Will laser welding technology of Plastics rise suddenly

Laser processing technology has gradually penetrated into the industrial manufacturing industry and become a new technology that attracts much attention. At present, in all laser material processing applications, mainly to the manufacturing of metal parts, accounting for more than 85% of the share, the remaining 15% of the application distribution in wood and paper products, cloth and leather, fiber materials, plastics, glass, semiconductor and other non-metallic products. Different spectral wavelength ranges of laser show different absorption and efficiency of different materials, that is to say, for certain properties of materials, it is always possible to find a type of laser absorption rate is the highest, the most suitable for processing.

At present, laser processing technology of metal materials has been fully explored, including cutting, welding, cladding and cleaning. The next hot growth point, will be the laser processing of non-metallic materials, especially glass, plastic, wood and paper products is the most common type of materials in life and industry, which is more representative of plastic, its various modeling plasticity changes for a variety of industrial parts, daily necessities, application is very large. For a long time, the connection of plastics is still a problem that cannot be satisfactorily solved.

Plastic connection process Plastic has good thermoplasticity, so once the need to connect the local heating will become soft, melt, it is easy to splice together, but different methods of efficiency, splicing quality varies greatly. At present, there are mainly several ways to connect plastic parts: the first is the most traditional glue paste. At present, industrial glue often has odor, and even produces toxic substances such as formaldehyde, which does not meet the requirements of environmental protection. The second is the connection of fasteners or fasteners, such as the pre-made buckle position on two pieces of plastic, easy to remove, or screw two pieces of plastic together. The third type is the use of heat fusion plastic splicing, including induction welding, hot plate welding, hot gas welding, vibration friction welding, ultrasonic welding and laser welding. The connection between fastener and fastener has certain necessary significance. It is generally used for two plastic parts without permanent dead connection. The splicing of heat melting is generally a permanent connection between plastics. The efficiency of hot plate welding is very low, the precision is not enough, and the degree of automation is low. At present, the most used is vibration friction welding and ultrasonic welding, and the related equipment is only tens of thousands of yuan a piece, and suitable for mass production. However, ultrasonic will produce noise, welding workpiece size is limited, and easy to produce uneven heat interface, welding effect error. Laser welding plastics gradually emerge, get the attention of plastics industry.

Plastic laser welding: Plastic laser welding is a technology that uses the heat energy of laser to permanently connect thermoplastic parts. Before welding, it is necessary to add appropriate external force to clamp the area between the two parts to be welded, adjust the wavelength of the near infrared laser suitable for the material of the parts, the laser first transmitted through the first part, the second part absorbed and converted into heat energy, so as to melt the contact surface of the two parts to form a welding area and complete the welding. Plastic laser welding has the advantages of high efficiency, full automatic control, high precision, good sealing of weld, solid welding, less damage to plastic parts, without any noise, dust, is a very ideal plastic welding process. The current plastic laser welding problems, one is that the equipment is relatively expensive compared to the traditional process; Second, the welding difficulty caused by the laser absorption between different colors of plastic, especially the upper and lower layers of transparent plastic is more difficult, but in the future can explore the use of coating to assist laser absorption; Thirdly, the research on various application scenarios, loading and unloading, fixture and automation of plastic laser welding is still insufficient.

Theoretically, plastic laser welding can be applied to all industries related to plastic connection, and this technology is still in the initial exploration stage. It is used in the plastic parts of automobiles, medical instruments, household appliances, consumer electronics and so on. In automobile, the plastic laser welding machine using quasi synchronous welding is used in various combination valve body welding, check valve body welding and automobile instrument panel welding; The plastic laser welding machine with sequential contour welding mode is used for all kinds of fuel lines and plastic joints, as well as the welding of high-end car bumpers, automobile greeting lights, eddy current fans, automobile rear taillights, oil and gas separator, etc. Auto 360 camera, auto radar, automatic door lock, electronic parking controller, head up display, etc., using plastic laser welding, can obtain high product quality and economy.

In terms of medical instruments, plastic laser welding is used to seal and weld devices with high cleanliness requirements such as medical hose connection, blood analyzer, hearing aid, gastroscope connection and liquid filter tank. Consumer electronics welding, such as the use of plastic laser welding for watch band welding, VR glasses packaging, etc., can achieve beautiful appearance, high weld strength. Plastic laser welding is also used in mobile phone parts (case, headset seat, USB seat), mouse, sensor, etc. Now some enterprises have applied plastic laser welding to battery packaging welding.