What are the advantages of laser welding
What are the advantages of laser welding, I believe that everyone in life have met a lot of welding methods, then we have more or less understand the role of laser welding in life, in fact, laser welding is not only occasional a lot of roles, but also compared to the ordinary welding technology there are a lot of advantages, then what are the advantages of laser welding?
What are the advantages of laser welding1
Laser welding compared to other welding technologies, the main advantages of laser welding are:
1, fast speed, depth, deformation is small.
2, can be at room temperature or special conditions for welding, welding equipment device is simple. For example, the laser through the electromagnetic field, the beam will not be offset; laser in a vacuum, air and some kind of gas environment can be welded, and can be welded through the glass or transparent to the beam material.
3, can weld refractory materials such as titanium, quartz, etc., and can be welded to heterogeneous materials, the effect is good.
4, laser focus, high power density, in the high-power device welding, the depth to width ratio of up to 5:1, up to 10:1.
5, can be micro-welding. Laser beam after focusing can be obtained after a very small spot, and can be accurately positioned, can be applied to high-volume automated production of micro, small workpiece group welding. (The smallest spot can be up to 0, 1mm)
6, can be welded difficult to access the parts, the implementation of non-contact long-distance welding, has great flexibility. Especially in recent years, the YAG laser processing technology in the use of fiber optic transmission technology, and the popularity of fiber optic continuous laser laser laser welding technology has been more widely promoted and applied, more convenient for automation integration.
7, the laser beam is easy to realize the beam by time and space, can be divided into light, can carry out multi-beam simultaneous processing and multi-station processing, for more precise welding provides the conditions.
However, laser welding also has certain limitations:
1, the requirements of the weldment assembly precision, and the requirements of the beam in the position of the workpiece can not have a significant offset. This is because the laser focus after the spot size is small, narrow weld, for plus filler metal materials. If the workpiece assembly precision or beam positioning accuracy does not meet the requirements, it is easy to cause welding defects.
2, the laser and its related systems cost more, a larger one-time investment.
What are the advantages of laser welding21, good laser beam quality
After the laser focus, high power density. After the high-power low-order mode laser focus, the focal spot diameter is small.
2, laser welding speed, depth, small deformation.
Due to the high power density, small holes are formed in the metal material during the laser welding process, and the laser energy is transferred to the deeper part of the workpiece through the small holes, with less lateral diffusion. Therefore, the laser beam scanning process of material fusion depth is greater. Fast speed, large welding area per unit time.
3, laser welding is particularly suitable for welding precision sensitive parts
As the laser welding machine welding aspect ratio is large, the specific energy is small, the heat-affected zone is small, the welding deformation is small, particularly suitable for welding precision and heat-sensitive parts, can be eliminated post-weld correction and secondary processing.
4, laser welding machine flexibility
Laser welding machine can realize any angle welding, can be welded difficult to access the parts; can be welded a variety of complex welded workpiece and the shape of the large irregular workpiece. Realize any angle welding has great flexibility.
5, laser welding can weld difficult to weld . Material
Laser welding can not only be used for a variety of heterogeneous metal materials between the welding, but also for titanium, nickel, zinc, copper, aluminum, chromium, niobium, gold, silver and other metals and their alloys, steel, lumbering alloys. Welding between alloy materials.
6, laser welding machine low labor costs
Due to the extremely low heat input during laser welding, the post-weld deformation is very small, you can achieve a very beautiful surface welding effect, so there is very little follow-up treatment of laser welding, which can greatly reduce or eliminate the labor on the huge polishing and leveling process.
7, laser welding machine operation is simple
Laser welding machine welding equipment is simple, easy to learn the operation process, easy to start. The professionalism of the staff does not require high, saving labor costs.
8, laser welding machine safety
High-safety welding nozzle only in contact with the metal before touching the switch to be effective, and touch the switch with body temperature sensing.
Specialized laser generators have safety precautions for operation, and laser generator protective eyewear is required for operation to minimize eye damage.
9, laser welding machine for a variety of working environments
The laser welding machine can be used in a variety of complex working environments, can be at room temperature or special conditions for welding. For example, laser welding is similar to electron beam welding in many ways. Its welding quality is slightly inferior to electron beam welding, but the electron beam can only be transmitted in a vacuum, so welding can only be carried out in a vacuum, while laser welding technology can be more advanced. Used in a wide range of work environments.
10, the welding system is highly flexible and easy to automate.
However, laser welding machines also have certain limitations. Due to the high cost of laser vacation related systems, the one-time investment cost will be higher. In addition, the laser welding machine also requires a high degree of precision in the installation of the weldment, requiring that the position of the light source on the commodity workpiece can not have a significant deviation.
What are the advantages of laser welding3Advantages
1, the focused laser beam has a high power density, fast heating speed, can realize deep melting welding and high-speed welding. As the laser heating range is small, in the same power and welding thickness conditions, welding speed, heat-affected zone is small, welding stress and deformation is small.
2, the laser can be emitted, transmission, can propagate a considerable distance in space and attenuation is very small, can be carried out over long distances or some of the difficult to access parts of the welding; laser can be bent through optical fibers, prisms and other optical methods of transmission, deflection, focusing, especially suitable for micro-parts, difficult to access the parts or long-distance welding.
3, a laser can be used for multiple workstations for different jobs, can be used for welding, but also for cutting, alloying and heat treatment, multi-purpose machine.
4, the laser in the atmosphere loss is not big, can pass through the glass and other transparent objects, suitable for in the glass made of sealed containers welded by the alloy and other highly toxic materials; laser is not affected by the electromagnetic field, there is no X-ray protection, and do not need vacuum protection.
5, you can weld the general welding method is difficult to weld the material, such as high melting point metals, and can even be used for non-metallic materials such as ceramics, plexiglass: no heat treatment after welding, suitable for some of the heat input sensitive materials welding.
Disadvantages
1, plasma shielding. In laser welding in the base material by heat melting, vaporization to form a deep melting hole, the hole is filled with metal vapor, metal gas and laser action to form a plasma cloud. Plasma cloud absorption and reflectivity is very strong, reduce the metal material to the laser absorption rate, so that the laser energy utilization is reduced. In addition, when the plasma cloud is strong, it may also produce a negative lens effect on the laser, seriously affecting the focusing effect of the laser beam.
2, poor bridging, welding seam clamping accuracy requirements. The laser spot diameter is very small, the heat effect area is small, the bridging ability is very poor, the weld joint alignment of the flatness and precision requirements are very high.
The gap width of the weld when using laser welding can not be greater than 0, 2mm, otherwise the laser through the gap is too much, the energy loss is very large. At the same time, the joints on both sides of the flatness is too poor when the welding misalignment will occur, will seriously affect the welding quality. On the one hand, this puts forward high requirements for the preparation of laser joints, on the other hand, it requires precise clamping and high technical requirements for clamping, which all increase the process requirements and welding costs. In the industrial application of the technical difficulties.
3, the high hardness of the weld, welding hot crack tendency. Laser welding power density is very high, the thermal effect of the region is very small, and the heat input is small, so the welding region will produce a very high peak temperature and temperature gradient, weld molten metal fast solidification and contraction, which will bring about two aspects of the impact: First, the hardness of the weld is very high, and sometimes may be much higher than the base material, which is limited in the application of such as ships and other special industries; Secondly, for some metal parts, especially after deep machining, there are high mechanical stress. After deep machining of the metal there is a high mechanical stress after welding the workpiece thermal cracking tendency.
4, depression and porosity. Laser welding process is generally not used to add filler material, due to the presence of parent material end gap, deep melt hole in the metal by heat vaporization, after welding the weld will sometimes exist in the depression. Welding speed is high when the metal vapor formed by welding to run out of the weld, residual in the rapid melting and solidification of the weld, but also the formation of pores.
5, the welding of highly reflective metals such as aluminum, copper, etc. is very difficult. Aluminum and copper and their alloys on the laser reflection is very high, the beginning of the reflection rate of up to 90% or more, most of the laser energy is reflected, it is difficult to form a deep melt welding of small holes.