The research of technology of magnesium alloy laser beam machining
- source:BAGANZ CNC Machining
05mm, tangent plane ripple is small and distributinging rule, hot influence area is not apparent; Laser beam welding receives magnesium alloy, welding line figuration is good, air hole is little, hot influence area is small; Frit of laser of AZ31B magnesium alloy coagulates after processing, grain gets refining, hardness and wearability get rising. The density of foreword magnesium is 1.
78 × 103kg/m3, for aluminous 2/3, the 1/4 of steel. Magnesium alloy is had compare intensity high, than stiffness, thermal conductivity, but cutting processability and can reclaim quality, be called of 21 centuries " green " project material. In recent years, magnesium alloy material is in all sorts of housing, " Liu Hai is empty " the respect such as industry of traffic means of delivery, national defence won wide application, as the development of magnesian abstraction and deep processing technique, magnesium alloy material already made the material of the 3rd big metalloid after afterwards iron and steel and aluminium, rapid development gets inside global limits. The article in overview Laser Cutting of domestic and international magnesium alloy, laser solders, on the foundation of the technology such as laser surface modified, undertook study to the technology of laser beam machining of magnesium alloy. The laser beam machining of the material of action mechanism magnesium alloy of 1 laser and material of magnesian stage gold is the hot-working that is based on smooth fuel factor, premise is laser be absorbed by magnesium alloy material and translate into heat energy. Analyse from atomic structure theory, laser is field of high frequency electromagnetism to the action of metallic stuff the action to the free electron in material, the free electron in material is in laser produces high frequency vibration below revulsive action, send radiation through pliable but strong, change of partial vibration energy is electromagnetic wave outward radiate, the average kinetic energy of electron of the others translate into, between repass electron and crystal lattice gallop comfort process change is heat energy. Different material has very big difference to the absorption of the laser of different wavelengh, absorptivity AN, express to be: Among them: C0 is velocity of light, c0=3 × 108m/s is the wavelengh of incident laser; For the conductivity of metallic stuff. From type (1) can see, be timed by treatment material, the wavelengh of laser is shorter, material is more to the absorption of laser. A large number of free electron in the metal because the action of collect skin effect, data of development of energy of block up laser is inside, made much is reflexed, average data is so right CO2 gas laser (λ =10.
The absorptance of 6 μ M) is right YAG solid laser (λ =1.
The absorption of 06 μ M) is low. It is when laser wavelengh one constant when the value, material depends on to should stimulating the volume of absorptivity of beam of light the conductivity of material, conductivity is bigger, material is less to the absorption of laser. So, the absorption of stuff of general to the absorptance of laser metal to laser wants magnesium alloy material low. This is one of difficulty that have laser beam machining to magnesium alloy material. The cut of Laser Cutting technology of 2 magnesium alloy is the first link of deep treatment of magnesium alloy material, good cut quality is the assurance of material deep treatment. Compare with photograph of traditional cut method, laser Cutting has taller cut precision, lower surface roughness and taller manufacturing efficiency. Current, still belong to domestic and internationally to the research of magnesium alloy Laser Cutting rarely seen. We use Nd of 500W solid pulse: YAG laser undertook to plank of magnesium alloy of 4mm thick AZ31B cut craft studies. Laser is cut seam narrow fine, seam on wide 0.
45mm, medium seam wide 0.
22mm, next seaming wide 0.
35mm, cut seam verticality for 0.
05mm, tangent plane ripple is small and distributinging compasses dew. Hot influence area is not apparent, cut seamed integral width to be air plasma about the 1/4 of arc cut. But, cut next seamed surfaces to have slight oxidation appearance, tangent plane has the constituent body appearance with 80 μ thick M to be the remelting layer of brilliant waiting for an axis. Is the conclusion that craft studies to reach: ? Ji of Jian of ⒙ of a low bank of earth between fields of Miao of string of Nuo of Europe of widow of person of crab brighting Ji growing permanent teeth takes ⒙ to grow permanent teeth Yu of bracelet of lax of of Xi of Ju of of Huo of Ju of Yi heart solid head throws magpie of brighting Ji of crab of excusing Yun of of Jiao ㄖ to flinch? of M of toad of postscript Hu the Huaihe River is AZ31B magnesium alloy Laser Cutting. The weldability that the laser beam welding of appearance of macroscopical form of Laser Cutting of magnesium alloy of graph 1 AZ31B and magnesium alloy of microcosmic organization Nextpage3 receives technical magnesium alloy can be bad, it is the technical bottle that restricts magnesium alloy application beforehand one of. Solder than the tradition method, laser beam welding is received have solder fast, heat loses rate the person is low, solder be out of shape small characteristic. The research that magnesium alloy laser beam welding accepts a technology is in start level, the successive CO2 laser beam welding that receives research domestic and internationally to basically be centered in magnesium alloy to the laser beam welding of magnesium alloy is received and laser beam welding of solid pulse YAG receives two territories. German R.
Coe1h. Wait for Coelho with 2.
The Nd:Y of 2kWAG laser soldered the AZ31B magnesium alloy with thick 2mm. Got exterior figuration good, stomatic area of little, HAZ is small and without the welding line that tastes bead to be brought up apparently. Canadian H.
The Al-Kazzaz Nd:Y that uses 4kWAG laser soldered successfully the ZE41A with thick 2mm-6mm. Solder exorbitant or too low metropolis brings about power of the laser in the process density of treatment surface power is reduced, the form solders to be partial focusing from alveolus focusing change when asking, conduct pattern for heat finally. Stimulate smooth compound heat source to solder as new-style solder the technology is paid close attention to increasingly, song Gang add with laser of YAG of 400W solid pulse by axial type TIG serves as solder compound heat source, solder successfully first 2.
Plank of magnesium alloy of 5mm thick AZ31B, compound soldering frit can amount to TIG greatly to solder alone 2 times, 4 times what laser solders alone, and welding line and mother capable person tensile strength (240MPa) comparatives. Soldering to improve magnesium alloy data the to laser absorptivity in the process, sun Hao effect that studied activator to receive a process to magnesium alloy laser beam welding with laser of YAG of 500W solid pulse, the frit that oxide and chloride can increase magnesium alloy laser beam welding to receive is mixed greatly deep wide than, the reason is activator imperceptible powder is in what laser action initial stage increased pair of laser energy to absorb. The laser beam welding that we had undertaken magnesium alloy thin plate is received and stimulate recover to close solder, in studying at present thick board laser solders, for the project practice provides academic support. The technology of laser surface modified of 4 magnesium alloy as technology of laser surface modified ceaseless and perfect, finishing of magnesium alloy laser is able to bear or endure in magnesium alloy surface the application of the respect such as corrode sex, wearability more and more get the attention of domestic and international investigator. Cent of technology of laser surface modified is expressed for laser and alloy of surface of remelting, laser is changed reach Fu of laser surface frit to wait. 4.
Remelting of surface of laser of magnesium alloy of remelting of 1 laser surface makes material surface organizes grain to refine, microscopical slant analyse decreases, make blame balance appearance, cause exterior aggrandizement then, make alloy surface wearability increases. The Ghazanfar Abbas of Pakistan use 1.
The semiconductor laser of 5kW undertakes to AZ31 and AZ61 magnesium alloy exterior frit coagulates processing, the hardness of AZ31 raises frit to coagulate by the 65HV of matrix the 120HV of the layer, the hardness of AZ61 raises frit to coagulate by the 70HV of matrix the 140HV of the layer, and wear extent reduced an in part, raised its wearability. Gao Yali CO2 laser that uses 800W undertook laser surface frit coagulate to AZ91HP magnesium alloy processing. Compare with primitive magnesium alloy, frit coagulates the hardness of the layer rises about 90% the left and right sides, wearability rises 78% , be able to bear or endure corrode sex rises significantly. This is a branch brilliant is refined and frit coagulates in the layer relative to more joint action. The laser frit that we studied AZ31B with laser of 5kW crosscurrent CO2 coagulates technology, microcosmic organization sees a picture 2, can see, frit coagulates area grain is apparently a lot of less than mother capable person. Frit of laser of magnesium alloy of graph 2 AZ31B coagulates microcosmic organization 4.
The research that alloy of 2 laser surface changes surface of domestic explicit magnesium alloy to use alloy to change processing is less, main research is the wearability that uses grain of the horniness that note a person to raise alloy to change a layer. Indian Majurndar J D use laser of L0kW successive CO2 to use Al+Mn to MEZ, siC and Al+Al2O3 alloy powder undertake exterior alloy change processing, hardness raises alloy to change the 270HV of the layer by the 35HV of matrix, as a result of the existence of horniness photograph SiC, at the same time wearability got rising. The CO2 laser of the use 5kW such as Chen Changjun is right apparently beforehand buy the ZM5 of Al-Y powder undertook alloy changes processing, coating hardness can achieve 250HV-325HV, and the hardness of base material is 80HV-l00HV only. Compare with base material photograph, the coating after laser is handled is able to bear or endure corrode sex gets rising significantly. 4.
Fu of frit of 3 laser surface and laser frit coagulate, laser alloy changes photograph comparing, study domestic and internationally to Fu of frit of magnesium alloy laser opposite more active, fu of frit of magnesium alloy laser basically is mixed around the wear-resisting that raises magnesium alloy be able to bear or endure corrode sex undertakes. German Maiwald T with Al+Cu, al+Si and AlSi30 alloy powder undertake laser frit Fu to AZ91E and NEZ210, of Al+Si frit cladding be able to bear or endure corrode sex is good at Al+Cu frit cladding, of AlSi30 frit cladding be able to bear or endure corrode sex is best. German Bakkar A is in the AS41 of carbon fiber aggrandizement apparently Al-S of laser frit Fu, pulverous, got with base cease the frit cladding that has area of good have a common boundary, and of frit cladding be able to bear or endure corrode sex rose. Huang Kaijin use 3.
5kW laser is in AZ9ID surface is effective ground frit Fu blame brilliant is compound and pulverous Zr-Cu-Ni-Al/TiC, below the action that is not the compound between brilliant and metal, the hardness of frit cladding by the 100HV0 of base material.
1 raise 850HV0.
1 the left and right sides, hardness rose 7 times the left and right sides, after the TiC that add a person, hardness was to rise more 9 times the left and right sides, at the same time the wearability of frit cladding relatively base material raised 16 times. Will improve magnesium alloy structure to enlist in army through exterior modified function is an important step, will make one of important way that magnesium alloy studies, but the job of this respect, still do not quite far, can offerring the research that draws lessons from actually is can be counted on one's fingers more. The material of further research magnesium alloy of laser beam machining of 5 magnesium alloy had aroused the interest of research of world each country and development, but 70% magnesium alloy material of the left and right sides are main with cast or Die Casting the form is applied, have 10% only the left and right sides is machined with forming method thick board, thin plate, great ability and profile, forging and modular forging, accordingly, the deep treatment that develops magnesium alloy is inevitable trend. CNC Milling