Laser Pointers

The Factors Influencing Laser Cutting and the Measurement of Effect

10:42 AM, 17 July 2017 .. 0 comments .. Link

In the market of laser processing equipment, laser cutting is one of the most important application of laser cutting machine, cutting machine, punch substitution effect has become more and more obvious, the market is more popular following the 50mw laser pointer marking applications, is expected to cut high-end high power laser speed, high precision, and large format cutting thick plate for the characteristics of the cutting machine equipment market has a larger growth space.

red laser pointer

In laser machining, laser light emitted from the laser collimation and focusing lens by the sink of the cutting head to a point (focus), operators need to ensure that the laser beam machining in the nozzle is the center, and adjust the distance from nozzle plate surface (as the plate thickness and spray nozzle), high pressure gas, and with the completion of the green laser pointer beam cutting operation. The main influencing factors are as follows:

Focus diameter: small diameter, narrow incision, cutting large diameter and small thickness; incision width, cutting thickness; focus position: determines the shape of the workpiece surface and the spot size of incision; the best position depends on the material type and thickness; power: influence of cutting plate thickness; affect the processing efficiency and deformation; cutting speed: the need to match the power, gas flow rate is too small, can lead to the formation of cut unserchable or burr; nozzle diameter: small diameter, suitable for cutting sheet; large diameter, suitable for cutting; gas: gas purity effect of burr formation and cutting surface oxidation, gas flow rate, the thinner plate, pressure to the more; beam mode: single mode effect in thin plate cutting, multimode optical larger, energy distribution, suitable for thick plate cutting.

In the face of machined shape processing materials, wide range of flexible, blue laser pointer cutting equipment can perform complex processing requirements, with high speed, high precision and high quality to meet the application requirements of automobile, aerospace, medical and health care, plastics, electrical and electronic, textile and other industries. The judgement of its cutting effect can be mainly measured from the following aspects:

Roughness: the cutting edge has more or less the lines left by cutting, and the depth of the line determines the roughness of the cutting surface. The shallower the texture, the lower the roughness and the smoother the surface. Generally speaking, the thinner the material thickness is, the lower the roughness of the cutting surface is; the lower the surface roughness is when cutting with nitrogen or argon than the oxygen. Verticality: because the cutting beam is focused by the beam divergence and the characteristics, which resulted in cutting (especially plate cutting), the spot size at different depth thickness of material is not the same, which can not be cut surface and the plate surface of the vast reach 90 degrees, or on the surface is wide or under the surface is wide. Generally speaking, the thinner the material, the better the verticality; the better the beam quality, the better the verticality. In addition, it is also related to the relative position of the machining time spot and the material thickness direction.

Burr: excellent cutting, cutting edges shall be free of burrs, and subsequent treatment shall be required due to burrs. This is related to the specific process parameters, material type and beam quality. Deformation: as the laser pointer cutting is essentially thermal cutting, the plate inevitably exists deformation, and the excellent cutting should minimize the adverse effects as much as possible. Particular attention should be paid to the cutting of thin plates. In general, the cutting speed is faster, more narrow, cutting gas flow increases, the deformation of the smaller.

Application of Laser Technology

01:15 PM, 19 June 2017 .. 0 comments .. Link

Laser TV is not only have their own table, in the content and the current smart TV no difference. Because the use of laser TV is the TV system, and even many TV brands are also launched laser TV. Their LCD TV and laser TV use the system is similar to the same resources to provide. So use the 2000mw laser pointer TV without worrying about no content. With the gradual enrichment of network resources, laser TV online can see a lot of high-definition content, the latest TV series, movies and entertainment programs can use the laser TV to watch. Past the projector needs a separate device, connect the player or a variety of boxes can see a large, this way OUT out. Laser TV is to see to see, do not worry about no see.

First, not the same place is the light source, laser light source life is very long, easily tens of thousands of hours to laser TV life comparable to LCD TV. Can be said that a laser TV use a three or five years is not a problem, no longer worry about the problem of light, this life cycle has been enough, after all, not all families have to use a TV for 10 years 20 years. Second, the laser TV is a reflection of the ultra-short focus of the technology of the projector, this ultra-short focal length 3000mw laser pointer TV can be achieved within 0.5 meters distance of 100 inches of the screen. In other words, laser TV can be placed in the TV cabinet on the projection of 100 inches, in the past the projector hoisting in the middle of the living room situation gone.

But laser weapons have advantages and disadvantages. For example, in the rain or dust weather, its combat effectiveness will be greatly reduced. The development of laser weapons in the United States, mainly facing the choice of high-energy laser weapons twists and turns, a variety of key technologies have yet to be overcome, research and development costs overdraft progress delay, laser weapons to be miniaturization and other issues, the existence of these problems is also greatly limited The development of burning laser pointer weapons has become a major obstacle to the installation of laser weapons.

Laser TV is able to achieve 100-inch screen, but the screen brightness enough? Brightness is not enough, the screen size is large, but the display is difficult to guarantee. So the brightness is not high, is a laser TV challenge a foundation of LCD. Now the laser TV brightness is basically 3000 lumens. But the rapid development of high power laser pointer light technology is expected in the second half of the release of new products, many began to configure a 4000 or even 5000 lumens of brightness. This brightness and then with the anti-light curtain, even if the lights to watch, the effect is also very to force. Laser TV brightness breakthrough so that this product no longer appear during the day can not be used at night must be dark paint to show the situation. So the brightness of the breakthrough is always a main line of laser TV, it is gratifying that the current laser light source brightness breakthrough faster. It is clear that the development of laser TV is not subject to brightness and stagnation.

In fact, laser weapons are a directional energy weapon. According to different combat purposes, can be divided into tactical laser weapons and strategic laser weapons two categories. Which tactical laser weapons is the use of 5000mw laser pointer as energy, as conventional weapons, as the enemy directly to the enemy, tank aircraft, such as killing damage, combat distance of 20km or so. The strategic laser weapons is more like a "big kill device", can attack thousands of miles away from the intercontinental missiles, but also attack the reconnaissance satellites in space and communications satellites. It can be said that high-base high-energy laser weapons is an ideal weapon to seize the advantages of space, so the world's major military powers are spending money to research and development.

Semiconductor Luminescent Lasers

10:44 AM, 15 May 2017 .. 0 comments .. Link

The following describes the advantages of semiconductor surface emitting lasers, structure, application, the current situation and other basic conditions. The advantages of semiconductor surface emitting lasers represent the comparison of semiconductor surface emitting lasers with side luminescent lasers. Both lasers are laminated on a semiconductor substrate, including a semiconductor epitaxial growth layer including a light emitting layer. In the side-emitting type semiconductor, a light beam is emitted from the crystal surface obtained when the semiconductor substrate is split. In the surface emitting most powerful laser pointer, a circular beam is emitted from the surface of the semiconductor epitaxial layer. It is for the original side of the luminescence of the laser left a variety of problems, showing a completely resolved prospects. The following is the advantages of surface emitting lasers.

A connection between a device such as a computer or an electronic switch or between its internal boards is used, and a large number of channel electrical wiring is used. In these electrical wiring, if the signal transmission speed of each channel becomes an order of magnitude of Gbit / s, the crosstalk of the phase can not be ignored. In addition, in the use of electrical transmission, the basic consumption. Power, but also a problem. The so-called optical interconnection technology that converts these electrical wiring into optical wiring has recently revealed head and feet. Especially in the 10 channels around the channel transmission speed of lGbit / s parallel light mutual module needs to increase. The specifications of the module in recent years have been sold overseas. As this side-by-side burning laser light source, there are now two kinds: one is a light source using a surface-emitting laser array; the other is a side-luminescent laser array. Both in a low-priced competitive state.

red laser pointer

The laser directly writes the lines on the substrate to the linear raster scan line spacing of the accuracy and controls the writing process of the experimental error, both with the experimental conditions such as photoresist properties of the treatment conditions including the substrate, the front bake, Thick scanning speed of light intensity written to the environment and the development of such a link, each link is not good, will bring the error by adjusting the light intensity, scanning speed and development of the relationship can weaken the impact of proximity effects; Of the substrate as the base, the basic elimination of the standing wave and optimization, so that the development of the embossed photoreceptor has a linear relationship between the impact of the geodesic into the spot of the quality of the grid and the cross-line 4 Conclusion and the use of 100mw laser pointer direct write device Cartesian coordinate system for single-line and multi-line characterization process, through the use of off-grid method to successfully write the line width of 9.36 / m grating and division version, the experimental results and the theoretical gap of less than 10%. The analysis of light intensity, especially in the case of out-of-focus, has a great deal of guidance on the control of the write linewidth. The experimental results show that it is entirely feasible to write a very wide line using the out-of-focus method , For the manufacture of optical components laid the experimental basis.

Laser welding process of the results of the nickel-based alloy nickel-based tungsten carbide and nickel-based tungsten carbide rare earth alloy laser cladding layer of the organization, the structure of the room temperature and high temperature hardness, corrosion resistance at room temperature and high temperature wear resistance corrosion wear performance The quantitative relationship between the corrosion wear rate, the dynamic wear rate and the dynamic corrosion rate was established on the basis of the above research, and the laser welding was applied to the mass production of the 200mw green laser cladding layer. Exhaust valve tooling fixture and automatic control device using the device on the car engine valve disc surface surface strengthening, finished rate of 98.5% The main technical performance indicators: 1. Wear resistance than GCr15 steel increased by 3 to 10 times, The corrosion resistance is 6 times higher than that of 1Cr18Ni9Ti, and the corrosion resistance is about 4 times higher than that of 2Cr13. The work is carried out: a circularly symmetrical two-dimensional pattern is depicted on a planar substrate; a circularly symmetric pattern is engraved on the curved substrate; a diffractive optical element with continuous surface relief is made on a planar substrate.

A luminescent laser at the research stage, such as a light source for a laser printer. Now the laser printer is the side of the luminescence of the laser beam emitted by mechanical vibration mirror or multi-faceted mirror separated, and thus printed. If this part of the structure into large-scale surface-emitting lasers 30mw green laser array, direct projection, then the printing speed can leap to improve the structure is also greatly simplified, which will revolution. Semiconductor surface-emitting lasers Current situation With the oscillation of different wavelengths, semiconductor surface-emitting lasers research and development situation is also very different.

Femtosecond Laser Driven Metal Wire Waveguide Helical Undulator

10:48 AM, 28 April 2017 .. 0 comments .. Link

In the electromagnetic spectrum, one of the frequency range between microwave and infrared, terahertz frequency band, has been in a mysterious veil. The exposure of terahertz waves to the public is far less than the radio waves used for communication, the microwaves in life, the X rays used in medical treatment, and the visible light that makes the eyes see the world. However, as soon as it was discovered, terahertz radiation has been regarded as one of the ten technologies to change the future".

green laser pointer

Terahertz radiation can effectively overcome the shortcomings of other bands in imaging, medical, communications and other applications. However, at present, there are still many bottlenecks in the application of THz wave, one of which is that it is difficult to obtain strong terahertz radiation source. At present, the most effective method to produce strong THz radiation is twist and modulation undulator in the periodic arrangement of magnet formed by electron blue laser pointer beam in conventional accelerators in generating high brightness coherent radiation. However, the traditional linear accelerator and electronic storage ring device has a large volume and high cost. The development of a new generation of radiation sources has been the goal of the scientific community.

Recently, the State Key Laboratory of Laser Physics, Institute of Optics and Fine Mechanics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, proposed a new concept of femtosecond laser-driven wire-wave solenoids, and conducted experiments with Nankai University's Institute of Modern Optics for the first time to use this new wave Program to achieve a strong THz radiation output.

In the experiment, the use of a beam of ultra-femtosecond femtosecond intense laser irradiation with the hair wire diameter of the wire target, through the strong interaction of the best burning laser pointer plasma to produce directional high-energy electron emission, due to the charge separation effect, Resulting in a very strong radial transient electric field; a large number of high-energy electrons emitted along the direction of the wire are guided by a radial electric field, transmitted along the wire and subjected to periodic helical motion - the equivalent of an electron beam in a micro The spiral motion in the undulator, and the non-linear amplification of the strong THz radiation output, the conversion efficiency of more than 1%.

In this work, the electron beam energy is about 100 keV and the emitter cycle is about 650 μm. The researchers changed the intensity of the radial electric field by changing the diameter of the wire to change the wavelift period and obtain the tunable strong terahertz radiation. By changing the length of the wire, the terahertz radiation intensity was observed with the transmission distance Of the amplification effect, the magnification of more than 10 times. This kind of all-optical micro-wave oscillator is a new type of undulator, which is produced by the same 300mw laser pointer at the same time. The wave device is expected to be further developed. In strong THz radiation, new light source and free Electronic laser and other related fields are widely used.

Laser Fusion

05:39 AM, 25 April 2017 .. 0 comments .. Link

According to reports, laser fusion is the use of strong laser ignition deuterium tritium fuel caused by the process of thermonuclear fusion, it is an important way to achieve controllable thermonuclear fusion. The latest progress comes from the US-based Megaz National Ignition Facility (NIF), which announced in early 2014 that the fusion energy released by the fuel core for the first time exceeded the heat absorbed by the hot spot fuel, but the fusion energy obtained from the fuel was " Nearly two orders of magnitude difference.

red laser pointer

Based on the deep analysis of the key problems in NIF fusion ignition, the new laser fusion technology is explored, and a new scheme of laser driven spherical convergent plasma fusion is proposed: the inner surface of the spherical shell containing the fusion material is directly ablated by the strong 300mw laser pointer, The high-temperature expanded high-temperature plasma, which is converged by the center of the sphere, is transformed into ionic energy after the collision of the core, and then the fusion reaction is induced. The laser-driven spherical convergent plasma fusion does not require a high compression shrinkage ratio, and a nearly one billion degree of fusion plasma fireball can be obtained at the center of the ball. It has the advantages of high energy coupling efficiency and stable yield.

The laser itself is a relatively simple and easy to control device, if it produces the beam into a very fine light beam, you can cut; defocus can be welded; and then defocus a little, can be heat treatment. The use of laser processing, not only processing speed, high efficiency, low cost, and to avoid the mold or tool replacement, shorten the production preparation time cycle. Easy to achieve continuous processing, brightest laser pointer beam transposition time is short, improve the production efficiency. Can be a variety of workpiece alternately installed. When a workpiece is machined, the finished parts can be removed and the workpiece to be machined is installed to achieve parallel machining, reduce installation time and increase the laser processing time.

The laser beam is driven by direct drive and guide. The laser can be used for rotation, tilt, up and down movement around the movement, the workpiece can be processed on the vertical surface and complex surface; and direct drive without air, high precision. The combination of 1000mw laser pointer control and robots, with the robot to move or multi-axis way to flip the parts under the beam, can be processed with some traditional methods of processing more difficult parts. Take the multi-level rapid response of the anti-collision measures, beam guide device contact the workpiece, the movement system immediately shut down, so that the system is not destroyed, to avoid the expensive maintenance; collision can quickly and simply resume work, reducing the collision caused by downtime Time, improve the processing efficiency and reliability of the laser system.

Laser head can be free to move, the current laser head has reached five sports axis, even if the workpiece is fixed in the processing, can still achieve the processing of complex parts, and as long as the use of mobile rotary table, you can process larger parts than the shaft The The best burning laser pointer beam is controlled by auto focus. The laser system linear axis can be positioned along the optical axis or any axis to keep the beam focused; the focus position is accurate at any time and the travel is unlimited. In the case of auto focus control and lens servo control, the focus lens in the lens servo system is independent of the movement of the laser system, so the focus position can not be determined.

With the further study of the interaction between lasers and materials, laser processing technology will also be widely used in flexible manufacturing systems. The flexibility of the laser processing system mainly refers to the laser processing head can be flexible to guide the laser beam to reach the parts to be processed position. Dimensional laser processing, high-power laser three-dimensional processing is the future direction of the direction of development of blue laser pointer processing, in order to achieve the flexibility of laser processing, three-dimensional laser must be in the direction of the laser processing machine, Using motion optical system. High-power three-dimensional YAG laser processing system is usually used robot (or robot) with optical fiber for beam transmission, by the robot holding the laser head to complete a variety of movement, the laser is transmitted through the optical fiber to the laser processing head, to reach the workpiece surface, which In the processing system, the beam transmission and focusing characteristics are not affected by the machining position.

Application of Laser Welding Technology in Failure Mold

11:36 AM, 29 November 2016 .. Link
The mold repair and maintenance of A-MAX steel die with crack and wear were carried out by laser welding, and the microstructure, tensile property and fatigue property of the die were analyzed. The results show that there are fine lath martensite and some white ferrite structures distributed along the grain boundary in the weld zone of the high power laser pointer welding joint. The HAZ of the joint is ferrite and pearlite. After laser welding of the mold tensile strength and elongation of the new A-MAX mold 93.95% and 88.92%, and the repair of the fatigue life of the mold has been significantly improved, and the new mold fatigue cycle times in the same order of magnitude. Mold manufacturing with the rapid development of industrial technology and expanding, in the modern manufacturing industry, especially in the field of precision manufacturing to obtain a wide range of applications, can effectively improve the utilization of materials and extend the service life of the product. With the rapid development of die-casting industry, die-casting molds on the overall mechanical properties and service life of higher demands, and because of the high cost of die-casting molds, molds in the long-term use conditions due to high-speed, high pressure, alternating hot or cold The working environment of the load causes the mold surface or the internal appearance corrosion, the wear or the crack causes the mold performance to drop, may even cause the mold to fail. The manufacture of molds involves the selection of materials, complex precision machining and associated heat treatment systems, which are expensive to manufacture and long in cycle time. Therefore, in order to avoid the mold due to cracks or wear and other forms of failure affecting production, and the use of mold repair welding technology, the technology is a die surface to solve the direct and effective method. Laser welding technology as a high-power density, energy concentration, the loss of welding consumables is small, and easy to automate the efficient high-precision welding, can achieve large penetration depth, low residual stress and deformation of the welding components, so laser pointer repair mold welding technology Because of its low cost, short cycle, good repair effect and become a common mold repair welding technology to overcome the cold welding and welding in the repair of fine mold surface defects. Test conditions: The object of the study is a cracked engine block die casting mold. The mold material is A-MAX steel. It is refined by vacuum electroslag remelting process. The hardenability is good. The service life is 3-5 times of SKD61 steel. The crack depth is 40% lower than that of SKD61 steel. The steel has excellent resistance to cracking, high temperature toughness, high temperature strength, fire resistance and high temperature strength properties for a variety of large, complex die-casting molds. During the test, acetone or absolute ethanol was used instead of industrial cleaners for surface cleaning prior to welding. Repeated cleaning was necessary to meet the welding requirements because incomplete cleaning or secondary contamination could eventually lead to a significant reduction in repair quality . Test equipment: laser welding equipment using SLC CNC laser multi-function machine, power 5KW, wavelength 10.6μm, the minimum spot diameter of 0.12mm, welding speed of 1m / min, shielding gas for argon. Test method: Tensile test was carried out by using HY-932 tensile testing machine. According to GB / T 228-2002 standard, the total length of tensile specimen is 200mm, segment length is 95mm, radius of arc is 20mm, test temperature is Room temperature. The fatigue properties of the joint were tested with QBG-25 high frequency fatigue tester. The fatigue specimen was made according to GB / T 2015111-1994. The stress ratio of cyclic stress was 0.1 and the frequency was 100Hz. In order to reduce the test error, two samples of each parallel test. Test results and analysis: can be seen from Figure 1, the center of the weld between the two plates in the phase plate. Because the base material is austenite and ferrite, the middle of the weld is fine grain structure, and the fusion zone is columnar. Because burning laser pointer welding has high peak temperature, faster welding speed and cooling rate, The heat affected zone of the laser welding of the -MAX steel mold is very small, but it can be seen that the microstructure of the heat affected zone of the joint in the mold repair is white ferrite and black pearlite structure. As can be seen from Figure 1b, A-MAX steel weld microstructure is relatively small quenching organizations, but also observed a small lath martensite and some along the grain boundary distribution of white ferrite. In addition, there is a small amount of fine precipitates in the welds of the A-MAX steel, which improves the strength of the A-MAX steel molds. Because the energy density of the laser beam is concentrated during the laser welding process, and the welding speed of the 50mw laser pointer is relatively fast, the liquid metal in the joint melting zone will solidify at a faster cooling rate, which is equivalent to a once Rapid hardening process, get the strength, hardness and plasticity of good lath martensite structure. The left figure shows the results of comparison of the tensile strength and elongation of the new mold. The tensile strength of the new A-MAX mold is 843MPa and the elongation is 9.419%. The tensile strength of the A-MAX mold is 792MPa and the elongation is 8.375%. After the repair, the tensile strength of the mold reaches new A-MAX 93.95% of the mold, the elongation of the new mold also reached 88.92%. It can be seen, after 5mw laser pointer welding repair hot work die welded joints tensile strength and elongation are very close to the new A-MAX mold, with better mechanical properties. The reason for the weld strength at the mold repair site is close to the A-MAX steel base material, because the mold repair site is the highest energy and temperature zone in the laser welding, resulting in the welding zone in the welding direction is greater than the welding temperature Ac3 line temperature, and A-MAX steel quenched and tempered composition was more evenly distributed. So that at high temperature conditions, carbon and other alloying elements can be fully diffused, easy to obtain a uniform composition of austenite organizational structure. In addition, the green laser pointer welding speed is faster, and then the weld zone will melt rapidly at a rapid rate of cooling down, and finally the formation of regularly arranged carbon-lean lath martensite and a small amount of residual ferrite, and by laser welding , The lath martensite structure obtained by welding joint is more fine. The figure on the right is the results of fatigue tests on two specimens tested on a QBG-25 high-frequency fatigue tester. Sample 1 and Sample 2 are fatigue samples of the restored mold, and Sample 3 and Sample 4 are fatigue samples of the new mold. It can be seen that the number of fatigue cycles of sample 3 is the largest, and the average of two tests is 20619 times. The average number of fatigue cycles of A-MAX mold 1 and sample 2 is 17322 times, 83.69%. It can be seen, the mold is about to scrap the use of laser repair welding after the high-frequency fatigue life is improved, close to the new A-MAX mold, and with the new mold fatigue cycle has been in the same order of magnitude. The microstructures of HAZ are ferrite and pearlite microstructure, and the microstructures of the joint HAZ are ferrite and microstructures. The tensile strength and elongation of the hot work die were 93.95% and 89.92% of that of the new A-MAX mold, and the mechanical properties of the mold after the repair were close to that of the new A-MAX mold. After 2000mw laser pointer welding repair Thermal die fatigue life of about 83.69% of new mold, with the new mold fatigue cycle has been an order of magnitude.

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The Factors Influencing Laser Cutting and the Measurement of Effect
Application of Laser Technology
Semiconductor Luminescent Lasers
Femtosecond Laser Driven Metal Wire Waveguide Helical Undulator
Laser Fusion