Numerical Evaluation of State of the Art Horn Designs for Rotary Ultrasonic Vibration Assisted Machining of Nomex Honeycomb Composite

Ultrasonic horn plays vital role in achieving vibration amplitude suitable for efficient machining of advanced composites. Due to very high operating frequency of at least of ultrasonic machining system, horn may be subjected to high stresses leading to failure. Mechanical horn is designed to get optimum vibration amplification while keeping stresses in acceptable limits. In this research, state of the art ultrasonic horns were designed with same length and diameters at the transducer side and tool ends under similar operating conditions. All standard and hybrid ultrasonic horns, including some new designs, suitable for machining applications were evaluated through finite element analysis. Modal analysis was performed for computing axial modal frequencies, whereas harmonic analysis was carried out to determine vibration amplitude, stresses and factor of safety. The performance of state of the art ultrasonic horn designs were later compared in terms of vibration amplification, stresses and operating life. The axial modal frequency and amplitude of vibration achieved by barrel, cylindrical-double conical and hollow exponential horns were observed to be greater as compared to the step horn, however the former were prone to greater stress concentrations and low operating life. Reasonably higher vibration amplification, factor of safety and low stresses were achieved by Bezier, cylindrical-catenoidal, cylindrical-Bezier, step-conical, step-catenoidal, step-Bezier, double conical, multistep and multistep-conical horn designs. Remarkably, circular hollow exponential and multistep-conical ultrasonic horns were observed to achieve vibration amplification, factor of safety and operating life higher than that of commercially available step horn.

Design of Ultrasonic Conical Horn using Aluminium Alloy and Steel

Horn plays an important role in ultrasonic machining process. The design of horn is critical to its efficiency and quality of machining process. Ultrasonic horns are tuned. Components designed to vibrate in a longitudinal mode at ultrasonic. Frequencies. Reliable performance of such horns is normally decided by the uniformity of vibration amplitude at the working surface and the stress developed during loading condition. The design parameters of horn are calculated from the theoretical derivation of horn. By these parameters, the horn is designed and analyzed using CREO PRO and ANSYS software. In this paper the main object of the project is to Improve the performance of the Horn from the analysis test results, The horn is compared with other available horn results by comparing its natural frequency, amplitude vibration and temperature of the horn.

Design and Analysis of Slotted Horn for Ultrasonic Plastic Welding

Ultrasonic horns are tuned components designed to vibrate in a longitudinal mode at ultrasonic frequencies. Reliable performance of such horns is normally associated with the amplitude of vibration, uniformity of vibration amplitude at the working surface and the avoidance of modal participation by non-tuned modes at the operating frequency. In order to maximise vibration amplitude uniformity, standard slotting configurations are included in the horn design. In this work the slot position in the horn is optimised using factorial design of experiments and the mathematical model developed is further interfaced with genetic algorithm. Modal and harmonic analysis of the horn is done using ANSYS software package. It is observed that slotted block horn with optimised slot position vibrates in longitudinal mode with uniform displacement amplitude across the face of the sonotrode.