Ultrasonic welding is a welding type that makes use of ultrasonic vibrations to weld materials. To weld two materials together, they are put under a high level of pressure. The pressure makes the weld strong. Usually, materials that are made of plastic are the ones that are connected together using this method. Aside from plastic, this welding type is also used to weld metals. Whether the materials welded are plastic or metal, the resulting weld is strong, but the bond between metals is definitely stronger.
Ultrasonic vibrations are vital in the success of a weld. Through the vibrations, a welder is able to bond materials without using items like staples, bolts, screws, and nails. Not only is the bond more solid, it is also more clean-looking.
The vibrations have different effects on different materials. On thermoplastics, the areas to be welded are melted by the vibrations. The vibrations bring the melted areas together, creating a solid bond. On metals, the friction caused by ultrasonic vibrations makes the two objects bond together.
Ultrasonic vibrations are produced by a horn called sonotrode. It is a part of the ultrasonic welding machine. The sonotrode is the part of the machine that gets in contact with the materials to be welded. This horn softens thermoplastics and heats up metals. Although vibrations caused by a sonotrode heat up metals, the temperature is not high enough to melt the metals objects. The weld is actually called a cold weld.
The use of ultrasonic welding is common in the production of large quantities of products. This type of welding produces strong and clean welds at a small amount of time. Industries that always need to produce large amounts of their products, such as the medical and automotive industries, use ultrasonic welding in order to meet the demand.
To weld through ultrasonic welding, there are items that are needed. There must be an ultrasonic stack that has a sonotrode and a transducer. There should also be a generator that can supply the power that the transducer needs in order to create ultrasonic vibrations. A controller must be present so the direction that the sonotrode moves can be controlled. There has to be an anvil which is where the materials to be welded are placed. Lastly, there should be two materials that can be welded using ultrasonic energy.
As mentioned previously, plastic and metal are materials that can be welded using ultrasonic welding. With the success of using this welding type in bonding the said materials, studies are being done to know if it could also be used to weld other material types. There is a need for a fast and efficient way to make lots of other products that is why studies are done to know if ultrasonic welding can meet that need. It is only a matter of time before a way to bond other types of materials using ultrasonic energy is developed.