Laser welding is a welding method using a high energy density laser beam as a heat source, i.e., the laser radiation heats the surface of the workpiece, and the heat from the surface spreads internally through heat conduction, causing the workpiece to melt and form a specific molten pool. As shown in Fig. 1, the laser beam passes through the upper light-transmitting material and is then absorbed by the lower material, where the laser energy is absorbed and converted into heat energy, due to the fact that the two layers are pressed together. The thermal energy is conducted from the absorbing layer to the light-transmitting layer, causing the two layers to melt and combine.
It can be seen that the energy of the laser beam must be absorbed by the plastic to achieve good welding results, so plastic laser welding is generally used CO2 laser. In addition, not all plastics can be welded with laser welding. Plastic can be distinguished as thermosetting and thermoplastic two categories. One of the thermosetting plastic does not have repeated molding, can not be welded, and thermoplastic plastic will melt after reheating (can be used to heat and cooling, so that it produces reversible changes), is the so-called physical changes, and therefore has a weldability.
Laser welding is characterized by high speed and good results compared to other welding methods, and the resulting mechanical and thermal stresses are small, so it is particularly suitable for electronic components such as mice, cell phones, connecting devices and other precision processing, as well as for complex parts that need to be fused in a cleaner way, such as plastic products containing circuit boards. Industries such as automotive, medical, consumer electronics, food, etc. are ideal application areas for laser welding.
Automotive
Plastic laser welding machines are used in a wide range of applications in the automotive industry, such as automatic door locks, engine sensors, cab racks, fuel nozzles, gearshift racks, etc. There are already some models that use laser welding for their taillights as well, such as HYUNDAI's top-of-the-line flagship models, the GENESIS and Equus.
Medical field
Plastic laser welding machines can be used to manufacture liquid reservoirs, liquid filter materials, hose connectors, ostomy bags, hearing aids, implants, microfluidic devices for analysis and so on.
Packaging industry
For example, the packaging of high-level industrial products, plastic film welding technology, you can get high-speed processing, reliable seams, beautiful appearance of the plastic packaging. Laser welding connection of plastic material outer packaging material. Plastic materials are thermoplastics and artificial rubber.
Laser welding of plastics has a low cost, non-polluting, high speed, easy processing, easy to achieve precision numerical control, raw materials for a wide range of applications, jointing and good workmanship and other comprehensive advantages, with the plastic welding process research and plastic laser welding equipment gradually commercialized, plastic laser welding applications will certainly become more and more widespread, more and more mature technology.
