This paper discusses the use of vibration drilling method for hole making in composite materials. The special feature of advanced composite materials is the difficulty of machining by conventional methods. The occurrence of defects such as matrix cracking, delamination and fibers failure, thermal degradation of matrix obtained in the process of making holes requires the development of new technological solutions and special equipment and tooling. As an alternative, along with cutting and abrasive machining methods for composite materials, we can consider vibration drilling, laser, ultrasonic and abrasive blasting machining of holes. The Department of Engineering Technologies and Equipment of Southwest State University has made a device intended for vibration drilling of holes in composite materials. Using the proposed method allows us to reduce the vibrations along the drill axis, both in the low-frequency and high-frequency range (20 to 500 Hz). It also allows us to change the frequency of vibration without stopping the cutting process. The device is designed for metall cutting machines related to drilling-and-boring group of machines with a vertical spindle to increase performance and improve the quality of holes shaping. Technical specifications of the designed device provide the set tool advances, the required frequency of spindle rotation, giving the necessary cutting speed (they depend on technical features of the selected machine), as well as the necessary amplitude and high frequency axial oscillations of the tool. To convert electric oscillations into mechanical ones there has been adopted the scheme of two inductance coils, being placed one above the other. The proposed method of electro-impulse drilling will solve the problem of processing composite materials (matrix cracking, delamination and fiber failures) and improve the quality and productivity of making holes in composite materials.

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The article presents a study on the influence of changes in the angle of rotation of the tool axis produced relative to the involute profile on the accuracy of its approximation of the hyperboloid tool and also the effect on the accuracy of the generating line segmentation.

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