selecting and optimizing the drilling parameters to enable delamination-free holes on CFRPs composite. [ABSTRACT FROM AUTHOR]

Textured Abrasive Tool (TAT) offers an effective solution to alleviate thermal issues during machining processes, and laser machining has been identified as one of the most promising fabrication approaches. Laser ablation of TATs has unique process complexity thanks to not only the porous structure of abrasive tools but also the bond-abrasive multiple-material nature. Due to this complexity, most previous investigations on laser-based generation of TATs relied on the single-pass ablation strategy, and therefore most reported TATs had still 2D structures with the same ablation depth. Although the creation of depth-controlled 3D structures based on multiple-pass laser ablation strategy has been investigated in the laser machining community, few attempt applied this technique to TAT fabrication, and this paper aims to fill this gap. Special attentions were paid to the effect of both laser pass numbers and scanning speeds on the ablated structure shapes, depths, widths, and morphologies. The experimental results were well supported by the theoretical explanations, based on which the pragmatic laser parameter selection strategy was proposed. With the strategy, we successfully produced one TAT having 2D sinusoidal profiles and one with 3D staggered hemisphere micro-structures. Grinding trials were performed as well to prove the superior performances of the produced tool. This work might provide important reference for designing and manufacturing the next-generation advanced abrasive tools embedded with complex and functional 3D machining elements. [ABSTRACT FROM AUTHOR]