Ultrasonic welding is one of the most common techniques for joining thermoplastic subassemblies. Its primary advantages are its short cycle times and moderate capital costs. Typical manual cycle times are less than three to five seconds, resulting in production rates above 500 units per hour. Ultrasonic Welding Amplitude is the peak-to-peak vertical motion at the horn face. It has the most impact on the ultrasonic process, in that the heat generated at the joint interface is based on the square of the amplitude. Therefore, small increases or decreases in amplitude have a greater affect than changes to other parameters, because the results are magnified by the square rather than incrementally. During the ultrasonic welding process, mechanical vibrations with defined amplitude, force and duration are applied to the materials to be welded. Due to intermolecular and surface friction heat is generated and melts the material. The core of the ultrasonic welding system is the ultrasonic vibration group called ultrasonic stack. In the ultrasonic stack, there are the piezoelectric converter, the booster (amplitude transformer) and the sonotrode. The ultrasonic vibration group creates and expands with the ultrasonic frequency. The resulting vibrations are longitudinal, vertical waves. The travel of the weld tool, meaning the distance between the peak position and the zero position, is referred to as amplitude - in ultrasonic welding the amplitude is between 20 μm and 130 μm. Ultrasonic welding amplitude by using static gain factors of the components that make up an acoustic stack: the converter, booster, and horn. (Gain is the ratio of output amplitude to input amplitude of a horn or booster. To arrive at approximate stack amplitude, multiply the amplitude of the converter by the gain factors of the booster and horn. Output Amplitude = Converter Amplitude X Booster Gain X Horn Gain Depending on the material and ultrasonic process utilized, different amplitudes will be necessary. Amplitude can be measured in either thousandths of microns.

1. www.sonicwelding.net / www.ultrasonicwelding.eu by Sonikel Ultrasonics
ULTRASONIC WELDING AMPLITUDE
Ultrasonic welding is one of the most common techniques for joining thermoplastic
subassemblies. Its primary advantages are its short cycle times and moderate capital
costs. Typical manual cycle times are less than three to five seconds, resulting in
production rates above 500 units per hour.
Ultrasonic Welding Amplitude is the peak-to-peak vertical motion at the horn face. It
has the most impact on the ultrasonic process, in that the heat generated at the joint
interface is based on the square of the amplitude. Therefore, small increases or
decreases in amplitude have a greater affect than changes to other parameters,
because the results are magnified by the square rather than incrementally.
During the ultrasonic welding process, mechanical vibrations with defined amplitude,
force and duration are applied to the materials to be welded. Due to intermolecular
and surface friction heat is generated and melts the material. The core of the
ultrasonic welding system is the ultrasonic vibration group called ultrasonic stack. In
the ultrasonic stack, there are the piezoelectric converter, the booster (amplitude
transformer) and the sonotrode. The ultrasonic vibration group creates and expands
with the ultrasonic frequency. The resulting vibrations are longitudinal, vertical waves.
The travel of the weld tool, meaning the distance between the peak position and the
zero position, is referred to as amplitude - in ultrasonic welding the amplitude is
between 20 μm and 130 μm.
Ultrasonic welding amplitude by using static gain factors of the components that
make up an acoustic stack: the converter, booster, and horn. (Gain is the ratio of
output amplitude to input amplitude of a horn or booster. To arrive at approximate
stack amplitude, multiply the amplitude of the converter by the gain factors of the
booster and horn.
Output Amplitude = Converter Amplitude X Booster Gain X Horn Gain
Depending on the material and ultrasonic process utilized, different amplitudes will be
necessary. Amplitude can be measured in either thousandths of microns.

2. www.sonicwelding.net / www.ultrasonicwelding.eu by Sonikel Ultrasonics
Amorphous
Materials
Amplitude Level at 20 kHz
(um)
Acrylonitrile Butadiene Styrene (ABS) 30-70
Acrylonitrile Styrene Acrylate (ASA) 30-70
Polycarbonate (PC) 40-80
PC/ABS 60-100
Polycarbonate/Polyester 50-100
Polyetherimide (PEI) 70-100
Polyethersulfone (PES) 70-100
Polymethyl Methacrylate (Acrylic, PMMA) 40-70
Polyphenylene Oxide (PPO) 50-90
Polystyrene (PS) 30-70
Polysulfone (PSU) 70-100
Polyvinyl Chloride (rigid PVC) 40-80
Styrene-Acrylonitrile (SAN) 30-70
Semi-Crystalline
Materials
Amplitude Level at 20 kHz
(um)
Cellulosics (CA, CAB, CAP) 60-100
Liquid Crystal Polymer (LCP) 70-120
Copolyester 70-120
Polyoxymethylene, Polyacetal (POM) 70-120
Polyamid (Nylon, PA) 70-120
Polybutylene Terephthalate (Polyester, PBT) 70-120
Polyethylene Terephthalate (Polyester, PET) 80-120
Polyetheretherketone (PEEK) 70-120
Polyethylene (PE) 90-120
Polyphenylene Sulfide (PPS) 80-120
Polypropylene (PP) 90-120
Sonikel Ultrasonics, has ISO 9001:2008 and ISO 10002 System Certificates. Sonikel
products have CE Certification with all LVD test reports.
For further information, you can visit the following web sites;
www.sonicwelding.net
www.ultrasonicwelding.eu