Nyob rau hauv laser vuam, shielding roj yog ib qho tseem ceeb tivthaiv siv los tiv thaiv qhov chaw vuam los ntawm atmospheric paug. Lub siab siv laser beam siv nyob rau hauv hom vuam no ua rau muaj qhov kub thiab txias, tsim kom muaj lub pas dej molten hlau. Yog tias tsis muaj cov pa tiv thaiv no, cov hlau kub yuav ua rau cov pa oxygen, nitrogen, thiab hydrogen hauv huab cua, ua rau muaj ntau yam kev cuam tshuam ntawm vuam, xws liporosity, oxidation,lub aWelded tsis muaj zog.
Lub shielding gas, feem ntau yog ib tug inert gas los yog semi-inert gas, tsim ib tug tiv thaiv barrier nyob ib ncig ntawm lub weld cheeb tsam, tshem tawm cov huab cua puag ncig thiab zoo "shielding" lub pas dej ua ke weld los ntawm cov cua kom txog rau thaum cov hlau molten tau solidified. Qhov no tiv thaiv oxidation tsis tshwm sim thiab xyuas kom meej tias cov hlau molten tseem huv si thiab tsis muaj impurities.
Nyob rau hauv laser vuam, lub shielding gas, qee zaum hu ua 'cover gas', muaj tsib lub luag haujlwm tseem ceeb:
Tiv thaiv cov hlau hlau los ntawm kev cuam tshuam nrog ib puag ncig ib puag ncig, (xws li oxygen, nitrogen, hydrogen)
Cov roj tiv thaiv tuaj yeem tiv thaiv lub taub hau laser los ntawm cov pa phem hlau thiab cov kua tee dej sputtering.
Tiv thaiv los yog txo qis kev tsim cov ntshav ntshav, los yog huab cua ionized, uas tuaj yeem ua rau saum lub vuam. Lub plasma yog qhov tsis xav tau vim nws tuaj yeem thaiv qee qhov thiab / lossis cuam tshuam lub teeb pom kev laser. Cov hlau vapor absorbs lub laser beam thiab ionizes rau hauv cov huab plasma. Yog tias muaj cov ntshav ntau dhau lawm, lub teeb laser tau noj los ntawm cov ntshav mus rau qee qhov. Lub shielding gas yuav disperse hlau vapor plumes los yog plasma huab, txo cov kev tiv thaiv nyhuv ntawm lub laser, thiab ua rau kom cov kev siv ntawm lub laser.
Khaws cov txheej txheem ruaj khov thiab ruaj khov weld pas dej ua ke.
Txias lub vuam teeb thiab khaws lub teeb rau ntawm qhov kub thiab txias
Feem ntau, hom shielding roj siv thaum lub sij hawm muaj zog laser vuam txheej txheem tuaj yeem ua lub luag haujlwm tseem ceeb hauv cov txheej txheem thiab tuaj yeem cuam tshuam rau qhov tshwm sim los ntawm kev cuam tshuam ntawm vuam ceev, microstructure, thiab cov duab.
Feem ntau siv cov shield gases rau laser vuam yog helium, argon thiab nitrogen.