Plastic is a kind of high polymer organic compound with good ductility, good processability, high strength, light weight, low cost, energy saving, good corrosion resistance, long service life, etc. It is widely used in food, automobile, aerospace and aviation, medical, 3C, agriculture and other industries. Traditional industry has a variety of welding methods, such as hot plate welding, friction welding, ultrasonic welding, etc. These welding methods played an important role in the development of the plastics industry in the past, but with the continuous improvement of the requirements of industrial manufacturing technology, the production of parts more precise, sensitive, compact, complex shapes, as well as out of the green environmental protection needs, it is difficult for the traditional welding methods to fully meet the needs of the modernization of industry.
The principle of laser welding of plastics:
Two plastics are clamped together under external pressure, the beam generated by the laser is focused on the area to be welded to form a thermal action area, the plastic absorbing laser energy will be converted into thermal energy, the contact surface of the plastic melting, the formation of the melting zone, under the action of the clamping force, the melting area produces intermolecular mixing, cooling to form the weld, the realization of the transmittance of laser welding of plastics.
Advantages of laser welding of plastics:
- No vibration, ultrasonic and other physical hazards, can be used for high-precision component welding
- Non-contact welding, not easy to cause surface damage, deformation
- Non-contact welding, not easy to cause surface damage, deformation do not need to add additional materials, no consumables, low cost
- Fast welding speed, high strength of weld seam, no residue.
- Adjustable laser beam size, can control the size of the heat-affected zone and the fusion zone.
- Precise and solid welded seams, airtight and watertight, good sealing performance.
- Small size, easy operation, low cost and easy maintenance.
Thulium doped fiber lasers have an emission spectrum in the range of 1.4μm-2μm, and many polymers have high absorption in these wavelengths. Thulium doped fiber lasers do not require material modification or other infrared absorbing layers to enhance the polymer's absorption of the laser light. FIBO developed the 2μm thulium-doped fiber laser in 2013, with a center wavelength of 1940nm and power instability of <2%. Due to the 2μm wavelength characteristics, it has a high absorption rate for most plastic materials, and therefore it is widely used in welding of various plastics in the medical, automotive, and consumer electronics industries.
Technical advantages of 2μm thulium-doped fiber laser:
- Excellent quality: self-developed and selected grating and other key core components.
- Excellent technology: infrared pumping source for solid-state lasers.
- Wide range of wavelengths: output wavelengths covering 1940, 1980 and other special wavelengths.
- Mature products: 5W-200W, diversified product choices.
- Support for customization: compact structure, can be customized 5W-240W
- Support customization: compact structure, can be customized 5W-240W Integration flexibility: moderate size, saving integration space
- High-quality welding: automated non-contact welding, no residue
Cell culture plate laser welding process:
Cell culture plates can be divided into flat bottom and round bottom (U-type and V-type) according to the different shapes of the bottom, and the number of culture holes are 6, 12, 24, 48, 96, 384, 1536, etc. The welding test is for 96-hole cell culture plates. Under the process parameters of laser power 45W, swing width 1.2mm, helix pitch 0.1mm, swing speed 120mm/s, the weld is uniform, no porosity, no over-burning and other defects, the weld is torn away from the base material residue, and the weld is of high strength.
With the rapid development of social science and technology, the market demand for plastics is gradually expanding, and the performance requirements for products are also improving, laser welding as a new type of plastic welding, is gradually replacing the traditional welding method, the application of broad prospects, the future is promising!
