Q: Can different materials be welded?
A: According to experience, to achieve true chemical molecular bonding, it must be the same material welding. There are exceptions, however, where the material properties are close enough to ensure adequate fusion during welding. For example, ABS can be welded to PMMA or PC with excellent results. Although a few combinations of other materials have varying degrees of compatibility, welding of different materials should be avoided in design. If ultrasonic riveting is used, material compatibility is not a concern. For example, with rivet points formed by riveting (mushroom heads), you can attach a metal plate to a plastic shell. For the film and filter film welding to the plastic surface, it is through the melting of plastic into the film multi-space structure, forming a mechanical connection. It's like a piece of gum stuck to a carpet, mechanically bonded, not chemically bonded.

Q: Does the shape of the product affect the welding? Round or sharp corners for joint turning?
A: Square and round parts can be welded successfully, but each has its own unique challenges. For square parts that need to be sealed, sharp 90 degree direction changes should be avoided when the joint turns. Materials tend to flow accidentally in these areas and can cause leaks. Therefore, we recommend rounded corners for turning. This also applies to the internal structure of parts and reinforcement design. Sharp 90-degree internal angles tend to cause stress concentration and accumulation under vibration load, resulting in damage, so it is necessary to increase the radius of fillet.

Q: What is the difference between far field welding and near field welding?

A: Far-field welding refers to the distance between the welding head and the contact surface of the part and the joint, so the vibration energy must travel A longer distance to reach the joint. Although there are many successful far field applications, near field welding is preferred. Especially when soft semi-crystalline thermoplastics are used, far field welding will lose a lot of vibration energy.