Laser filling mould solders technology

Laser beam welding receives one of important facets that are application of processing technique of material of laser beam machining. 70 time basically are used at soldering thin wall material and low speed solder, solder the process belongs to heat to conduct model, stimulate ray radiation to heat namely workpiece surface, exterior quantity of heat conducts inward ministry to diffuse through heat, power of the width that passes control laser pulse, energy, peak value and repeat the parameter such as frequency, make workpiece fused, form specific bath. Because laser solders as a kind of high quality, high accuracy, low be out of shape, efficient solder with what high speed spends method, solder as the YAG laser of high power CO2 and high power and the molybdenum of perfect, metal of fiber-optic transmission technology get together bundle of field lens the development that wait is successful, make its are made in machinery, the application of the domain such as industry of microelectronics of medicine of aerospace, auto industry, pulverous metallurgy, biology is wider and wider. Current research basically is centered at the theory when CO2 laser and YAG laser beam welding receive all sorts of metal data, those who include the plasma that laser causes is prismatic, absorb, scattering character and laser beam welding receive intelligence to change control, compound solder, laser beam welding receives phenomenon and alveolus behavior, weld defects happening mechanism and prevent a method to wait, right the weldability of alloy of nickel radical heat-resisting, aluminium alloy and magnesium alloy, solder the phenomenon builds model and numeric imitate, the join of copper, aluminium alloy and steely material, heterogeneous material, the respect such as assessment of laser connect performance did certain research. Laser beam welding accepts a principle: Laser beam welding is received is the laser high strenth bundle radiation comes metallic surface, pass the interaction of laser and metal, after the metal absorbs heat energy of laser translate into to make a metal fused, cooling crystallization is formed solder. The mechanism that laser beam welding receives has two kinds: 1, heat is conducted solder to be when laser illuminate when material surface, one part laser is reflexed, one part is absorbed by material, heat heat energy of light energy translate into fused, the heat of material surface layer continues with heating up conducted pattern to deliver in material, receive two weldment frit together finally. 2, laser deep fusion welding is compared when power density stimulate illuminate of beam of light greatly to arrive when material surface, material draws heat energy of light energy translate into, material is heated to fuse to vaporization, produce much metallic steam, below the counterforce that arises when vapour exits the surface, the metallic liquid that makes fuse to all around elbow out, form indentation, as laser continuity illuminate, indentation is worn the person is deeper, after laser stops illuminate, the frit fluid circumfluence of indentation periphery, solder two weldment after refrigeration is caky in, case. These two kinds solder the material property with mechanism real ground and solder need will choose, through adjusting each welder of laser art parameter gets soldering differently mechanism. The distinction with these two kinds of the mainest way depends on: Former bath surface maintains close, and latter bath is stimulated beam of light penetrates aperture. Conduct solder to the system disturb lesser, because stimulate the radiate of beam of light to did not penetrate by solder material, so, in conducting solder process welding line is invaded not easily by gas; And when deep fusion welding, of alveolus shut ceaselessly can bring about air hole. Conduct solder and means of deep fusion welding to also can be in same solder change each other in the process, by conduct means to depend on to the change of alveolus means bring to bear on to stimulate light energy density and laser pulse duration at the peak value of workpiece. The time dependence of density of laser pulse energy can make laser solders during interaction of laser and material by a kind means transforms to another kind of means, it is namely in interaction process welding line is OK preexistence conducts pattern next formation, transform again next for alveolus means. At present the amplification of domain of application of laser beam welding, basically apply at: If medicine of industry of domain of manufacturing industry application, pulverous metallurgy, auto industry, electron, biology, other sphere is right the laser beam welding such as batteries of alloy of BT20 titanium alloy, HEl30, Li-ion is received. The characteristic that laser beam welding receives is workpiece be solderinged is out of shape dinky, have join space hardly, solder deepness / width comparing is tall, because this solders,quality solders than the tradition the method is tall. But, be like to the quality that makes sure laser beam welding is received, namely laser beam welding receives a process to monitor be being controlled with quality is the serious content that a laser uses a field, include to use all sorts of sensor such as inductance, capacitance, sound wave, photoelectricity, pass computer processing, in the light of different solder object and requirement, welding line of implementation such as dogs, blemish detects, welding line quality is monitored wait for a project, through feedback control adjustment solders craft parameter, realize automation laser beam welding to receive thereby. Solder in laser in, position of focus of beam of light is one of the most crucial control technology parameter, mix in fixed laser power solder below speed, only the focus is in the ability inside optimal position limits to win the welding line figure of deep become reconciled of the biggest frit. Solder in actual laser in, affect the factor of focal position stability to avoid and decrease, need special clamp and equipment technology, the exact extent of this kind of equipment and the quality discretion that laser solders supplement each other. One, the major attribute that laser beam welding receives and other tradition solder technical photograph is compared, the main good point that laser beam welding receives is: 1, speed fast, deepness is big, be out of shape small. 2, can undertake soldering below room temperature or special condition, solder equipment unit is simple. For example, laser traverses electromagnetism field, beam of light won't deflection; Laser is planted in vacuum, air and some solder all can be applied in gas atmosphere, can pass glass or undertake soldering to the material with transparent beam of light. Nextpage 　 　 3, can solder difficult frit material is like titanium, quartz to wait, can apply solder to opposite sex material, the result is favorable. 4, after laser focusing, power density is high, when high power parts of an apparatus solders, deep wide Bikeda 5: 1, highest can amount to 10: 1. 5, can undertake miniature solders. Very small facula can be obtained after stimulating focusing of classics of beam of light, and can exact location, in the group solder of the small, small-sized work that applicable produces at big batch automation. 6, the place that can solder to be close to hard, applying blame contact is remote solder, have very big flexibility. Especially in last few years, fiber-optic transmission technology was used in technology of YAG laser beam machining, make laser beam welding received a technology to win more extensive promotion and application. 7, stimulate beam of light of easy implementation of beam of light to press time and space prismatic, can undertake much beam of light is machined at the same time reach multitask treatment, for more accurate solder offerred a condition. But, laser beam welding receives the limitation with also existing certain: 1, requirement weldment assembles precision tall, and requirement beam of light cannot have remarkable deflection in the position on workpiece. Because,this is rain of feet of spot of laser focusing gloriole inch small, welding line is narrow, to add fill metal stuff. If workpiece assembles precision or requirement of short of of precision of fixed position of beam of light, cause very easily solder be short of regret. 2, the cost of laser and gather into one of its photograph relationship is higher, one-time investment is larger. 2, laser beam welding receives heat to conduct laser beam welding to receive is the laser high strenth bundle radiation comes metallic surface, pass the interaction of laser and metal, make a metal fused form solder. In the interaction process of laser and metal, the metal is fused it is only among them phenomenon of a kind of physics. Days can be not metal of main translate into to fuse, and with other form expression comes out, if vaporization, plasma is formed,wait. However, want to realize good melt to solder, must make a metal fused the main form that makes energy transition. For this, all sorts of physics phenomena that must produce in understanding laser and metallic interaction and the relation of these physical phenomena and laser parameter, pass control laser parameter thereby, make stimulate the energy with fused metal of translate into of light energy majority, achieve soldering goal. 3, the craft parameter 　 that laser beam welding receives 1, density of power density power is one of the most crucial parameter in laser beam machining. Use higher power density, inside limits of small second time, surface layer can heat to boiling point, produce a large number of vaporization. Accordingly, high power density is machined to material purify, if stiletto, cut, sculpture is advantageous. To inferior power density, surface layer temperature achieves boiling point to need to experience several millisecond, before surface layer vaporization, ground floor reachs melting point, easy form good melt to solder. Accordingly, in conduct model laser beam welding is received in, power density is in in limits 104~106W/CM2. 2, weaveform of pulse of laser of laser pulse weaveform solders in laser in it is a serious problem, it is more important to solder to chip especially. Stimulate beam of light to shoot when high strenth to material surface, the laser energy that metallic surface will have 60%~98% is reflexed and the loss is dropped, and reflectivity changes along with exterior temperature. During action of pulse of a laser inside, the change of metallic reflectivity is very big. 3, arteries and veins of laser pulse width is wide it is one of important parameter that pulse laser solders, its since distinguishs the important parameter that fuses at material purify and material, also be the crucial parameter that decides to process facility cost and volume. 4, to soldering from anxious quantity the influence laser of quality solders to need to leave certainly normally anxious, the power density that manages facula center because of laser focus is exorbitant, evaporate easily aperture. On each plane that leaves laser central issue, power density distributings relatively even. Have two kinds from anxious means: Leaving anxious with negative from anxious. Anxious plane is located in workpiece upper part to be leaving anxious, leave to lose conversely anxious. Press geometrical optics theory, should losing from make an issue of one equal when, density of the power on place correspondence plane is approximate and identical, but the bath figure that wins actually is different. Lose from Jiao Shi, can obtain bigger frit deep, the formation of this and bath the process is concerned. The experiment makes clear, laser heats 50~200us material begins to fuse, form fluid photograph metal and appear vaporization asking cent, form city to press vapour, and with extremely tall speed eject, give out dazzling Bai Guang. Meanwhile, system of high concentration steam makes campaign of fluid photograph metal comes bath brim, form in bath center cave. Should lose from Jiao Shi, density of material interior power is higher than the surface, easy form stronger fused, vaporization, make light energy to material more in deliver. In applying actually so, should ask frit is deep bigger when, use negative from anxious; Solder when weak data, appropriate is used leaving anxious. CNC Milling