Principle and Advantages of Laser Welding Machine

Laser welding is a machine used for laser material processing, often also referred to as laser welder or laser beam welder. According to its working mode, it can usually be divided into laser mold repair welding machine (manual welding machine), automatic laser welding machine, laser spot welding machine, and optical fiber transmission laser welding machine.

Laser welding utilizes high-energy laser pulses to locally heat materials in tiny areas. The energy from laser radiation diffuses into the interior of the material through thermal conduction, melting the material to form a specific molten pool. It is a new type of welding method, mainly used for welding thin-walled materials and precision parts. It can realize spot welding, butt welding, lap welding, seal welding, etc. It features a high depth-to-width ratio, small weld width, small heat-affected zone, little deformation, fast welding speed, flat and aesthetic welds that require no post-weld treatment or only simple treatment. The weld quality is high with no pores. It allows precise control, has a small focused light spot and high positioning accuracy, and is easy to realize automation.

Therefore, the adoption of laser welding offers advantages such as high precision, high efficiency, high strength, and timeliness, ensuring quality, output, and delivery time. Currently, laser welding has become a highly competitive processing method in the precision machining industry, and is widely used for spot welding, lap welding, and seal welding of workpieces with special requirements in industries such as machinery, electronics, batteries, aviation, and instruments.

At present, the lasers mainly used in laser welding are high-power CO₂ lasers and pulsed Nd:YAG lasers. The development of lasers still focuses on the development and research of laser equipment. For example, improving the stability and service life of power supplies; for CO₂ gas lasers, solving the discharge stability of high-power lasers; for YAG solid-state lasers, developing large-capacity and long-life light pump excitation light sources. The uniform power of lasers with direct diode array laser output wavelength in the near-infrared region has reached 1kW, and the photoelectric conversion efficiency is close to 50%. These laser equipment and technologies will play a greater role in welding applications.   In the research of laser processing, beam quality and processing peripheral devices, it is necessary to study the requirements of various laser processing technologies on laser beam quality, laser beam and processing quality monitoring technologies, design and develop optical systems and processing heads, and carry out research on welding processes and materials, the requirements of welding processes on equipment, and the monitoring and control technologies of welding process parameters, so as to master the welding processes of ordinary steel, non-ferrous metals and special steel.

Laser welding involves irradiating two parts of materials with a laser beam of extremely high energy density, causing localized heating and melting, which then cools and solidifies to form an integrated joint. Compared with traditional welding processes, laser welding has the following advantages:

1. Non-contact processing, with no external force applied to the welded parts.

2. The laser energy is highly concentrated, resulting in a small heat-affected zone and minimal thermal deformation.

3. It can weld metals with high melting points, refractory and hard-to-weld metals such as titanium alloys and aluminum alloys. It can also realize welding between certain dissimilar materials.

4. The welding process is pollution-free to the environment, can be performed directly in the air, and the process is simple.

5. The welding spot is small, the weld seam is narrow, neat and aesthetic, requiring no post-weld treatment or only simple processing procedures. The weld structure is uniform with few pores and defects, which can reduce and optimize the impurities in the base material. The mechanical strength of the weld is often higher than that of the base material. Laser welding is superior to conventional welding methods in terms of mechanical properties, corrosion resistance and electromagnetic properties.

6. The laser can be precisely controlled, with a small focused light spot and high-precision positioning, enabling precision machining.

7. It is easy to be integrated with computer numerical control (CNC) systems, manipulators, or robots to realize automatic welding, thereby improving production efficiency.

Vkrlaser Optoelectronics Technology (Suzhou) Co., Ltd. has profound industry experience and mature solutions in the field of laser applications and automation equipment. For more details, please visit www.vkrlaser.com/en.