Laser of high power whole solid state applies mediumly in laser frit Fu

  • Time:
  • Click:570
  • source:WEDEMEYER CNC Machining
Technology of laser surface modified is to use stimulate illuminate of beam of light to arrive when material surface, laser is absorbed to turn into by material heat energy, be heated of material surface layer warms up. Because laser power can be in centrally very small apparently, be in so very short time (heat material to high temperature namely inside 10-1 ～ 10-7S) (heat speed is as high as 105 ～ 109 ℃ / S) , make photograph of material happening solid state changes, fused even aerification evaporates. After stimulating beam of light to removed, material surface cools quickly (cooling rate is as high as 106 ℃ / S) , material surface modified can come true after cooling naturally. Technology of laser surface modified forms the processing layer of certain ply in material surface, the mechanical property that is used at improving material appearance, metallurgy function, physics function. What reach action kind according to stimulating time of the power density of beam of light and material surface action, effect is different, in industrial application at present haply cent is laser photograph to change alloy of surface of sclerosis, laser is changed, brilliant of blame of Fu of laser surface frit, laser is changed, laser pounds sclerosis and laser frit to coagulate etc. Use technology of laser surface project, the metal that has special property in Fu of frit of metallic component surface base composite material coating, to wearing away place undertakes exterior modified and aggrandizement, make the component of rehabilitate of project machine domain, important way that prolongs spare parts service life. These and capable person of low intensity mother are the frit cladding that metallurgy combines, its chemistry composition, microcosmic organization and mechanical function have than mother capable person very big rise, can acquire the exceedingly good property such as caustic of high temperature resistant, anticorrosion, wear-resisting. Because exterior coating technology can be obtained as good as matrix union, the exterior modified layer of ply moderate and in be being applied extensively at industry to produce. Technology of laser frit Fu got very rapid development inside nearly 10 years. Laser frit Fu is in Fu of metallic surface frit a hardness tall, thermal stability the craft of the good, high-powered coating that forms good metallurgy union with matrix. The dominant position that uses technology of laser frit Fu depends on managing and costly, the alloying element that has strategic value, make grain is refined, the solid dissolve that raises alloying element is spent, micromechanism is changed equably and improve the part that casts a part to slant analyse, form blame balance photograph and blame brilliant condition to wait even. Carry out a proof, technology of laser frit Fu because the virtue with its inherent itself and make progress the rapid, exterior modified method that has an outlook. Compare with photograph of traditional coat technology, technology of laser frit Fu has the craft characteristic that be as follows: Cooling rate is splitting, make caky organization is refined, produce the constituent structure that has new property even, like metastable photograph, exceed dispersion photograph, blame brilliant is equal. The structure between the layer is compact, grain is petty, general hardness is opposite taller, corrode, wear away it is better also to wait for function. The energy density that stimulates beam of light is high, effect time is short, heat rate is rapid, lesser to the hot influence of base material, cause work be out of shape lesser. Through controlling the input energy of laser, can limit base material to the attenuant action of frit cladding in extremely low rate (if quality mark is 2 ％ ～ 8 ％ ) , show with matrix the exceedingly good property with frit Fu original material held while metallurgy is united in wedlock. The choice of frit cladding material does not have any limitation almost, below a few special requirements, in Fu of frit of surface of metal of low melting point for instance Gao Rong chooses the side such as alloy, have the advantage that compares hard. Aim at through beam of light, can undertake to the area that nears hard repair perhaps undertakes electorate frit Fu, use up material little, have exceedingly good performance/price ratio. Process realizes automation control easily, and frit cladding quality is stable. Since 20 centuries 80 time begin, as the development of laser technology, appear of laser of new-style high power ceaselessly, technology of laser frit Fu is ceaseless on industrial application thorough, technology of laser frit Fu got swift and violent development, already became the heat that modified of surface of domestic and international laser studies at present. Its apply a domain to widen ceaselessly, it can be used at machinery to make make with maintenance, car, spin machinery, nautical mix with spaceflight petro-chemical wait for a domain. Already won wide application in the mechanical component such as body of cutting tool, mould, a powerful person. Technology of laser frit Fu is develop and expand of the technology ceaselessly as laser, the laser that uses to the place in equipment of laser frit Fu accordingly is its key component. At present home produces what the proprietor of an enterprise should use mostly to have CO2 gas laser, laser of solid of lamp pump YAG. Among them CO2 gas laser, power is great, average number kilowatt is taller even, but volume is huge, maintain cost tall; And CO2 laser because the structure is huge, its wavelengh is 10.

The laser of 6um cannot be passed fiber-optic conduct, flexibility gets great limitation, implement three-dimensional part not easily the frit Fu treatment of complex curved surface, cannot maintain to the spot more. Laser of solid of YAG of pump of domestic traditional lamp, power is lesser, it is 100 made of baked clay level, low-cost, volume is relatively minor also, safeguard relatively simple, but every other paragraph working hours needs to change pump Pu Deng. Because power is not great, the efficiency that its machine and applied limits suffer be restricted. At present fiber-optic coupling outputs foreign popular high-power the semiconductor laser that semiconductor laser and plastic focusing output directly will make technology of laser frit Fu, its have light produced by electricity to change efficiency tall, volume is minor wait for an advantage. But existence technology threshold is high, laser cost price is high wait for confine. And the laser of whole solid state of high power is to use semiconductor laser array to regard pump as Pu Yuan, it is working material with YAG crystal, of integrated semiconductor laser efficient advantage of as mature as YAG laser technology, have output power is great (1~5kW) , quality of beam of light is good (BPP is worth 8~40mm*mrad) , output stability is good, efficiency of changeover of light produced by electricity is good (~20% ) , flexible good, fiber-optic transmit can match robot and CNC Machining machine tool to achieve a lot of advantage such as three-dimensional treatment neatly (if pursue,1 is shown) . Laser frit Fu because its extremely high energy density, can fuse almost all alloy and pottery and porcelain. Be able to bear or endure to raise the wear-resisting of spare parts surface further corrode function, began the compound coating research that sets WC, TiC, SiC and B4C to wait for photograph of horniness of pottery and porcelain in frit of dissolvent of alloy of iron, nickel, cobalt radical extensively domestic and internationally at present. WC is the horniness material with admirable wearability, nickel radical alloy has very good wetability to WC. Accordingly, use the coating of Ni/WC pottery and porcelain with good performance of wear-resisting of preparation of technology of modified of surface of laser frit Fu to have fair academic value and applied value. But the existence is apparent interface between alloy dissolvent and photograph of horniness of pottery and porcelain and bigger function difference, appear easily grain of pottery and porcelain falls off, the problem such as stress concentration and generation crackle. In frit Fu craft to this the occurrence problem such as crackle, stoma wants to be optimized from craft on begin to solve, if optimize laser parameter craft, use warm-up and postheat processing to wait. Nextpage uses laser of high power whole solid state to be aimed at difficult problem of Fu of composite material frit of nickel radical WC to begin craft experiment research, use laser of whole solid state of 3kW high power, choose 800um core path fiber-optic transmit, cooperate a robot to achieve orbit exercise, cooperate lens of integral of beam of light to get even rectangular facula, facula size 8 × 2mm2, undertake broadband frit Fu. Frit Fu material is nickel radical pink to add grain of carbonization tungsten WC, WC grain cent is lump and ball appearance, mother capable person is material of alloy of Inconel718 high temperature. Opposite at common frit Fu, fu of laser broadband frit uses the rectangular facula that technology of plastics of beam of light gets, changed laser energy to show the inhomogenous sex of the circular gauss facula that gauss distributings, make light intensity distributings even, if the graph is shown 2 times, can form division of wider frit Fu, decreased to build greatly receive an amount, convenient undertake bedding face accumulates frit Fu, the combinative department that avoids to be taken in photograph adjacent scanning appears 2 times to heat, the limits that widened industry applies. With system of Fu of frit of laser of whole solid state of above 3kW high power, optimize craft parameter and flow, if the graph is shown 3 times,machine gotten spare parts result. Analyse result of quality of its coating metallographic, if the watch is shown 1 times, can see, no matter be lump WC grain, grain of globose still WC is in cladding of nickel radical frit all distributing equably for mass, frit cladding appears without the visible defect such as aperture of macroscopical crackle, air. Control of frit cladding ply is in 1.

Between 5mm~2mm, frit cladding from go up to be from minutes: Heat of capable person of frit cladding, frit cladding and interface of union of mother capable person, mother affects capable person of area, mother to organize 4 parts. Among them frit cladding and mother capable person are united in wedlock for metallurgy, and the attenuant rate control that mother capable person organizes to frit cladding is in 8% less than. Test of frit cladding hardness makes clear as a result, the hardness of grain of the WC in frit cladding is in limits of 2500 ± 500HV, average hardness is cladding of Ni radical frit 923.

5HV, the smallest hardness is the matrix in frit cladding 411.

7HV. The place on put together is narrated, laser of high power whole solid state is reached by right of its function characteristic in the craft advantage with distinct domain of laser frit Fu, used laser of 3kW whole solid state to develop Ni radical of laser frit Fu successfully to add the compound coating of grain of horniness of high proportion WC, obtain great application breakthrough in the industry domain such as oil machinery. CNC Milling