Ukushiswa kwe-brazing esithandweni se-vacuum kuyindlela entsha yokushiswa kwe-brazing ngaphandle kokushiswa kwe-vacuum ngaphansi kwezimo ze-vacuum. Ngenxa yokuthi ukushiswa kwe-brazing kusendaweni ye-vacuum, umphumela olimazayo womoya endaweni yokusebenza ungasuswa ngempumelelo, ngakho-ke ukushiswa kwe-brazing kungenziwa ngempumelelo ngaphandle kokusebenzisa ukushiswa kwe-flux. Kusetshenziswa kakhulu ezinsimbini zokushiswa kwe-brazing kanye ne-alloy okunzima ukuzishiswa, njenge-aluminium alloy, i-titanium alloy, i-superalloy, i-refractory alloy kanye ne-ceramics. Ijoyinti elishisiwe likhanya futhi liqinile, linezakhiwo ezinhle zomshini kanye nokumelana nokugqwala. Imishini yokushiswa kwe-vacuum ngokuvamile ayisetshenziselwa ukushiswa kwenaliti yensimbi yekhabhoni kanye nensimbi ephansi ye-alloy.
Imishini yokushisa esithandweni sokushisa i-vacuum yakhiwe kakhulu isithando sokushisa i-vacuum kanye nohlelo lokushisa i-vacuum. Kunezinhlobo ezimbili zezithando zokushisa i-vacuum: Isithando somlilo esishisayo kanye nesithando somlilo esibandayo. Izinhlobo ezimbili zezithando zingafudunyezwa ngegesi yemvelo noma ngokushisa kukagesi. Zingaklanywa zibe yi-furnace efakwe eceleni, isithando somlilo esifakwe phansi noma isakhiwo sesithando sokushisa esifakwe phezulu (uhlobo lwe-Kang), kanti uhlelo lokushisa i-vacuum lungaba yinto yonke.
Uhlelo lwe-vacuum luhlanganisa kakhulu iyunithi ye-vacuum, ipayipi le-vacuum, i-vacuum valve, njll. Iyunithi ye-vacuum ivame ukwakhiwa yipompo yemishini ye-rotary vane kanye nepompo yokusabalalisa uwoyela. Ipompo yemishini esetshenziswa kanye ingathola ngaphansi kwe-1.35 × Vacuum degree yezinga le-10-1pa. Ukuze uthole i-vacuum ephezulu, ipompo yokusabalalisa uwoyela kumele isetshenziswe ngesikhathi esifanayo, engafinyelela ku-1.35 ngalesi sikhathi × Vacuum degree yezinga le-10-4Pa. Umfutho wegesi ohlelweni ulinganiswa nge-vacuum gauge.
Ukushiswa kwe-vacuum furnace kuwukushiswa kwe-oven noma ekamelweni lokushiswa elinomoya okhishwe. Kufanelekile kakhulu ukushiswa kwe-bracing amalunga amakhulu naqhubekayo. Kufanelekile futhi ukuxhuma ezinye izinsimbi ezikhethekile, okuhlanganisa i-titanium, i-zirconium, i-niobium, i-molybdenum kanye ne-tantalum. Kodwa-ke, ukushiswa kwe-vacuum furnace nakho kunezinkinga ezilandelayo:
① Ngaphansi kwezimo ze-vacuum, insimbi kulula ukuyishintsha ibe yi-volatilize, ngakho-ke i-vacuum brazing akufanele isetshenziselwe izinto eziguquguqukayo zensimbi eyisisekelo kanye ne-solder welding. Uma kudingeka, kufanele kuthathwe izinyathelo zenqubo eziyinkimbinkimbi ezifanayo.
② I-vacuum brazing iyazwela ubulukhuni bomphezulu, ikhwalithi yokuhlanganiswa kanye nokubekezelela ukulingana kwezingxenye ezifakwe i-brazing, futhi inezidingo eziphezulu zendawo yokusebenza kanye nezinga lethiyori labasebenzisi.
③ Imishini yokuhlanza i-vacuum iyinkimbinkimbi, inemali enkulu etshalwa kanye kanye kanye nezindleko eziphezulu zokulungisa.
Ngakho-ke, ungayiqalisa kanjani inqubo yokushisisa esithandweni somoya ongcolile? Uma ukushisisa kwenziwa esithandweni somoya ongcolile, faka ukushisisa nge-welding esithandweni somoya ongcolile (noma esitsheni sokushisisa), vala umnyango wesithando somoya (noma vala isembozo sesitsha sokushisisa), bese ushisisa ngaphambi kokushisa. Qala ipompo yomshini kuqala, phendula ivalvu yokuqondisa ngemva kokuba izinga lokushisisa lifinyelele ku-1.35pa, vala indlela eqondile phakathi kwepompo yomshini kanye nesithando sokushisisa, yenza ipayipi lixhunywe nesithando sokushisisa ngepompo yokusabalalisa, usebenze ngaphakathi kwesikhathi esinqunyiwe ngokuthembela epompo yomshini kanye nepompo yokusabalalisa, faka isithando sokushisisa ezingeni lokushisisa elidingekayo, bese uqala ukushisa ngogesi.
Phakathi nenqubo yonke yokwenyuka nokushisa kwezinga lokushisa, iyunithi ye-vacuum kufanele isebenze ngokuqhubekayo ukuze igcine izinga le-vacuum esithandweni, isuse ukuvuza komoya ezindaweni ezahlukene zesistimu ye-vacuum kanye nesithando se-brazing, ukukhishwa kwegesi kanye nomhwamuko wamanzi ofakwe udonga lwesithando, i-fixture kanye ne-weldment, kanye nokuguquguquka kwensimbi ne-oxide, ukuze kuncishiswe ukwehla komoya kwangempela. Kunezinhlobo ezimbili ze-vacuum brazing: i-vacuum brazing ephezulu kanye ne-vacuum engaphelele (i-vacuum ephakathi nendawo). I-vacuum brazing ephezulu ifaneleka kakhulu ekuqiniseni insimbi eyisisekelo okunzima ukuyibolisa (njenge-nickel base superalloy). I-vacuum brazing engaphelele isetshenziselwa izimo lapho insimbi eyisisekelo noma i-solder ishintshashintsha ngaphansi kwezimo zokushisa ze-brazing kanye nezimo ze-vacuum eziphezulu.
Uma kufanele kuthathwe izinyathelo zokuphepha ezikhethekile ukuqinisekisa ubumsulwa obuphezulu, indlela yokuhlanza i-vacuum kufanele isetshenziswe ngaphambi kokushiswa kwe-hydrogen eyomile. Ngokufanayo, ukusebenzisa indlela yokuhlanza i-hydrogen eyomile noma igesi engasebenzi ngaphambi kokupompa i-vacuum kuzosiza ukuthola imiphumela engcono ekushisweni kwe-vacuum ephezulu.
Isikhathi sokuthunyelwe: Meyi-07-2022