Factors affecting ultrasonic welding
The basic principle of ultrasonic assembly involves the conversion of high frequency electrical energy into high frequency mechanical energy in the form of reciprocating vertical motion, which, when applied to thermoplastics, produces frictional heat at the plastic/plastic or plastic/metal interface.
In ultrasonic welding, this frictional heat melts the plastic, thereby merging the two surfaces together. During ultrasonic piles, forming or inserting, the controlled flow of molten plastic is used to capture or retain another component in place (pile/form) or package metal insert (insert).
To accomplish this assembly, ultrasonic welding systems of various configurations, power levels and frequencies can be used. There are bench presses, hand-held welders, stepper or servo motor driven systems, hot melt and inserters, and ultrasonic kits and stack assemblies for OEM system integrators.
There are many factors that influence successful ultrasonic welding: tools, materials, frequency, joint design, and welding parameters.