nkhani

Chifukwa chiyani stomat imawonekera?

1.1 Mkati mwa dzenje la laser welded ndi losakhazikika, ndipo kutuluka kwa dzenje ndi dziwe losungunuka kumakhala koopsa kwambiri.Mpweya wachitsulo mkati mwa dzenje umatulutsa kunja ndikupita kumpweya woumaamapangidwa pakutsegula kwa dzenje, lomwe limagudubuza mpweya woteteza (Ar) pansi pa dzenje, ndidzenje likupita patsogolo, mipweya yotetezerayi idzalowa mu dziwe losungunuka ngati mawonekedwe a thovu.Chifukwa cha kusungunuka kochepa kwambiri kwa Ar komanso kuzizira kofulumira kwa kuwotcherera kwa laser, thovulo limasiyidwa mumsoko wowotcherera asanathawe.kupanga stomata.Kuonjezera apo, zinalichifukwachitetezo osauka pa ndondomeko kuwotcherera kuti nayitrogeni alowa dziwe losungunuka kuchokera kunja, ndi kusungunuka kwa nayitrogeni mu chitsulo chamadzimadzi n'kosiyana kwambiri ndi kusungunuka kwa nayitrogeni muchitsulo cholimba.Chifukwa chake mukuziziritsa ndi kulimba kwachitsulo, kusungunuka kwa nayitrogeni kumachepa ndi kuchepa kwa kutentha pamene chitsulo chosungunula dziwe chizikhazikika mpaka kumayambiriro kwa crystallization kungayambitse kuchepa kwakukulu kwadzidzidzi mu solubility.Panthawi imeneyi, mpweya wambiri umalowa mkatikupanga thovu.Ngati mtengo woyandama wa thovu ndi wocheperako kuposa kuchuluka kwa chitsulo, ma pores amapangidwa.

Njira yowotcherera laser fusion imapondereza porosity

1. Kuletsa kuwotcherera pores ndi chisanadze kuwotcherera pamwamba mankhwala

Pre-kuwotcherera pamwamba mankhwala ndi njira zothandiza kulamulira zitsulo pores zitsulo zotayidwa aloyi laser welds.Njira zochizira pamwamba zimatha kugawidwakuthupi makina kuyeretsa ndi mankhwala kuyeretsakawirikawiri.

Pambuyo poyerekezera, kutenga njira ya mankhwala kuti mugwirizane ndi pamwamba pa bolodi loyesa (kuyeretsa zitsulo - kutsuka - kutsuka kwa alkali - kutsuka - kutsuka - kutsuka - kuyanika) ndibwino kwambiri.Pakati pawo, kutsuka kwa alkali kumachotsedwa pamwamba pa makulidwe a zinthu ndi njira yamadzimadzi ya 25% NaOH (sodium hydroxide), ndi pickling ikuchitika ndi 20% HNO3 (nitric acid) + 2% HF (hydrogen fluoride). ) njira yamadzi yochepetsera zotsalira za lye.Pambuyo pa mankhwala pamwamba pa mbale mayeso, kuwotcherera ikuchitika mkati maola 24, ndi msonkhano pamaso kuwotcherera ndi anasonkhana misozi ndi mowa anhydrous pamene mayeso mbale anaika kwa nthawi yaitali pambuyo mayeso mbale mankhwala.

2. Yesetsani kuwotcherera pores ndi kuwotcherera ndondomeko magawo

Mapangidwe kuwotcherera porosity si zokhudzana ndi khalidwe kuwotcherera pamwamba mankhwala, komanso zokhudzana kuwotcherera ndondomeko magawo.Chikoka cha kuwotcherera magawo pa pores wa kuwotcherera makamaka zimaonekera mu malowedwe a weld, ndiko, chikoka cha kumbuyo m'lifupi chiŵerengero cha weld pa pores.

Wolembakuyesatikhoza kudziwa zimenezoTingaone kuti pamene kuwotcherera kumbuyo m'lifupi chiŵerengero R ndi> 0.6, kugawa moyikirapo unyolo pores mu weld akhoza bwino bwino..Ndipo pamene chiŵerengero cha kumbuyo kwa R ndi> 0,8, kukhalapo kwa pores mumlengalenga mu weld kungakhale bwino bwino.Kuwonjezera apo, zotsalira za pores mu weld zikhoza kuthetsedwa pamlingo waukulu.

3. Yesetsani kuwotcherera pores posankha bwino kutchingira mpweya ndi kuchuluka kwa kutuluka kwake

Kusankhidwa kwa mpweya woteteza kumakhudza khalidwe, mphamvu ndi mtengo wa kuwotcherera mwachindunji.Pakuwotcherera kwa laser, kuwomba koyenera kwa gasi woteteza kumatha kuchepetsa ma weld pores bwino.

Monga momwe tawonetsera pa chithunzi pamwambapa, Ar (argon) ndi Iye (helium) amagwiritsidwa ntchito kuteteza pamwamba pa weld.M'kati mwa zitsulo zotayidwa aloyi laser kuwotcherera, Ar ndi Iye ali ndi magawo osiyanasiyana a ionization wa laser zomwe zimabweretsa mapangidwe osiyanasiyana a weld.Zitha kuwoneka kuti porosity ya weld yomwe imapezeka pogwiritsa ntchito Ar monga mpweya wotetezera ndi wocheperapo kuposa wa weld pamene Iye amasankhidwa ngati mpweya wotetezera.

Panthawi imodzimodziyo, tiyeneranso kumvetsera kuti mpweya wotuluka ndi wochepa kwambiri (<10L / min) ndi kuchuluka kwa plasmas.zopangidwa ndi kuwotcherera sizingawopsezedwe,zomwe zidzapangadziwe lowotcherera limakhala losakhazikika komanso mwayi wopanga porosity ukuwonjezeka.Ngati kuchuluka kwa mpweya wapakati (pafupifupi 15L / min) plasma imayang'aniridwa bwino ndipo mpweya woteteza umakhala ndi zotsatira zabwino zotsutsana ndi okosijeni pamadzi osungunuka.dziwe,zidzapanga porosity yaying'ono.Kuchuluka kwa gasi kumayendera limodzi ndi kupanikizika kwambiri kwa gasi, kotero kuti gawo la mpweya wotetezera umasakanizidwa mkati mwa thanki, zomwe zimapangitsa kuti porosity iwuke.

Kukhudzidwa ndi momwe zinthuzo zimagwirira ntchito, izosangathekukhala kwathunthu kupewa kuti kuwotcherera popanda kupangaporositymu njira kuwotcherera.Chomwe chingakwaniritse ndikuchitakuchepetsa porositymlingo.