Preparation and Characterization of Ultra-Thin Dicing Blades With Different Bonding Properties

Ultra-thin dicing blade is usually used to achieve a high precision cutting in semiconductor back-end packaging and assembly. Lots of interactional parameters involving in dicing blade preparation and cutting process bring difficulties to high cutting qualities and good working life of dicing blade. In order to address these problems, this study prepared three kinds of dicing blades and characterized the cutting properties of three dicing blades. It first proposed the abrasive exposure coefficient and tool deviation coefficient to provide parameters for the cutting force model. Then the experimental apparatus was set up to verify the proposed cutting force model. And a series of parameters including feed rate, spindle current, edge chipping coefficient, tool wear amount and grinding performance are used to characterize the comprehensive performance of prepared dicing blades. Finally, the edge morphology was observed under 3D microscope to analysis the hardness of different dicing blades. The theoretical and experimental results indicate that the proposed cutting force model can reflect actual cutting process. There is an inverse proportional function between the shedding of abrasive particles and the hardness of the matrix. The cutting performance of dicing blades is very dependent on the material of workpiece. C-dicing blades presents outstanding comprehensive effects with small chips and good self-sharpening properties.

Cutting force prediction considering force-deflection coupling in five-axis milling with fillet-end cutter

With the increasing demand for higher quality and performance of equipment and assembly in aerospace, shipbuilding, medical and other fields, the machining accuracy of parts is facing higher requirements. It is particularly important to predict the cutting force accurately, which is the main physical quantity in the machining process and basis of process inspection and quality control. In this paper, the cutting force model in five-axis milling with fillet-end cutter is proposed, which reveals the law of force-deflection coupling. Firstly, the initial cutter deflection model induced by the ideal cutting force ignoring the effect of deflection is built based on analysis of the geometric characteristics of fillet-end cutter. Then the undeformed chip thickness model is educed considering the cutter posture and cutter deflection. Further, the iterative method is utilized to resolve the coupling relationship between cutter deflection and cutting force. Finally, the cutting force model under force-deflection coupling is established for achieving more accurate prediction. To verify the effectiveness of the proposed cutting force model, the milling experiment is carried out on a five-axis milling center. The measured cutting force values are utilized to inspect the accuracy of prediction models considering and not considering force-deflection coupling respectively. The results show that the proposed method could improve the prediction accuracy of cutting force, which show the effectiveness of taking force-deflection coupling law into consideration clearly. The influence of cutter posture on cutting force is analyzed using the proposed cutting force model. The cutting force decreases with the increasing of lead angle or tilt angle, and the influence of tilt angle is greater than that of lead angle under experimental conditions of five-axis milling using the set process parameters.

Identification of eccentricity for disc milling cutter of indexable two sided inserts

Tool eccentricity has a significant impact on machining quality, accuracy, and operation status of machine tool. It is difficult to accurately identify tool eccentricity. In this paper, the mathematical models of instantaneous undeformed cutting thickness and cutting force considering tool eccentricity are determined by theoretical method. Based on the model, the identification method for eccentricity parameters is proposed, and the eccentricity parameters of disc milling cutter is identified. According to the identified parameters, the cutting force is verified. The results show that most of the values of measured cutting forces are greater than the predicted ones considering tool eccentricity. In the future, it is necessary to establish a new cutting force model considering both tool eccentricity and tool wear.

Experimental investigations of chatter and critical cutting conditions in turning

Vibration can cause problems when it occurs during machining, especially if it cannot be damped and continuous to increase, a phenomenon known as chatter. This thesis project focuses on reviewing the state-of-the-arts work in chatter research, identifying a reliable mechanistic dynamic cutting force model for orthogonal cutting operations when machining slender shafts, carrying out a series of experiments on uniform and stepped workpiece[s], and validating the theoretical predictions of chatter onset conditions against experimental results.

Experimental investigations of chatter and critical cutting conditions in turning

Vibration can cause problems when it occurs during machining, especially if it cannot be damped and continuous to increase, a phenomenon known as chatter. This thesis project focuses on reviewing the state-of-the-arts work in chatter research, identifying a reliable mechanistic dynamic cutting force model for orthogonal cutting operations when machining slender shafts, carrying out a series of experiments on uniform and stepped workpiece[s], and validating the theoretical predictions of chatter onset conditions against experimental results.