1. High frequency induction hybrid welding technology
Electromagnetic induction is a heating method that depends on the eddy current resistance heat generated inside the workpiece. Like laser, it belongs to non-contact environment-friendly heating. With fast heating speed, it can achieve accurate control of the heating area and depth. It is especially suitable for automatic material processing, and has been widely used in industry.
2. Arc hybrid welding technology
Arc hybrid heat source welding method was proposed by British scholar Steen as early as the 1980s, but for a long time since then, scientific and technological workers have not made further research and development on it. In recent years, researchers have refocused their attention on this technology and tried to combine the advantages of laser and arc to achieve the best combination.
3. TIG composite welding
The characteristics of TIG hybrid welding laser and TIG hybrid welding are as follows: 1. Using arc to enhance laser effect, low power laser can replace high power laser to weld metal materials; 2. High speed welding is available when welding thin parts; 3. It can increase penetration, improve weld formation, and obtain high-quality welding joints; 4. It can ease the requirement of interface precision of base metal end face. For example, when the CO2 laser power is 0.8KW, the TIG arc current is 90A, and the welding speed is 2m/min, it can be equivalent to the welding capacity of a 5KW CO2 laser welder. When the 5KW CO2 laser beam is combined with a 300A TIG arc, and the welding speed is 0.5~5m/min, the penetration obtained is 1.3~1.6 times that when the 5KW CO2 laser beam is used alone.
4. Plasma arc hybrid welding
The laser plasma composite adopts coaxial mode. The plasma arc is generated by a ring electrode, and the laser beam passes through the middle of the plasma arc. The plasma arc has two main functions: 1. It provides additional energy for laser welding, improves the welding speed, and thus improves the efficiency of the entire welding process; 2. The plasma arc surrounding the laser can produce the effect of heat treatment, extend the cooling time, reduce the sensitivity of hardening and residual stress, and improve the microstructure and properties of the weld.
5. MIG composite welding
Recent research shows that laser MIG hybrid heat source welding has obvious advantages in welding medium and thick plates. By adjusting the relative position of the arc and the laser, this welding method can effectively improve the welding adaptability, improve the adaptability to large gaps, and improve the weld formation. At the same time, the input arc energy can adjust the cooling rate, thereby improving the microstructure. Under the interaction of laser and arc, the welding process becomes more stable, and the welding speed is increased while the penetration is increased. When welding, the heat input is relatively small, which means that the post welding deformation and welding residual stress are small, which can reduce the time for welding clamping, positioning, and post welding orthopedic treatment. In addition, the outstanding feature of this method is that it can fill wires more stably, so that it is easier to improve the metallurgical properties and microstructure of the weld.
6. Double laser beam welding technology
In the process of laser welding, due to the high laser power density, the welding base metal is rapidly heated, melted and vaporized, generating high-temperature metal vapor. Under the continuous action of high power density laser, it is easy to generate plasma cloud, which not only reduces the laser absorption of the workpiece, but also makes the welding process unstable. If the laser power density that continues to irradiate is reduced after the formation of large deep melting holes, and the formed large deep melting holes absorb more laser, the effect of laser on metal vapor is reduced, and the plasma cloud can be reduced or disappeared. Therefore, a pulse laser with high peak power and a continuous laser, or two pulse lasers with large difference in pulse width, repetition frequency and peak power are used for composite welding of the workpiece. During the welding process, the two lasers irradiate the workpiece together, forming large deep melting holes periodically, and then stopping the laser irradiation at the right time can make the plasma cloud very small or disappear, Improve the absorption and utilization of the laser energy of the workpiece, increase the welding penetration and improve the welding ability.
Source: Laser Home
