Abstract: A method of welding includes providing first and second joining partners, providing a welding apparatus that includes a sonotrode comprising a structured working surface, arranging the first and second joining partners to contact one another, and forming a welded connection between the first and second joining partners by contacting the first joining partner with the structured working surface and vibrating the sonotrode at an ultrasonic frequency, wherein the structured working surface comprises a plurality of apexes, a plurality of nadirs between immediately adjacent ones of the apexes, and planar sidewalls that extend between the nadirs and the apexes, and wherein for each of the apexes the planar sidewalls on either side of the respective apex extend along first and second planes that intersect one another at an acute angle.

Abstract: An ultrasonic welding apparatus includes a sonotrode comprising a structured working surface that comprises a plurality of apexes, a plurality of nadirs between immediately adjacent ones of the apexes, and planar sidewalls that extend between the nadirs and the apexes, and for each of the apexes the planar sidewalls on either side of the respective apex extend along first and second planes that intersect one another at an acute angle.

Abstract: A method for calibrating a second bonding machine based on a calibrated first bonding machine is disclosed. The first bonding machine includes a first ultrasonic transducer. The second bonding machine includes a second ultrasonic transducer and a power supply. The method includes providing a first electrical calibration supply that causes the first ultrasonic transducer to oscillate at a first calibration amplitude when it is damped by a mechanical damping, providing a second electrical calibration supply that causes the second ultrasonic transducer to oscillate at the same calibration amplitude when it is damped by the same mechanical damping.

Abstract: An ultrasonic welding apparatus includes a sonotrode comprising a structured working surface that comprises a plurality of apexes, a plurality of nadirs between immediately adjacent ones of the apexes, and planar sidewalls that extend between the nadirs and the apexes, and for each of the apexes the planar sidewalls on either side of the respective apex extend along first and second planes that intersect one another at an acute angle.

Abstract: A method for calibrating a second bonding machine based on a calibrated first bonding machine is disclosed. The first bonding machine includes a first ultrasonic transducer. The second bonding machine includes a second ultrasonic transducer and a power supply. The method includes providing a first electrical calibration supply that causes the first ultrasonic transducer to oscillate at a first calibration amplitude when it is damped by a mechanical damping, providing a second electrical calibration supply that causes the second ultrasonic transducer to oscillate at the same calibration amplitude when it is damped by the same mechanical damping.