Before discussing the technical details of laser welding of aluminum and aluminum alloys, we need to understand the basic working principle of laser welding machines. Laser welding machines use high-intensity laser beams to locally heat the welding area to a molten state to achieve precise metal connections. Its main components include lasers, optical systems, and welding heads. The laser generates high-energy lasers, the optical system focuses the laser beam to the welding site, and the welding head ensures the accurate positioning of the laser beam. Laser welding machines can provide a concentrated and high-power heat source, reduce the heat-affected zone and deformation, and thus improve welding quality and efficiency. Especially when welding aluminum, the precise control function of these devices can effectively deal with common problems in aluminum welding, such as pores and cracking. Modern laser welding machines are also equipped with intelligent control systems that can adjust process parameters in real time to ensure the stability and consistency of the welding process. Aluminum and aluminum alloys are widely used in construction, transportation, automobiles, electronics, packaging, and aerospace due to their light weight, high strength, and corrosion resistance. With the development of technology, the aluminum alloy welding process has been improved. Laser welding is a welding technology commonly used in the market. It has the advantages of high-power heat source concentration, small heat-affected zone, less deformation, energy saving and consumption reduction. In the daily welding process, due to the special properties of aluminum, it is difficult to control the laser focus and molten pool when laser welding aluminum and aluminum alloys; when the welder sets the process parameters improperly or lacks rich experience, problems such as pores, cracking and deformation, blackening of welds and non-fusion of undercuts may occur, which seriously affect the welding quality and performance. Next, we will introduce the difficulties and solutions encountered in welding aluminum. The main problem encountered when using laser welding aluminum is pores. During the welding process, the laser beam causes the molten pool metal to fluctuate. When the gas trapped in the metal expands and overflows, pores will appear; in addition, the aluminum oxide film will hinder the bonding between metals, absorb moisture and easily produce impurities, which will promote the formation of pores. The generation of pores will lead to weaker weld strength, reduced corrosion resistance, and unsightly welds. In general, the following measures are recommended: Adjust the appropriate laser power to ensure uniform heat input. When welding thin plates, it is recommended to increase the speed to reduce the time for gas to expand in the metal; when welding thick plates, the welding speed can be reduced to ensure performance when the material is preheated. Chemically or mechanica...

Laser cutting machine is a device that uses laser beam as a cutting tool and is widely used in cutting and processing of various materials such as metals and non-metals. 3000W laser cutting machine is a relatively common device on the market, with high cutting accuracy and efficiency. This article will introduce in detail the cutting capacity, application scope, working principle, operating precautions and other aspects of 3000W laser cutting machine. A. Cutting capacity of 3000W laser cutting machine 1. Cutting thickness The cutting thickness of 3000W laser cutting machine is affected by many factors, such as laser power, cutting speed, material type, etc. Generally speaking, the thickness range that 3000W laser cutting machine can cut is 0.5mm-20mm. Specifically: (1) For carbon steel, the thickness range that 3000W laser cutting machine can cut is 0.5mm-20mm. (2) For stainless steel, the thickness range that 3000W laser cutting machine can cut is 0.5mm-10mm. (3) For aluminum alloy, the thickness range that a 3000W laser cutting machine can cut is 0.5mm-8mm. (4) For non-ferrous metals such as copper and brass, the thickness range that a 3000W laser cutting machine can cut is 0.5mm-6mm. It should be noted that these data are for reference only, and the actual cutting effect is also affected by factors such as equipment performance and operating skills. 2. Cutting accuracy The 3000W laser cutting machine has a high cutting accuracy, which can generally reach +-0.05mm. This is mainly due to the high-precision control system and precise optical system of the laser cutting machine. In addition, the laser cutting machine also has the characteristics of non-contact cutting, which does not generate mechanical stress, thereby ensuring the flatness and accuracy of the cutting surface. 3. Cutting speed The cutting speed of a 3000W laser cutting machine is affected by factors such as material type, thickness, and cutting mode. Generally speaking, the cutting speed of a laser cutting machine can reach several meters to tens of meters per minute. Specifically: (1) For carbon steel, the cutting speed of a 3000W laser cutting machine can reach 10-30 meters per minute. (2) For stainless steel, the cutting speed of a 3000W laser cutting machine can reach 5-20 meters per minute. (3) For aluminum alloy, the cutting speed of a 3000W laser cutting machine can reach 10-25 meters per minute. (4) For non-ferrous metals such as copper and brass, the cutting speed of a 3000W laser cutting machine can reach 5-15 meters per minute. B. Scope of application of 3000W laser cutting machine 3000W laser cutting machine is widely used in metal processing, machinery manufacturing, automobile manufacturing, aerospace, electronics, medical equipment, architectural decoration and other fields. Specifically, it can be used for cutting the following materials: 1. Metal materials such as carbon steel and stainless steel. 2. Light metals such as aluminum alloy and magnesium alloy. 3. Non-...

Laser welding concentrates energy in a small range, instantly melts the welding wire and the base material to form a weld. Therefore, the welding depth after welding is large, the weld is narrow, and the speed is fast. It is suitable for self-melting welding, and usually no welding wire is needed. Of course, laser welding machines can also perform wire welding. Generally, welding wire needs to be added when the weld is larger than 1mm. The filling of welding wire makes the laser welding process more complicated. Mastering the wire feeding characteristics of laser wire welding under different welding conditions is a prerequisite for obtaining high-quality welds. Wire feeding speed is an important process parameter for laser wire welding. Reasonable selection of wire feeding speed can make full use of laser energy and improve production efficiency. The wire speed should be determined according to the gap amount of the joint. During laser welding, the welding wire is almost 100% transferred to the welding pool. Therefore, the wire feeding speed can be calculated based on the material balance of the welding process. The excess height of the weld section and the gap of the joint are both filled with welding wire. According to different welding processes, the welding wire can be fed from the front of the laser or from the back, and at a certain angle to the optical axis. In laser wire welding, the welding wire is generally required to be coplanar with the weld on the vertical plane, so that when there is a slight fluctuation in the wire feeding process, the stable transition of the molten droplet can be guaranteed. The straightness of the welding wire is very important for the stability of welding, affecting the absorption of the beam energy by the welding wire and the stability of the welding process. In order to ensure that the welding wire is delivered to the intersection of the optical axis and the base material, a copper tube is generally used to guide the welding wire at the end of the wire feeding hose, as shown in the figure. A gas pipe is installed above the workpiece to blow helium or argon gas on the side to protect the molten pool and suppress plasma. For some metals that are easily oxidized (such as titanium alloys), a special protective cover is also required to protect the molten pool and the high temperature area of the weld. Generally, the wire feeding angle is more suitable between 30° and 75°. The wire feeding position should be aligned with the center line of the weld as much as possible. When the wire feeding position deviates from the center line of the weld by 0.25mm, the melting efficiency of the 2mm welding wire will be reduced by 30%, and the melting efficiency of the 1.0mm and 1.2mm welding wires will be reduced by about 36%. Therefore, in the case of high welding requirements, the best method is to equip an optical weld tracking system for real-time monitoring and control of the welding wire position. If the wire feeding spe...

The figure above shows the calculated molten pool liquid flow velocity along the thick line in the left figure at three different welding speeds. The thick line represents the center line of the weld before and after the keyhole connection, as well as the edge of the keyhole. It can be clearly seen from the right figure that the flow velocity of the melt is significantly greater than the weld velocity due to the pressure exerted on the melt by the boiling keyhole wall. For example, at a welding speed of 100 mm/s and x=-150um, the calculated maximum liquid flow velocity exceeds 360 mm/s. It can be concluded here that if the flow is only in a two-dimensional direction, no spatter will occur, because the spatter is upwardly separated from the molten pool, and there is no axial kinetic energy on the two-dimensional surface, so the kinetic energy of the spatter can only come from the keyhole. The figure above shows that the vertical shear force of the metal vapor provides the energy source for the vertical acceleration of the spatter droplets. When the vertical flow component close to the upper surface exceeds a certain escape threshold, the spatter droplets can escape from the weld pool, as shown in the figure below. The escape threshold is determined by a combination of surface tension, surface geometry, viscosity, and local values of gravity. Surface tension is the most important consideration. The key is vz (the vertical upward flow velocity of the liquid), which is mainly related to the recoil pressure and the metal vapor shear force. The recoil pressure provides the initial kinetic energy, and the metal shear force provides the upward acceleration kinetic energy. Once the speed reaches the escape threshold, splashing is formed. Splashing influencing factor-metal shear force The vertical force balance of the molten metal around the keyhole is shown in the figure above. The main driving forces are recoil pressure and steam shear stress, and the main resistance is gravity and surface tension. According to experimental and numerical results and force balance, the high momentum of the molten metal, high recoil pressure and steam shear stress, and the low surface tension around the keyhole jointly contribute to the reason why splashing is easy to form around the keyhole. Summary: Splashing process: The generation of splashes can always be simplified into a basic sequence of phenomena: local boiling-melt acceleration-redirection of fluid flow-accumulation of vertical momentum-droplet ejection; Force analysis: recoil pressure and steam shear stress, the main resistance is gravity and surface tension; Necessary conditions for splashing: To generate splashes, the momentum of local molten droplets perpendicular to the surface of the molten pool must be sufficient to overcome the surface tension; Summary: Find out what will affect recoil pressure, shear force, and surface tension. At this time, think about whether these forces can be avoided. If they cannot...

PES LASER's handheld fiber laser welding machine, equipped with the fourth-generation swing welding gun, greatly improves the strength and quality of the welded joint and obtains better weld formability. The handheld laser welding machine can perform spot welding, straight seam welding, lap welding, girth welding and arbitrary orbital welding. The machine is also equipped with an automatic wire feeder. Compared with traditional argon arc welding, the efficiency is increased by more than 50%. Replacing the old-fashioned thermal welding system with a handheld welding gun not only facilitates the welding of molds, advertising words, kitchen utensils, doors and windows, etc., but also makes laser welding possible in outdoor operations. The welding capacity is expanded from small and lightweight workpieces to large and bulky objects that are difficult to move, such as stainless steel silos, stainless steel spiral ducts, chimney pipes, automobile steel pipe feeders, etc., with almost no size restrictions, indicating that traditional welding such as electric welding and argon arc welding will inevitably be replaced by laser welding. With the development of science and technology, traditional welding methods can no longer meet the special requirements of many industrial technologies for materials. Laser welding is the use of high-energy laser pulses to locally heat a material in a small area. The energy of laser radiation is mainly diffused to the internal information of the material through the study of heat conduction, and the material is melted to form a specific molten pool to achieve the purpose of improving welding. It is easy to operate and can weld a wider range of materials. At present, the types of materials suitable for laser welding are extremely wide, from conventional ferrous metals (such as carbon steel, alloy steel, stainless steel, etc.) to non-ferrous metals (such as aluminum alloys, magnesium alloys, copper alloys, titanium alloys, etc.), including some plastics, glass and ceramics. Laser welding (or connection) can weld the same material, and can also weld certain combinations of dissimilar materials. The laser weldability of different materials is explained below. 1. Carbon steel Generally speaking, carbon steel, especially low carbon steel, has excellent laser weldability. When the carbon equivalent of carbon steel is greater than 0.3%, the weld will have a higher hardness, but the tendency of cold cracking will increase. These two points will cause brittle fracture under fatigue and low temperature conditions. The following methods can be used to improve the situation: (1) When designing the joint, allow a certain amount of deformation (which can reduce the stress at the joint and HAZ) to reduce the tendency to crack (2) When welding materials with a carbon equivalent greater than 0.30% and materials with a carbon equivalent much less than 0.30%, using a welding bias can also reduce cracking (because it helps to reduce the carbon e...

With the rapid expansion of laser applications, more and more traditional processing fields have begun to use lasers, such as laser cutting, laser welding, laser marking, etc. The safety and protection of laser use deserves attention. The handheld fiber laser welding machine is a new generation of laser welding equipment. It belongs to non-contact welding. The operation process does not require pressurization. Its working principle is to directly irradiate a high-energy laser beam on the surface of the material. Through the interaction between the laser and the material, the material is melted inside, and then cooled and crystallized to form a weld. The handheld fiber laser welding machine fills the gap of handheld welding in the laser equipment industry, subverts the working mode of traditional laser welding machines, and replaces the previous fixed optical path with a handheld one. It is flexible and convenient, with a long welding distance, and it also makes it possible to operate laser welding outdoors. Handheld welding is mainly aimed at laser welding of long-distance and large workpieces, overcoming the limitations of the workbench travel space. The heat-affected area is small during welding, which will not cause deformation, blackening, or traces on the back of the workpiece. Moreover, the welding depth is large, the welding is firm, and the melting is sufficient. It can not only realize thermal conduction welding, but also continuous deep melting welding, spot welding, butt welding, lap welding, sealing welding, seam welding, etc. This process subverts the working mode of traditional laser welding machines. It has the advantages of simple operation, beautiful welds, fast welding speed and no consumables. It can perfectly replace traditional argon arc welding, stainless steel plates, iron plates, aluminum plates and other metal materials for welding. Laser safety training is essential for the safety and efficiency of laser welding machines during operation. During the laser welding process, high-intensity light, heat and harmful gases may be generated, which poses a potential risk to the health of operators. Through laser safety training, operators can learn how to properly use personal protective equipment, such as wearing protective glasses and masks, and how to avoid direct or indirect contact with the laser beam to ensure that the eyes and skin are effectively protected during welding work. What are the hazards of lasers: 1. Laser biological effects Lasers can cause serious skin damage, so skin protection is necessary, but eye damage is the main danger. Beam damage can be divided into three forms: Thermal: This is the result of heat generation and absorption of exposed parts, causing burns to the skin and eyes. Acoustic: This produces a mechanical shock wave, similar to the wave effect caused by throwing a pebble into a pond. Acoustic effects can cause local vaporization and tissue damage. Photochemical: Certain wavelengths can produce...

Handheld laser welding machines have outstanding welding effects in the field of thin plates, but due to improper operation or imperfect process, pores often occur during welding. When the laser welding machine is processing, the laser welding machine needs to blow out protective gas coaxially along the optical fiber to prevent the weld from oxidizing or prevent the gas splashing after the material is dissolved from contaminating the lens. The generation of pores is mostly caused by improper use of protective gas or operating errors during laser welding. The reasons for pores in different protective gases are slightly different. There are two main types of pores in the laser processing process. The following is a detailed description of these two types of pores: A. Metallurgical pores: Mainly hydrogen pores, metallurgical pores are caused by changes in the metallurgical properties and composition of the material itself during laser processing. These pores are usually caused by the following factors: 1. Material impurities: Impurities in the material volatilize at high temperatures to produce gas. 2.Changes in alloy composition: Alloy components segregate during melting and solidification to form pores. 3. Reaction-generated gas: The material reacts with the surrounding environment (such as air or protective gas) to generate gas. Features: 1. Internal generation: Pores are usually generated inside the material and have little to do with external process conditions. 2. Random distribution: Pores are unevenly distributed and vary in size and shape. 3. Material relevance: Different materials have different metallurgical properties, and the probability and properties of pores are also different. Impact: 1. Mechanical properties: Metallurgical pores will weaken the mechanical properties of the material, such as reducing strength and ductility. 2. Material consistency: The presence of pores will affect the consistency of the material and cause quality fluctuations. 3. Corrosion resistance: Pores will become the starting point of corrosion and reduce the corrosion resistance of the material. Solution: 1. Optimize material composition (1) Use high-purity materials: Reduce the impurity content in the material to reduce the probability of pore formation. (2) Improve alloy formula: Select appropriate alloy composition and proportion to reduce the possibility of segregation and gas generation. 2. Control material temperature (1) Preheating and post-heat treatment: Perform appropriate preheating and post-heat treatment before and after laser processing to reduce stress and gas generation inside the material. (2) Control cooling rate: Avoid excessive cooling to prevent gas from being trapped during solidification. 3. Use shielding gas (1) Shielding gas selection: Select appropriate shielding gas, such as argon, nitrogen, etc., to reduce the reaction between the material and oxygen in the air. (2) Gas flow control: Ensure that the flow of shielding gas is suffic...

Laser welding machine welding principle: The process principle of laser welding is to use the high energy density laser beam generated by the laser, through a focusing mirror or other optical system, to focus the beam on the surface or inside of the material to be welded, forming a small heat source area, so that the material quickly melts or vaporizes, thereby forming a molten pool or keyhole. Laser welding can be divided into molten pool mode and keyhole mode. The former is suitable for thin plates or low power welding, and the latter is suitable for thick plates or high power welding. Laser welding is divided into thermal conduction and deep fusion welding. There is almost no spatter in thermal conduction welding: thermal conduction welding is mainly achieved by heat transfer from the surface of the material to the inside, and there is almost no spatter in the process. The process does not involve violent evaporation of metal and violent physical metallurgical reactions. Deep fusion welding is the main scene for spatter: Deep fusion welding involves laser directly reaching the inside of the material, transferring heat to the inside of the material through the keyhole, and the process reaction is violent, which is the main scene for spatter. Definition of spatter: The spatter in welding refers to the molten metal droplets ejected from the molten pool during the welding process. These droplets may fall on the surrounding working surface, resulting in a rough and uneven surface, and may also cause a loss of molten pool quality, forming pits and explosion points on the weld surface, affecting the mechanical properties of the weld. Spatter classification: Small spatter: solidified droplets existing at the edge of the weld and on the surface of the material, mainly affecting the appearance, and having no effect on the performance; generally, the droplets are less than 20% of the weld molten width as the boundary for distinction; Large spatter: there is a mass loss, manifested as pits, explosion points, undercuts, etc. on the weld surface, which will lead to uneven stress stress and strain, affecting the weld performance, and mainly focus on this type of defect. Splashing process: Splashing is manifested as: the melt in the molten pool is ejected in a direction roughly perpendicular to the welding liquid surface due to high acceleration. This can be clearly seen in the figure below, where the liquid column rises from the welding molten pool and decomposes into droplets to form spatter. Scenes of spatter occurrence: To study spatter, it is necessary to understand the dynamic behavior of the deep penetration welding keyhole and the process of laser-material interaction in order to find the cause of spatter and avoid spatter from a mechanistic perspective. As shown in the figure above, some scholars used high-speed photography combined with high-temperature transparent glass to observe the movement of the keyhole during laser welding. It can be found th...