Ultrasonic welding technology, is a relatively new plastics welding assembly technology,
1.The sonic line cross section design, and the welding part of total volume, relative to the entire product volume ratio.
2.The ultrasonic welding on supersonic machine transfer machine technology, and ultrasound operator careful degree have great dependence.
Ultrasonic welding technology
Welding:
Referring to the generalized two products of thermoplastic welding process.When sonic to stop vibration,
The solid material is melted, the completed weld.The joint strength is close to a one-piece intergrowth material,
As long as the product of the joint surface is designed to match,
Completely sealed is absolutely no problem,
Dish in:
Melting mechanical lock is formed of a different material plastic bolt process.
Embedded:
A metallic element is embedded in the plastic products reserved hole.
With high intensity, short molding cycle rapid installation advantages!!
Similar to the design of die insert!
Bent / generation
Sonic the fitting part melting and consisting of a plastic protruding parts or plastic pipe or other extrusion parts.The advantage of this approach is that processing of fast, low pressure, good appearance and the material nature to overcome.
Point welding:
Spot welding is not reserved or energy control two thermoplastic components of local welding.Spot welding can also generate a strong adhesive structure, is particularly suitable for large parts, a protruding piece of plastic or pouring thermoplastic and those with complex structure, difficult to enter the joint surface of product.
Shear:
Cutting and sealing some order and disorder of the thermoplastic material ultrasonic technology.In this way the seal edge crack, and no burr, curling phenomenon.
Textile / film sealing textile products and some film seal can also be used to the ultrasonic.It can be on the film carries out tight pressing, also on textiles was neat localized shear and seal.Suture at the same time also played a decorative role.
Thermoplastic and thermosetting polymers:
The single body combined together by a process known as "polymerization".The polymer can be divided into two major categories: thermoplastic and thermosetting.Heating a thermoplastic material after molding can once again softening and molding, base experienced just state changes only. This characteristic makes decisions of thermoplastic material by ultrasonic pressure adaptability.Thermosetting material is passed through an irreversible chemical reaction, heat or pressure, again cannot make the Molded Thermosetting products softening, so has traditionally been thought of thermosetting material is not suitable for the use of ultrasound.
Influence factors of ultrasonic welding
Speaking of thermoplastic plastic welding relay, not when it comes to pressure of ultrasound on various resin requirement.The main factors include the polymer structure, melting temperature, flexibility (hardness), chemical structure.
Polymer structure
Non crystallizable polymer disordered molecular arrangement, has the obvious material gradually become soft, melting and flowing temperature (Tg glass transition temperature).This kind of resin is usually effective supersonic vibration transmission and in a quite wide pressure / amplitude range to achieve good welding.
Semi crystalline polymer ordered molecular arrangement, with the apparent melting point (Tm melting temperature) and again solidifying point.Solid state crystalline polymer is flexible, can absorb part of high frequency mechanical vibration.So this kind of polymer is not easy to ultrasonic vibration energy to the pressing surface, help to demand higher amplitude.Very high energy (high melting heat) to semi crystalline structure interrupted so that material from the crystalline state to the flow state, it also determines the type of material's melting point clear, the molten material once leaving the heat source, lower temperature will cause the rapid solidification material.So we must consider the specialty of materials (such as: high amplitude, the junction of good design, and ultrasonic fixture effective contact, and excellent work equipment) in order to obtain the ultrasonic welding success.
Melting temperature
The melting point of the polymer is higher, the required welding ultrasonic energy more.
Hardness (modulus of elasticity)
The hardness of the material on whether it can effective transmission of ultrasonic vibration is very influential.Generally speaking, the more rigid material and its transmission force stronger.