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The Langevin transducer is commonly used to generate vibration waves, based on the piezoelectric effect, for variety of essential industrial applications such as welding and machining. Researchers are still investigating the different design aspects of Langevin transducer in order to improve the performance of vibration generation system. Furthermore, measuring the output amplitude of the Langevin transducer is a key feature because vibration amplitude plays a vital role in the performance of any vibration-assisted applications. However, it is a sophisticated process which requires high-cost equipment. The aim of this work is to develop an electromechanical system used to measure and to control the ultrasonic Langevin transducer output amplitude. Thus, a detailed design procedure of Langevin transducer was preformed including the investigation of different horn profiles. Firstly, the transducer's model features were established based on the wave equation as a start point for the finite element (FE) model. Subsequently, different ultrasonic horn geometries were investigated through the FE model. Secondly and based on the FE results, the stepped horn was selected for fabrication and experimental validation. The FE and experimental results showed a good agreement with a deviation of 8%. Finally, an electromechanical system has been developed to measure the transducer amplitude at different resonance frequencies. The transducer showed more stability and produced higher amplitude at frequencies of 33.33 and 43.54 kHz. [ABSTRACT FROM AUTHOR]

Modelling the thrust force of rotary ultrasonic drilling (RUD) is an important aspect for optimizing the process parameters and predicting the material cracking and edge chipping. Mainly, the material removal of brittle material occurs mainly through the brittle mode, while the ductile mode occurs in case of micro or nano-depth of cut. This paper introduces a mathematical model for thrust force based on the two material removal modes. The mathematical model correlates the thrust force with the material characteristics and the machining parameters as feed rate, spindle speed, ultrasonic amplitude, frequency and tool abrasive size, tip angle, and concentration. Complete hole drilling and scratch-drilling with depth of 10-μm experiments are conducted in soda glass to verify the model. Thrust force measurement and microstructure features are used to verify the model. The predicted model results agree with the experimental results. The model predicts that the range of feed rate and spindle speed produce the ductile mode cutting. [ABSTRACT FROM AUTHOR]

Ultrasonic-assisted drilling (UAD) is a promising technology used for machining difficult-to-cut materials. In this paper, experimental investigations were conducted to study the drilling forces and edge chipping for soda glass using diamond abrasive tools. Cutting fluid was used at different levels of feed rate, spindle speed, and tool concentrations. The thrust force, torque, and edge chipping parameters (width, depth, and angle) at entrance and exit sides of the drilled holes were evaluated. Statistical analysis was carried out to support the experimental findings, optimize the process responses, and construct the mean effect plots and interactions of the process parameters. The results show that the thrust force increases when using normal tool concentration, lower spindle speeds, and higher feed rates. The normal concentration, low spindle speed, and high feed rate decrease the exit chipping width. The theoretical analysis proves that the chipping force is less than the impact force and they are not correlated. [ABSTRACT FROM AUTHOR]