Laser vuam ntawm aluminium alloys
Txhuas alloys muaj qhov zoo ntawm qhov ceev, lub zog siab thiab siv tau dav hauv kev lag luam hauv tsheb, lub zog tshiab, Aerospace thiab kev tsim khoom lag luam. Tam sim no, laser vuam tau siv dav hauv kev tsim cov khoom lag luam aluminium alloy. Piv nrog rau cov txheej txheem vuam tsoos, laser vuam tuaj yeem muab kev ua haujlwm ntau dua, zoo dua vuam zoo, thiab ua tiav cov vuam vuam thiab automation ntawm cov txheej txheem nyuaj.
Laser welding yog ib qho cuab yeej siv tshuab uas siv lub tshuab hluav taws xob siab tshaj plaws rau cov hlau nto, thiab cov hlau yog yaj thiab tom qab ntawd txias thiab crystallized los ua ib qho kev sib txuas los ntawm thermal coupling ntawm laser thiab hlau. Raws li cov txheej txheem thermal ua haujlwm ntawm laser vuam, nws tuaj yeem muab faib ua ob hom: thermal conduction vuam thiab sib sib zog nqus nqus vuam. Thermal conduction vuam yog tsuas yog siv rau ntim vuam lossis micro-nano vuam ntawm precision qhov chaw; laser tob tob welding yog tsuas yog siv rau vuam cov ntaub ntawv uas yuav tsum tau ua kom tiav kev nkag mus. Ntawm lawv, cov txheej txheem vuam yuav vaporize cov khoom, thiab qhov tshwm sim ntawm qhov tseem ceeb yuav tshwm sim hauv lub pas dej molten. Nws yog feem ntau siv laser vuam txoj kev tam sim no, thiab nws kuj yog txoj kev nyiam rau aluminium alloy vuam. Cov khoom siv pabcuam, cov khoom siv vuam yooj yim, tsis muaj khoom siv, yooj yim rau automate. 02 Qhov tsis zoo: Cov kev xav tau ntawm cov yeeb yaj kiab vuam yog siab, yog li cov vuam yog yooj yim rau tog; qhov pib thiab qhov kawg ntawm qhov vuam yog ib qho yooj yim los tsim cov ntsiab lus tseem ceeb; kev ruaj ntseg ntawm cov txheej txheem vuam yog dav dav, thiab vuam tsis xws luag yog yooj yim tshwm sim. 03Case: Tsev kho kom zoo nkauj kev lag luam - 5 series aluminium alloy qhov rooj ncej vuam .
Vim lub cev muaj zog ntawm aluminium alloys, xws li tsis tshua muaj laser absorption, tsis tshua muaj boiling point ntawm alloying ntsiab, siab thermal conductivity, siab thermal expansion coefficient, kuj dav solidification kub ntau, siab solidification shrinkage, tsis tshua muaj viscosity thiab siab hydrogen absorption nyob rau hauv cov kua hauv lub xeev, thiab lwm yam., yog li defects xws li pores thiab kub tawg yog yooj yim generated thaum lub sij hawm lub laser. Ntawm lawv, porosity yog qhov feem ntau yuav muaj qhov tsis xws luag hauv cov txheej txheem ntawm aluminium alloy laser vuam. Nws yuav ua kom puas lub compactness ntawm cov hlau weld, tsis muaj zog ntawm qhov zoo ntawm qhov chaw ntawm lub vuam, thiab txo cov neeg kho tshuab zog thiab corrosion kuj ntawm vuam. Yog li ntawd, yuav tsum muaj kev ntsuas zoo. Kev ntsuas los tiv thaiv kev tsim ntawm qhov hws thiab txhim kho qhov zoo ntawm cov welding.
Laser fusion welding porosity suppression method 01 Suppresses welding porosity through pre-welding surface treatment. Pre-welding surface treatment is an effective method to control metallurgical porosity in aluminum alloy laser welds. Usually, the surface treatment methods include physical and mechanical cleaning and chemical cleaning. After comparison, the process of chemically treating the surface of the test plate (metal cleaning agent cleaning - water washing - alkali cleaning - water washing - acid washing - water washing - drying) is the best. Among them, 25NaH (sodium hydroxide) solution is used for alkaline cleaning to remove the surface thickness of the material, and 20% HN03 (nitric acid) + 2% (hydrogen fluoride) aqueous solution is used for pickling to neutralize the residual alkali solution. After the surface treatment of the test plate, the welding is carried out within 24 hours , When the test plate stays for a long time after treatment, wipe it with anhydrous alcohol before welding. 02 Suppressing welding porosity through welding process parameters The formation of weld porosity is not only related to the quality of the surface treatment of the weldment, but also related to the welding process parameters. The influence of welding parameters on the weld porosity is mainly reflected in the penetration of the weld, that is, the back The effect of aspect ratio on stomata. It can be seen from the test that when the back-to-width ratio of the weld is R>0.6, qhov sib xyaw ua ke ntawm cov saw pores hauv vuam tuaj yeem txhim kho tau zoo. Cov residue ntawm pores nyob rau hauv lub weld yog tshem tawm.
03 Los ntawm kev xaiv cov roj thaiv kom raug thiab cov nqi ntws los txhawm rau txhawm rau vuam qhov pores Kev xaiv cov roj thaiv thaiv ncaj qha cuam tshuam rau qhov zoo, kev ua haujlwm thiab tus nqi ntawm vuam. Thaum lub sij hawm laser vuam txheej txheem, qhov raug txhaj tshuaj tiv thaiv cov roj tuaj yeem txo cov qhov hws ntawm vuam. Ar (argon) thiab Nws (helium) yog siv los tiv thaiv qhov chaw ntawm vuam. Nyob rau hauv cov txheej txheem ntawm aluminium alloy laser vuam, ionization degree ntawm Ar thiab Nws mus rau lub laser yog txawv, uas ua rau sib txawv weld tsim. Qhov tshwm sim qhia tau hais tias qhov kev xaiv ntawm Ar Lub zuag qhia tag nrho porosity ntawm lub weld tau txais raws li cov shielding gas yog tsawg tshaj li ntawm weld thaum Nws raug xaiv raws li cov shielding roj. Nyob rau tib lub sijhawm, peb kuj yuav tsum tau them sai sai rau qhov tseeb tias qhov ntau ntawm cov plasma tsim los ntawm vuam tsis tuaj yeem raug cua tshuab yog tias cov roj ntws tsawg dhau (10L / min), uas ua rau lub vuam pas dej tsis ruaj khov thiab ua rau muaj qhov tshwm sim. ntawm porosity tsim. Cov pa roj ntws yog nruab nrab (li 15L / min) thiab cov ntshav tuaj yeem tau txais. Kev tswj tau zoo, cov roj tiv thaiv muaj qhov zoo tiv thaiv oxidation ntawm lub pas dej ua ke, thiab qhov porosity tsawg heev. Cov huab cua ntau dhau yog nrog cov roj ntau dhau, yog li ntawd ib feem ntawm cov roj tiv thaiv tau sib xyaw rau hauv lub pas dej molten, thiab cov porosity nce.
Kev tiv thaiv ntawm porosity tsis xws luag hauv laser vuam ntawm aluminium alloys yeej ib txwm muaj teeb meem hauv kev lag luam. Kev cuam tshuam los ntawm kev ua tau zoo ntawm cov khoom siv aluminium alloy nws tus kheej, qhov tshwm sim ntawm tsis muaj porosity hauv vuam tsis tuaj yeem zam tag nrho thaum lub sijhawm vuam, tab sis qhov porosity tsuas yog txo. Los ntawm cov txheej txheem optimization ua ntej thiab tom qab vuam, peb tau sau thiab npaj peb txoj hauv kev los txo cov porosity los ntawm kev sim rau kev siv los ntawm cov npoj yaig hauv kev lag luam. DOTSLASER laser tsis tsuas yog tsom mus rau kev tshawb fawb thiab kev tsim kho tshiab ntawm cov khoom siv laser, tab sis kuj tseem txhim kho thiab tshawb nrhiav ntau yam laser ua thev naus laus zis, thiab tos ntsoov rau kev sib tham nrog ntau tus kws tshaj lij kev lag luam los txhawb kev txhim kho laser ua tshuab hauv kuv lub teb chaws.
