High Speed Laser Cladding Technology

As a surface modification technology of metal materials, laser cladding can effectively change the hardness, wear resistance, corrosion resistance and high temperature resistance of metal surfaces. For more than half a century, the technology has been continuously improved and developed in practical applications. In addition to materials and processes, high power laser pointer and powder feeding technologies have been continuously upgraded. In the 1980s and 1990s, cladding lasers were mainly CO2 lasers and YAG lasers. After 2010, semiconductor lasers (both direct output and fiber coupled output) appeared. In recent years, fiber lasers have begun to compete for the cladding market of semiconductor lasers.

At the same time, people are constantly exploring ways to improve the function of powder and laser, and invented a variety of powder feeding techniques, including preset powder feeding, side-by-side feeding and center feeding. The preset powder feeding adopts the powder laying or gravity powder feeder to preset the powder on the path through which the spot passes. The preset powder feeding technology is simple, the powder feeding process has no powder splash, the powder utilization rate is high, but the versatility is not strong. The side-by-side powder feeding adopts pneumatic method to send the powder into the spot, the side-by-side powder is divided into asymmetric side feeding powder and symmetric coaxial feeding powder, and the side feeding powder is easily affected by the moving direction, and the cladding quality is relatively high. difference. Coaxial powder feeding has good quality and versatility. Coaxial pneumatic powder feeding is a “powder-packing” technique that uses a multi-beam converging powder stream or a ring-shaped converging powder stream to surround the central military laser pointer beam. The center powder feeding is also a pneumatic powder feeding method. It is a kind of "optical powder coating" technology, which is designed to surround the center powder flow by designing a hollow beam.

Ultrafast lasers concentrate light energy in picosecond to femtosecond time intervals and focus light into areas of ultra-fine space that are smaller than the diameter of the hair, making the intensity of the electromagnetic field stronger than the force of the nucleus to its surrounding electrons. It is several times higher, and many other methods that do not exist on the earth can not achieve extreme physical conditions. At the same time, the laser energy is concentrated in such a short period of time, and a huge single pulse energy and a very high peak power are obtained. The high power density laser pulse can easily strip the outer electrons, and the electrons are separated from the atoms and form a plasma. .

Since the interaction time between the laser and the material is extremely short, the plasma has not been able to transmit energy to the surrounding material, and has been ablated from the surface of the material, which can largely avoid the melting of the material due to the long pulse width and low intensity astronomy laser pointer. And the continuous evaporation phenomenon (heat effect) ensures that the surrounding materials in the space range involved are not affected during the processing, and the processing quality is greatly improved. Ultrafast laser processing is therefore also referred to as "cold processing."

In addition, the non-contact processing of the laser can avoid the problems of chipping and cracking in the traditional machine-added cutting, high precision, no micro-cracking, chipping or chipping problems, high edge crack resistance, and edge maintaining optical performance. It does not require secondary manufacturing costs such as rinsing, grinding, polishing, etc., and reduces the cost while greatly improving the workpiece yield and processing efficiency.

In recent years, high-speed laser cladding as a new laser cladding technology has attracted widespread attention in various industries such as coal mines, steel, petrochemicals, and electric power. Recently, Zhongke Zhongmei successfully used powder feeding in high-speed green laser pointer cladding technology. They used multiple lasers to wrap the center powder, and the powder melted on the molten pool and fell into the molten pool.

Compared with the coaxial pneumatic powder feeding, the central powder feeding is characterized in that the powder is a single powder flow, and there is no mutual impact scattering of the powder flow in different directions. In addition, in the vertical down-cladding process, a lower powder feed pressure can be used, so that on the one hand, the powder flow rate is relatively slow, the powder and the laser act for a long time, and the powder is more easily melted over the molten pool. On the other hand, the lower powder flow rate also reduces the ejection between the powder flow and the substrate. The practical application shows that the splash of the high-speed cladding cladding process in the center powder feeding is obviously reduced, the spark is quite gentle, and the powder utilization rate is greatly improved.

As an important part of additive manufacturing technology, laser cladding technology is a new advanced green manufacturing technology that replaces traditional surface treatment technology. The utility model utilizes a high-energy waterproof laser pointer as a heat source, simultaneously melts the high-performance powder and the base material of the part, and forms a surface cladding layer with wear resistance and corrosion resistance on the surface of the part, which not only improves the use performance of the parts, but also prolongs the service life by two. three times. Laser cladding technology is mainly used in the surface treatment of large high-value parts, especially in the surface treatment of large iron-based rotary parts. At this stage, the related technical processes have become mature for the cladding processing of the outer surface of the part, and a wide range of applications have been realized. However, the laser cladding process for the inner wall of the part, especially the inner surface of the thin-walled part, has been the bottleneck of the application of this technology.

Application of Laser Technology in Automobile Field

Since the early 1980s, the automotive industry has been one of the main drivers of the high-power laser industry. This industry has strict requirements on the quality and reliability of laser sources. Compared to traditional manufacturing techniques, laser technology can bring greater benefits in the areas of cutting, welding and marking. Because 18650 laser pointer technology is more flexible than traditional technology and easy to automate, it can meet the core requirements of the entire industry. In the beginning, the laser was only used for simple cylindrical part welding, such as the automatic transmission components of a vehicle. Nowadays, lasers have been widely used in the process of processing the entire vehicle structure. Roof welding, door welding, three-dimensional cutting of hydroformed parts, door spring annealing, instrument panel welding, marking, etc. are just a few examples of a large number of laser applications. With the development of lightweight vehicles, new materials, new structures and new processes are constantly emerging, and the safety performance of automobiles is continuously improved.

Laser ranging technology is the first laser technology to be practically applied in the military. In the late 1960s, laser rangefinders began to be equipped with troops, which were widely used for reconnaissance surveys and weapon fire control systems because of their ability to quickly and accurately measure target distances. Laser guided weapons have high precision, simple structure, and are not susceptible to electromagnetic interference, and they play an important role in precision guided weapons. The astronomy laser pointer communication has large capacity, good confidentiality and strong anti-electromagnetic interference capability. Optical fiber communication has become the development focus of communication systems. Airborne, spaceborne laser communication systems and laser communication systems for submarines are also under development.

A tactical laser weapon made of a high-power laser can blind the human eye and disable the photodetector. stage. Anti-satellite and anti-continental ballistics using high-energy laser beams may destroy military targets such as aircraft, missiles, and satellites. The application of strategic laser weapons that are close to practical missiles is still in the exploratory stage. Due to the small laser spot, high energy density, and fast cutting speed, laser cutting can achieve better cutting quality and extremely high cutting speed and efficiency, while reducing tool wear. The use of laser welding materials can avoid deformation, increase the type of welding materials, eliminate environmental factors, high quality and efficiency.

The use of military laser pointer technology welding, its advantages are extremely high welding speed, stable welding quality, high welding precision, small thermal deformation of materials, and easy to integrate into the automation operating system, which is widely used in modern industrial production, with excellent reputation. Advanced welding methods. Laser welding has been widely used in automobiles, such as welding of automobile bodies, pipe welding, welding of automobile batteries, and plastic welding of instrument panels. Lasers have unique advantages in terms of welding strength and welding precision and speed.

Laser cutting is also one of the most frequently used laser applications. Fiber lasers and CO2 lasers can be combined with standardized 2D and 3D cutting systems to cut low carbon steel, stainless steel, aluminum and other metals. When processing different parts of a car, car manufacturers take advantage of the advantages of laser cutting, such as high cutting edge quality, low heat input, and fast processing speed. Automotive parts and materials, including a variety of metals, such as airbag fabrics and composite materials used in automotive interiors, are cut using a laser. As a flexible processing tool, the laser can be easily integrated into robots and other automation devices and provides solutions for the cutting of various automation components and materials.

In addition to traditional processes such as laser cutting and laser welding, lasers can also be used in a variety of surface treatment applications such as 532nm laser pointer hardening, laser de-layering, surface activation, and laser surfacing. In the laser surfacing process, the most well-known is laser cladding. The basic materials such as metal wire or powder can be melted by laser radiation to achieve metallurgical bonding. The dilution rate of the metal of the parent component is less than 5%. . The automotive processing industry usually uses powder for laser surfacing, which can be used as a protective film for workpieces to prevent wear and corrosion, as well as high temperature and corrosion resistance (liquid). In the automotive industry, the minimum distortion rate and high flexibility of the workpiece are two important criteria. Thermal microcracking and porosity are also avoided due to reduced heat input and the use of additive materials.

Laser Welding Technology in Medical Devices

With the advent of lasers, people gradually realized that they have strong advantages such as high brightness, monochromaticity and directionality, and they have played an important role in scientific research, military, communications and other fields. Welding technology combines with laser to form a new waterproof laser pointer welding technology, which can effectively break through the limitations of traditional welding technology, and is therefore actively used in automotive manufacturing, aerospace and other fields.

Secondly, laser welding technology has also been widely used in medical and health applications. Due to the demanding requirements of the high cleanliness of its manufacturing process, laser welding technology meets its needs. Compared with other commonly used welding techniques, the laser welding technology produces almost no welding slag and debris, and it is not necessary to add any adhesive during the welding process, so that the entire welding work can be completed in the clean room. The addition of laser welding technology has greatly promoted the development of medical devices, such as the housing of active implantable medical devices, radiopaque markers for cardiac stents, earwax protectors, balloon catheters, etc. .

Implantable medical electronic devices, such as cardiac pacemakers, implantable electrocardiographs, and neurostimulators (spinal cord stimulators, deep brain stimulators, and implantable cochlear implants), are used to manage and treat the body's physiology Conditions such as heart rate, chronic pain, Parkinson's disease or severe deafness. In the past decade, patients have rapidly increased the use of implantable medical electronic devices at double-digit rates in order to improve the quality of life. These implantable electronic devices typically consist of microelectronic circuits and batteries that provide energy. In order to protect microelectronic circuits and batteries, they need to be sealed in a metal case. If the seal is lost, the body fluid can directly penetrate into the metal package, causing short circuit failure of the microelectronic circuit and endangering the patient's life.

Laser welding technology is the most common connection and sealing technology for implantable medical devices. The metal casing of implantable medical devices generally uses titanium and titanium alloys, but titanium has a strong ability to absorb hydrogen, oxygen and nitrogen at high temperatures, so the military laser pointer welding process needs to be carried out in an inert gas-tight environment. In laser welding, the control of laser energy plays an important role in the quality of welding. The laser illuminates the metal surface, which initially reflects 60% to 80% of the laser energy. As the temperature increases, the metal absorbs the laser energy gradually. When it reaches the boiling point, it can absorb nearly 90% of the energy.

The cardiac stent, also known as the coronary stent, is a commonly used medical device in cardiac interventional surgery and has the function of dredging arterial blood vessels. The main material is stainless steel, nickel titanium alloy or cobalt chromium alloy. During the process of transmitting the heart stent to the destination, the radiopaque lines at both ends of the stent can clearly see its trace and open state. The radiopaque markers can be made of precious metals such as gold, enamel and platinum iridium. Riveting, this molding process uses a green laser pointer with a minimum spot diameter of 40 μm (0.04 mm) to weld a disc-shaped marker into a special eyelet.

The gastroscope biopsy forceps used in medical treatment need to penetrate deep into the patient's body. Therefore, the quality of the biopsy forceps is very demanding. Each component of the composition needs to meet certain tensile strength and good appearance, especially the surface is not allowed. Glitch and other situations. In the previous production process, the front end of the gastroscope biopsy forceps is combined with riveting, resistance welding, etc., and the riveting method will leave burrs and other defects on the surface of the puncture gun, and resistance welding will also produce parts. The large deformation affects the practical application of the puncture gun, and the laser welding technology has the characteristics of non-contact processing, narrow heat influence range, high efficiency, high processing precision, etc., which can realize the flawless, no groove and no crease of the medical field. No burr and no cracking requirements.

Balloon catheter laser welding is the use of laser as the source of energy for infrared welding, which can be directly applied to the surface of the plastic that absorbs the 488nm laser pointer using a laser beam to melt the plastic for welding. The advanced laser welding technology can realize the seamless connection between the balloon tip and the tube body, so that the balloon catheter can be unimpeded when propelled in the curved and narrow diseased blood vessels, the damage to the blood vessel is minimized, and the operation process is safer.

The introduction of laser welding technology is beneficial to further reduce the outer diameter of the balloon dilatation catheter tip. A schematic diagram of the laser welded balloon catheter is shown in Fig. 8. Unlike metal welding, plastic laser welding requires less laser power. The greater the welding laser power, the larger and deeper the heat-acting zone on the plastic part will cause the material to overheat, deform, or even damage, so the laser power should be reasonably selected according to the depth of melting required. The use of plastic laser welding technology in medical devices is far more than the above applications. Plastic laser welding technology is being adopted by more and more medical device manufacturers, and its application prospects will be very bright.

In addition to the application of laser welding technology to the production of medical equipment, there are many other innovative usb laser pointer processing technologies that have great potential in the manufacture of medical equipment, such as laser surface modification, laser cutting, laser drilling and laser micromachining. Research and use of advanced laser processing technology will design more high-quality, high-demand medical equipment.

Industry Development of Laser Cutting Machine

Laser cutting machine industry has developed quite rapidly in recent years. From the initial YAG equipment and CO2 equipment to the current fiber, from low-power fiber to the current 10,000-watt fiber, which shows that our blue laser pointer technology continues to improve, and now the price of laser cutting equipment compared with previous years To be much cheaper, this is a very delightful thing for friends who want to buy equipment, no matter what the industry can afford the laser, afford to use the laser.

For the majority of customers, the purchase of equipment will shop around, so the competition among peers is bound to be ultimately! Nothing more than the concern of people who buy equipment, in addition to configuration, is the price and after-sales service, which is also the competition of major manufacturers. Price competition, the most common peer competition. When you consult the same piece of power equipment, there may be tens of thousands or even hundreds of thousands of price difference between the price. When it comes to configuration and technology, many people might say that the lasers are all for others, and for those of you who are just assembling them together, you do not need any technology at all. Yes, in appearance, this is indeed the case. So many people think that the green laser pointer cutting machine industry threshold low, high profits, just a few people can pull a few. However, how much is done and how much is sold.

Grasp the rules of laser cutting machine processing factors on the processing of surface quality, you can find ways to improve the surface quality of the process measures to improve the quality of the processing surface. When the laser is cutting the sheet at high temperature, the traces of the molten material do not appear in the notch below the vertical laser beam, and instead, it is ejected at the rear of the laser beam. As a result, the curved lines are formed at the cutting edge and the lines closely follow the moving laser beam. In order to correct this problem, the feed rate is reduced at the end of the cutting process and the formation of lines can be substantially eliminated.

The cutting width generally does not affect the quality of the cut. The cutting width has an important influence only when a particularly precise profile is formed inside the part because the cutting width determines the minimum internal dimensions of the profile. As the thickness of the plate increases, the cutting width also varies with Increase. So you want to ensure that the same high precision, regardless of the width of the incision, the workpiece in the high power laser cutting machine processing area should be constant; when the material thickness of more than 18mm, the cutting edge of the verticality is very important; away from the focus, the laser The beam becomes divergent, depending on the position of the focus, the cut becomes wider toward the top or bottom. Cutting edge deviation from the vertical line a few millimeters, the more vertical edge, the higher the cutting quality.

The heat-affected zone refers to the laser cut where the area along the incision is heated. At the same time, the structure of the material itself changes. For example, some materials can harden. Heat affected zone refers to the regional structure of the internal structure changes due to high temperature; and depression and corrosion of the cutting edge of the surface has an adverse effect on the appearance of laser cutting machine. They appear in the general should avoid the cutting error; Finally, if the cutting makes the part heated rapidly, it will be deformed. This is especially important in fine workmanship, where the contours and tabs are usually only a few tenths of a millimeter wide. Controlling laser power and using short 500mw laser pointer pulses can reduce the risk of heat build-up and avoid distortion.

As said above, there are many manufacturers, the equipment sold out is very cheap, of course, with spare parts and machine tools are poor. Such manufacturers generally do not have a long-term strategic plan of sustainable development, there is no core technology. What they do is some low-end things, simple assembly is also OK, if they let them study some high-tech stuff, there is no professional talent, to give him the same configuration of components, they also create good equipment. In addition to a laser device, the machine tool is also important, the same laser, different manufacturers to make the device, and some can use for years without any major problems, but some day-to-day problems.

Analysis of the Function of Laser Fine Tuning Technology

Laser trimming is widely used in the electronics industry at present. 200mw laser pointer fine-tuning of resistors and capacitors makes it extremely small in thermal impact on the adjacent components when processing, and does not produce pollution. It is easy to be computer-controlled and has the advantages of fast speed, high efficiency and continuous monitoring and other advantages, compared with conventional fine-tuning method, but also has high precision, good reproducibility and resistance does not change over time characteristics.

Laser trimming is widely used to fine tune the parameters of thick, thin film components and circuits, including resistors, capacitors, quartz resonators, parameter tuning of monolithic filters, hybrid integrated circuit amplifiers, voltage dividers, current stabilizers, digital simulations and simulations Digital converters, high frequency oscillators, operational amplifiers, quartz crystal devices (including oscillators, filters), and fine tuning of semiconductor integrated circuits, eliminating the limitations that affect the accuracy of multiple integrated circuits.

Because the laser beam can be precisely oriented, positioned within the minimum size area, and combined with a small thermal area of action in the specified form, precision thin-film elements can be fine-tuned because there is no intermediate (chemical) process in the process and can be performed in the atmosphere In the processing, so real-time test results, and 50mw laser pointer processing process to achieve automation, with high precision, process is simple and efficient features.

The sensor is a kind of detection device that can sense the information to be measured and transform the sensed information into electrical signals or other desired forms of information output according to certain rules to meet the requirements of information transmission, processing, storage and display , record and control requirements.

Sensor features include: miniaturization, digital, intelligent, multi-functional, systematic, networked. It is to achieve automatic detection and automatic control of the most important part. The existence and development of sensors, so that the object has a sense of touch, taste and smell and other sensory, so that objects slowly become alive again. Usually according to their basic perception function is divided into ten categories of thermal components, photosensitive components, gas sensors, force sensors, magnetic sensors, humidity sensors, acoustic sensors, radiation sensitive components, color sensors and taste sensitive components.

With the development of science and technology, sensor applications are also more and more widely, but with the resistance of the sensor components resistance accuracy can not be effectively controlled, many manufacturers choose to manually adjust the resistance, so that not only the accuracy Less than the guarantee, and the efficiency is still very low; a new type of 500mw laser pointer resistance device to solve this problem, the successful application of laser resistance in the sensor industry, to solve the problem of low efficiency, low accuracy, for the majority of production manufacturers save costs.

Application of Laser Quenching Technology

Laser quenching technology and application Laser quenching technology is the use of focused laser beam rapid heating of steel surface, the phase change occurs, the formation of martensite hardened layer process.

Laser quenching high power density, cooling speed, do not need water or oil cooling medium, is a clean, fast quenching process. Compared with induction quenching, flame quenching and carburizing, the hardened layer of 3000mw laser pointer quenching is even and has high hardness (generally 1-3HRC higher than that of induction hardened), small deformation of the workpiece, easy control of the heating layer depth and heating track, and easy automation , do not need induction induction quenching, as the size of the corresponding induction coil design, the processing of large parts are not subject to carburizing and other chemical heat treatment chamber size restrictions, it is gradually replaced in many industrial areas induction hardening and chemical Heat treatment and other traditional processes.

It is especially important that the deformation of the workpiece before and after laser quenching is almost negligible, making it particularly suitable for the surface finish of parts requiring high precision. The depth of 500mw laser pointer hardened layer in accordance with the parts composition, size and shape and laser process parameters are different, generally in the range of 0.3 ~ 2.0mm. Large gear tooth surface, large shaft parts of the journal quenching, surface roughness remains unchanged, do not need follow-up machining to meet the needs of the actual working conditions. Laser fusion quenching technology is the use of laser beam to the substrate surface heated to above the melting temperature, due to the substrate within the cooling and cooling the molten layer surface rapid cooling and solidification crystallization process. The obtained fused-quenched microstructures were very dense and the microstructures along the depth direction were melted-solidified layer, phase-change hardened layer, heat-affected zone and substrate.

The laser cladding layer harder than the laser hardening layer depth, hardness, wear resistance is better. The inadequacies of this technology is that the roughness of the surface of the workpiece is damaged to a certain extent, generally requiring follow-up machining to recover. In order to reduce the roughness of the surface of the parts after the laser fusion treatment and reduce the subsequent processing volume, a special 2000mw laser pointer fused quenching coating is prepared to greatly reduce the surface roughness of the fused layer. Now the laser melting of the metallurgical industry, a variety of materials such as the roll, guide and other parts of the work, the surface roughness has been close to the level of laser quenching.

Laser quenching has been successfully applied to the surface strengthening of wearing parts in the metallurgical industry, machinery industry and petrochemical industry, especially in improving the service life of wearing parts such as rollers, guide weaves, gears and scissors blades, etc., Has made great economic and social benefits. In recent years in the mold, gears and other parts surface enhancement has also been more widely used.

Laser quenching features: quenching parts are not deformed 200mw laser pointer quenching thermal cycle fast, medium carbon steel, large shaft, almost no damage to the surface roughness. Anti-oxidation protective thin coating. Laser quenching is not cracking, precise quantitative CNC quenching. On the local, groove, groove quenching, precise positioning of CNC quenching, carbon steel. Laser quenching Clean, efficient, does not require water or oil and other cooling media Cast iron engine cylinder, quenching hardness than conventional methods, hardened layer of fine structure, good toughness.

Laser quenching technology can be a variety of rails, large gears, journals, cylinder walls, molds, shock absorbers, friction wheel, roller, roller parts surface hardening. Suitable materials for medium and high carbon steel, cast iron. Application examples of laser quenching: laser hardening enhanced cast iron engine cylinder, HB230 hardness increased to HB680, increased service life of 2 to 3 times.

Development and Application of Laser Technology

Laser anti-counterfeit label printing technology by the international printing community as the twenty-first century new printing, laser holographic anti-counterfeit labels is the use of the technology of laser-molded hologram products. Laser hologram is a combination of technology and art high-tech products, mainly used for anti-counterfeit goods trademarks and important documents, ID cards, credit cards, passports, currency and other security labels. Some famous domestic and foreign special products also use these trademarks. As an art deco, development of three-dimensional holographic product packaging materials, blue laser holographic printing technology is also widely used.

Holographic holographic products have three major characteristics: large-scale industrial production can be carried out; under the illumination of light reproduction of three-dimensional pattern, the color changes with the observation of the location changes; high productivity and low cost.

Due to the unprecedented development of the commodity economy, market competition has become increasingly fierce. Product counterfeiting has taken place repeatedly. The spread of the product is so widespread that it is far more detrimental to the quality of counterfeiting. In order to prevent forgery, scientists carried out research on anti-counterfeiting technology. After decades of research, they proposed that "laser-embossed holography" should be used instead of the existing plate-making printing trademarks, thus effectively preventing trademark counterfeiting. At present, red laser pointer hologram labels are widely used in salt, imported food, cigarettes, pharmaceuticals, home appliances and other fields. At the same time, due to the characteristics of the laser holographic packaging material beautifying packaging and security, not only for the product to increase security, but also for the product to create a high-end image, enhance product quality, so as to create a good shelf effect, more and more enterprises and Brand accepted. At present, it is widely used in tobacco, alcohol, cosmetics and other higher value-added products and pharmaceuticals, food, automotive supplies and other industries.

Many electrical industry in the appearance of sheet metal parts and complete sets of electrical components used in the installation of laser cutting machine processing technology, reducing production costs, received a better production efficiency. Laser cutting machine in the electrical industry is mainly used for the appearance of sheet metal parts and complete sets of electrical components in the installation of thin steel parts for cutting. Nowadays, after adopting this new technology in many electrical appliances factories, the product quality is raised, the production cost is reduced, the labor intensity is reduced, the traditional plate processing technology is improved, and the better production benefit is received.

Laser cutting is a high-tech developed in recent decades, which has higher cutting precision, lower roughness, higher material utilization and production efficiency than the traditional cutting process, especially in the In the area of fine cutting, high power laser cutting has something that can not be compared with conventional cutting. Laser cutting is to focus the energy to a small space, the use of high-density energy for non-contact, high-speed, high-precision cutting method.

In the process of electrical manufacturing, there are many metal parts and parts, and the shape is complex, and the process is very difficult. In the process of processing, a large number of tooling and mold are needed to ensure the quality of processing. The laser cutting technology in the electrical industry, not only can effectively solve the above problems, but also to improve processing quality, save processing and processing costs, shorten the manufacturing cycle, reduce labor and processing costs, improve processing efficiency and other large format plays an important role and value.