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...

1. Shielding gas blowing method There are currently two main ways to blow shielding gas: One is side-blowing shielding gas, and the other is coaxial shielding gas. The specific choice of the two blowing methods is a comprehensive consideration of many aspects. In general, it is recommended to use the side-blowing shielding gas method. 2.Principles for selecting shielding gas blowing methods It is better to use the lateral axis for straight line welds and the coaxial axis for plane closed figures. First of all, it should be made clear that the so-called "oxidation" of the weld is only a common name. In theory, it means that the weld reacts chemically with harmful components in the air, resulting in poor weld quality. It is common that the weld metal reacts chemically with oxygen, nitrogen, hydrogen, etc. in the air at a certain temperature. Preventing the weld from being "oxidized" is to reduce or avoid contact between such harmful components and the weld metal in a high-temperature state. This high-temperature state is not just the molten molten metal, but the entire time period from when the weld metal is melted to when the molten metal solidifies and its temperature drops below a certain temperature. For example, titanium alloy welding can quickly absorb hydrogen when the temperature is above 300℃, oxygen when it is above 450℃, and nitrogen when it is above 600℃. Therefore, the titanium alloy weld needs to be effectively protected after solidification and the temperature drops below 300℃, otherwise it will be "oxidized". From the above description, it is not difficult to understand that the blown protective gas not only needs to protect the weld molten pool in time, but also needs to protect the welded and just solidified area. Therefore, side-blowing protective gas is generally used, because this protection method has a wider protection range than the coaxial protection method, especially for the area where the weld has just solidified. For engineering applications, not all products can use side-blowing protective gas. For some specific products, only coaxial protective gas can be used. Targeted selection is required based on product structure and joint form. 3. Selection of specific shielding gas blowing methods (1) Straight welds The weld shape of the product is a straight line, and the joint form can be a butt joint, lap joint, internal angle joint or lap weld joint. For this type of product, it is best to use the side-blow shielding gas method. (2) Plane closed figure welds The weld shape of the product is a closed figure such as a plane circle, a plane polygon, or a plane multi-segment line. The joint form can be a butt joint, lap joint, lap weld joint, etc. For this type of product, it is best to use the coaxial shielding gas method. The selection of shielding gas directly affects the quality, efficiency and cost of welding production. However, due to the diversity of welding materials, the selection of welding gas is also relatively com...

First, the definition of shielding gas: Why is shielding gas needed? Because during laser welding, the high-energy heat source of the laser will quickly melt the material and form a keyhole in the molten pool. The metal in the molten state is very active and easily undergoes oxidation reaction with oxygen in the atmosphere. It is very violent. Intuitively, there are a lot of spatters, pores, and welding slag everywhere, just like fireworks. Therefore, the role of shielding gas is to isolate the molten pool from oxygen. The shielding gas gushes around the molten pool to form a flowing inert gas environment, and the molten metal and oxygen are in direct contact. Another function of laser welding shielding gas is to blow away the plasma (the high-energy laser makes the metal ionize and produce a cloud of mist above the molten pool, which will shield the laser energy from reaching the molten pool directly, and the laser will have a certain loss when passing through the plasma). There are three main types of shielding gas: N2, Ar, and He. Their physical and chemical properties are different, and therefore the effects on the weld are also different. Nitrogen N2: The ionization energy of N2 is moderate, higher than that of Ar and lower than that of He. The degree of ionization under the action of laser is general, which can effectively reduce the formation of plasma cloud, thereby increasing the effective utilization rate of laser. Nitrogen can react chemically with aluminum alloy and carbon steel at a certain temperature to produce nitrides, which will increase the brittleness of the weld and reduce the toughness, and have a greater adverse effect on the mechanical properties of the weld joint. Therefore, it is not recommended to use nitrogen to protect aluminum alloy and carbon steel welds. The nitride produced by the chemical reaction of nitrogen with stainless steel can increase the strength of the weld joint, which is beneficial to the improvement of the mechanical properties of the weld, so nitrogen can be used as a shielding gas when welding stainless steel. Argon gas Ar: Ar has the lowest ionization energy, and the ionization degree is high under the action of laser, which is not conducive to controlling the formation of plasma cloud and will have a certain impact on the effective utilization rate of laser. However, Ar has very low activity and is difficult to react chemically with common metals. Moreover, Ar is not expensive. In addition, Ar has a large density, which is conducive to sinking above the weld pool and can better protect the weld pool. Therefore, it can be used as a conventional shielding gas. Helium gas He: He has the highest ionization energy, and the ionization degree is very low under the action of laser. It can well control the formation of plasma cloud. Laser can act well on metal, and He has very low activity and basically does not react chemically with metal. It is a good weld shielding gas, but the cost of He is too high. ...

The cooling system is one of the important components of the laser welding machine. If the cooling system fails, the equipment will stop working at a small level, and even the crystal rod may explode in severe cases. From this, we can see the importance of the cooling system of the laser welding machine. At present, the cooling systems of laser welding machines mainly include water cooling and air cooling systems. Among them, water cooling is the most widely used. The laser chiller is an individualized application of industrial refrigeration machines to the laser industry. It is a cooling water device that can provide constant temperature, constant flow and constant pressure. The working principle of water cooling of the laser chiller is to first inject a certain amount of water into the water tank in the machine, cool the water through the chiller cooling system, and then use the water pump to send the low-temperature cooling water to the equipment to be cooled. The cooling water in the chiller takes away the heat and then the temperature rises and flows back to the water tank to achieve the cooling effect. Its working principle is: 1. The laser welding machine chiller generally has a filter, which can effectively filter out obvious particulate impurities in the water, keep the laser pump cavity clean and prevent the possibility of water blockage. 2. The chiller uses pure water or deionized water, which is more conducive to the pump light source directly entering the laser material and can produce a better laser mode. 3. The chiller of the laser welding machine is generally equipped with a water pressure gauge, which can clearly know the water pressure in the laser waterway. 4. The chiller uses an imported compressor, the water tank and water pump are made of stainless steel, and the heat transfer coil is also made of stainless steel. This can fully ensure the stability of the chiller and the refrigeration effect. The temperature difference can be within 1°C. The lower the controlled temperature difference, the less the laser is affected by temperature. However, we recommend that the temperature difference be adjusted to about 1°C. 5. The chiller has flow protection. When the water flow is less than the set amount, there is a signal alarm, which can be used to protect the laser and related devices to be cooled. 6. The chiller of the laser welding machine has temperature protection. If the temperature is not suitable, a signal alarm will also appear. 7. The chiller has a series of adjustment functions, such as temperature adjustment and temperature difference adjustment.

The common auto parts marking methods on the market are: mold casting, electro-corrosion marking, stickers, screen printing, pneumatic marking and laser marking. Among them, although laser marking technology was born the latest, it has attracted widespread attention for its indelible marking since its birth. The main advantage of using laser for auto parts marking is that it is a fast, programmable, non-contact process with a long-lasting process that is usually not affected by the steps required in the production process or the harsh on-site environment it is subjected to. Of course, it also has disadvantages, such as the high initial cost of laser marking equipment and insufficient contrast of marking in some applications (such as marking plastic products). Laser, barcode and QR code are widely used in auto parts traceability. Barcode and QR code are popular technologies for product traceability in various forms today, and are fully applicable to all types of auto parts. Early auto parts marking mainly relied on marking serial numbers on products to meet traceability requirements. After the birth of barcodes, they were quickly applied to the identification of auto parts, but their small amount of information and poor fault tolerance prevented them from being fully popularized. This problem was not solved until the birth of QR code technology. A QR code is a 2D graphic similar to a chessboard that can hold a lot of information in a very small area. Since the 2D graphics of a QR code only require readout performance at a contrast ratio of 50% or even lower, the use of QR code graphics greatly increases the number of laser applications. The encoding of the QR code also has a built-in correction function, so the code can still be read even if part of the code is damaged for some reason. QR codes can also be decoded and encrypted in several different forms, and protection devices are placed in the data, making this type of marking more valuable for patented components. In addition to automatically generating barcodes, the marking software also supports QR code technologies such as DataMatrix, PDF417, QR Code, etc. Lasers can mark most materials used in automobiles with permanent, high-contrast marks. Laser marking machines can be used as stand-alone mass-production marking solutions for marking small workpieces, or they can be fully integrated into production lines. Flexible software control programs can customize any form of marking content. Lasers are becoming increasingly important in the automotive industry and are increasingly affecting our daily lives.

Laser marking machines use laser beams to mark permanent marks on the surfaces of various materials. The effect of marking is to expose the deep material through the evaporation of the surface material, thereby engraving exquisite patterns, trademarks and texts. In the Chinese laser industry, practitioners have made specific descriptions and classifications of it. After the enterprise customers state their requirements, they can recommend the selection of appropriate models according to the actual development situation. A. Classification of commonly used laser marking machines: 1. Fiber laser marking machine: The main technology is used to mark the required text, patterns, barcodes and other information graphics on plastic, electronic, metal, ceramic, tobacco and other material products. The fiber laser marking machine has the advantages of simple, fast and convenient operation, fast marking speed and clearness, which continuously optimizes the production management efficiency of enterprises. 2. UV laser marking machine: The industry used is the same as that of fiber laser marking machine, but the printed text, pattern, etc., when some fiber laser marking machines cannot engrave the required effect, the characteristics of UV laser marking machine are reflected, because UV laser marking machine belongs to the category of cold light, many products fiber laser marking machine cannot engrave satisfactory effect, UV laser marking machine can generally engrave. 3. Carbon dioxide laser marking machine: CO2 laser marking machine uses laser beam to mark the surface of various materials in various ways. Carve out patterns, trademarks, dates, LOGO or through text. At present, CO2 laser marking machine is mainly used in some Chinese wood, paper, etc. of enterprises. B. Advantages of laser marking machine: 1. Permanence: For example, the mark will not fade due to environmental factors (touch, acidic and reducing gases, high temperature, low temperature, etc.). 2. Anti-counterfeiting: The mark engraved by laser marking technology is not easy to copy and change, and has strong anti-counterfeiting to a certain extent. 3. Non-contact: Laser marking is processed by non-mechanical "light knife", which can print marks on any regular or irregular surface, and the workpiece will not generate internal stress after marking, ensuring the original precision of the workpiece. It does not corrode the working surface, there is no "tool" wear, no toxicity, and no pollution. 4. Wide applicability: Laser can be used as a processing method to process a variety of metals and non-metallic materials (aluminum, copper, iron, wood products, etc.). 5. High engraving accuracy: The laser marking machine engraves fine patterns on objects, with a minimum line width of 0.04mm. The marking is clear, durable and beautiful. Laser printing can meet the needs of printing a large amount of data on extremely small plastic parts. For example, it can print two-dimensional barcodes that require more...