Fiber-conducted laser welding machine-the new "vane" of the 3C manufacturing industry

With the development of the 3C digital industry, 3C digital products are developing at a high speed in the direction of high integration and high precision. The internal components of their products are becoming smaller and more compact, precise, and the electronic integration is high. Pulling force puts forward higher welding requirements. Because of its high-energy, high-precision, and high-directional characteristics, laser products are increasingly used in welding of internal structural parts of 3C products. For example, the popular IPHONE 4, MOTO mobile phones, NOKIA mobile phones, and Apple notebooks use a lot of laser welding technology in the production process to ensure the stability and compact size of the products.

　　 Compared with other traditional welding techniques, the main advantages of laser welding are:

　　 1. Fast speed, large depth, and small deformation.

　　2. It can be welded at room temperature or under special conditions, and the welding equipment is simple. For example, when the laser passes through the electromagnetic field, the beam will not shift; the laser can be welded in vacuum, air and certain gas environments, and can be welded through glass or materials that are transparent to the beam.

　　3. It can weld refractory materials such as titanium, quartz, etc., and can weld heterogeneous materials with good results.

　　4. After the laser is focused, the power density is high. When welding high-power devices, the aspect ratio can reach 5:1, and the highest can reach 10:1.

　　 5. Micro welding is possible. After the laser beam is focused, a small spot can be obtained, and it can be accurately positioned, which can be used in the assembly welding of micro and small workpieces that are mass-produced automatically.

　　6, the welding seam is smooth and beautiful, no need to deal with after welding or only simple processing procedure

　　7. The weld seam is of high quality and has no porosity, which can reduce and optimize the base metal impurities, the structure after welding can be refined, and the weld seam strength and toughness are at least equivalent to or even higher than the base metal

　　 8. It can weld hard-to-reach parts, and can perform non-contact long-distance welding, which has great flexibility. Especially in recent years, the use of optical fiber transmission technology in YAG laser processing technology has made laser welding technology more widely popularized and applied.

　　9. The laser beam is easy to split the beam according to time and energy, and can process multiple beams at the same time and multi-station processing, which provides conditions for more precise welding.

　　 The laser equipment introduced this time is the "optical fiber transmission laser welding machine", which has been widely used in the welding of internal structural parts of 3C digital products. Optical fiber transmission laser welding machine is a kind of laser welding equipment that couples high-energy laser beam into optical fiber, and after long-distance transmission, it is collimated into parallel light by a collimator, and then focused on the workpiece to perform welding. For parts that are difficult to be welded, the flexible transmission non-contact welding is implemented, which has greater flexibility. The laser beam of the optical fiber transmission laser welding machine can realize the splitting of time and energy, and can process multiple beams at the same time, which provides conditions for more precise welding. The optical fiber transmission welding machine has the advantages of good beam quality, thin spot, flexible installation and so on.

　　 Comparison of the advantages and disadvantages of the optical fiber transmission welding machine and the traditional hard optical path laser welding machine:

　　 What needs to be specifically mentioned here is that the real-time energy negative feedback technology is a key technology used in the 3C digital products of the optical fiber transmission laser welding machine.

 　　 energy negative feedback technology is to compare the desired output laser energy waveform with the actual output energy waveform in real time to determine the input energy of the pump lamp, and then control the output energy. Through the energy negative feedback control technology, the laser output energy can be accurately controlled within 3%, and at the same time, the following problems that cause the laser output energy to fluctuate in a large range are solved:

　　 (1) The fluctuation of mains power affects the fluctuation of laser output energy

　　 (2) The influence of the disparity of each discharge of the xenon lamp on the laser output energy

　　 (3) The aging of the xenon lamp leads to a decrease in the laser output energy

　　 (4) Factors such as changes in water flow and water temperature lead to fluctuations in laser output energy.

　　In order to maintain a stable and good processing state and reduce the rate of product defects, laser energy and its waveform are required to have good repeatability, and energy negative feedback control technology is an effective means to solve this problem. At present, only HG Lasers in Germany, Japan and China have the actual energy negative feedback technology.

　　 With the further development of laser technology, the application of laser equipment in the 3C digital industry will become more and more extensive, and laser technology will drive the industry's integrated and high-precision production.