Ukushiswa kwama-Superalloys

Ukushiswa kwama-Superalloys

(1) Izici ze-brazing Ama-superalloy angahlukaniswa ngezigaba ezintathu: isisekelo se-nickel, isisekelo sensimbi kanye nesisekelo se-cobalt. Anezakhiwo ezinhle zemishini, ukumelana nokushiswa kwe-oxidation kanye nokumelana nokugqwala emazingeni okushisa aphezulu. I-alloy yesisekelo se-nickel iyona esetshenziswa kakhulu ekukhiqizeni okusebenzayo.

I-superalloy iqukethe i-Cr2O3 oxide eningi, kanti ifilimu ye-Cr2O3 oxide okunzima ukuyisusa yakhiwa phezu kobuso ngesikhathi sokushisa. Ama-superalloy e-nickel base aqukethe i-Al ne-Ti, okulula ukuyi-oxidation uma ishiswa. Ngakho-ke, ukuvimbela noma ukunciphisa uku-oxidation kwama-superalloy ngesikhathi sokushisa nokususa ifilimu ye-oxide kuyinkinga eyinhloko ngesikhathi sokushiswa. Njengoba i-borax noma i-boric acid ekugelezeni kungabangela ukugqwala kwensimbi eyisisekelo ekushiseni kwe-brazing, i-boron evele ngemva kokusabela ingangena ensimbini eyisisekelo, okuholela ekungeneni kwe-intergranular. Kuma-alloy e-nickel e-cast alloys anokuqukethwe okuphezulu kwe-Al ne-Ti, izinga le-vacuum esimweni esishisayo akufanele libe ngaphansi kuka-10-2 ~ 10-3pa ngesikhathi sokushiswa ukuze kugwenywe ukugqwala ebusweni be-alloy ngesikhathi sokushisa.

Ukuze uthole ama-alloy esisekelo se-nickel aqiniswe ngesisombululo kanye nemvula, izinga lokushisa le-brazing kufanele lihambisane nezinga lokushisa lokushisa lokwelashwa kwesisombululo ukuqinisekisa ukuncibilika okuphelele kwezinto ze-alloy. Izinga lokushisa le-brazing liphansi kakhulu, futhi izinto ze-alloy azikwazi ukuncibilika ngokuphelele; Uma izinga lokushisa le-brazing liphezulu kakhulu, okusanhlamvu kwensimbi okuyisisekelo kuzokhula, futhi izakhiwo zezinto ngeke zibuyiselwe ngisho nangemva kokwelashwa ngokushisa. Izinga lokushisa lesisombululo esiqinile lama-alloy esisekelo ahlanganisiwe liphezulu, ngokuvamile ngeke lithinte izakhiwo zezinto ngenxa yokushisa okuphezulu kakhulu kwe-brazing.

Amanye ama-superalloy e-nickel base, ikakhulukazi ama-alloy aqiniswe yimvula, anomkhuba wokuqhekeka kokucindezeleka. Ngaphambi kokushiswa kwensimbi, ukucindezeleka okwakhiwe kule nqubo kumele kususwe ngokuphelele, futhi ukucindezeleka kokushisa kufanele kuncishiswe ngesikhathi sokushiswa kwensimbi.

(2) I-alloy yesisekelo se-nickel yezinto zokubumba ingafakwa i-brazing ngesisekelo sesiliva, ithusi elimsulwa, isisekelo se-nickel kanye ne-solder esebenzayo. Uma izinga lokushisa lokusebenza lejoyinti lingekho phezulu, izinto ezisekelwe esiliva zingasetshenziswa. Kunezinhlobo eziningi ze-solders zesiliva. Ukuze kuncishiswe ukucindezeleka kwangaphakathi ngesikhathi sokushisa kwe-brazing, kungcono ukukhetha i-solder enokushisa okuphansi kokuncibilika. I-Fb101 flux ingasetshenziswa i-brazing ngensimbi yesiliva yokugcwalisa isisekelo. I-Fb102 flux isetshenziselwa i-brazing precipitation eqiniswe i-superalloy enokuqukethwe okuphezulu kwe-aluminium, futhi i-10% ~ 20% ye-sodium silicate noma i-aluminium flux (njenge-fb201) yengezwa. Lapho izinga lokushisa le-brazing lidlula u-900 ℃, i-fb105 flux kufanele ikhethwe.

Uma ufaka i-brazing endaweni evalekile noma evikelayo, ithusi elimsulwa lingasetshenziswa njengensimbi yokugcwalisa i-brazing. Izinga lokushisa le-brazing lingu-1100 ~ 1150 ℃, futhi ijoyinti ngeke lidale ukuqhekeka kokucindezeleka, kodwa izinga lokushisa lokusebenza akufanele lidlule ku-400 ℃.

Insimbi yokugcwalisa i-brazing base brazing metal isetshenziswa kakhulu kuma-Superalloys ngenxa yokusebenza kwayo okuhle kwezinga lokushisa eliphezulu kanye nokungabi nokucindezeleka ngesikhathi sokugcwalisa i-brazing. Izinto eziyinhloko ze-alloy ku-solder yesisekelo se-nickel yi-Cr, Si, B, kanti inani elincane le-solder liqukethe ne-Fe, W, njll. Uma kuqhathaniswa ne-ni-cr-si-b, insimbi yokugcwalisa i-brazing ye-b-ni68crwb inganciphisa ukungena kwe-B phakathi kwe-granular ensimbini eyisisekelo futhi inyuse isikhathi sokushisa sokuncibilika. Iyinsimbi yokugcwalisa i-brazing yezingxenye zokusebenza ezishisa kakhulu kanye nama-turbine blades. Kodwa-ke, ukugeleza kwe-solder equkethe i-W kuba kubi kakhulu futhi igebe elihlangene kunzima ukulilawula.

Insimbi yokugcwalisa i-brazing diffusion esebenzayo ayinayo i-Si element futhi inokumelana okuhle kakhulu kwe-oxidation kanye nokumelana ne-vulcanization. Izinga lokushisa le-brazing lingakhethwa kusuka ku-1150 ℃ kuya ku-1218 ℃ ngokuya ngohlobo lwe-solder. Ngemuva kwe-brazing, i-brazed joint enezakhiwo ezifanayo nensimbi eyisisekelo ingatholakala ngemuva kokwelashwa kwe-diffusion engu-1066 ℃.

(3) I-alloy ye-nickel yenqubo ye-brazing ingathatha i-brazing esithandweni somoya esivikelayo, i-vacuum brazing kanye nokuxhumeka kwesigaba soketshezi oludlulayo. Ngaphambi kwe-brazing, indawo engaphezulu kumele isuswe amafutha bese isuswa i-oxide ngokupholisha i-sandpaper, ukupholisha amasondo e-felt, ukuklwebha i-acetone kanye nokuhlanza amakhemikhali. Lapho ukhetha amapharamitha enqubo ye-brazing, kufanele kuqashelwe ukuthi izinga lokushisa lokushisa akufanele libe phezulu kakhulu futhi isikhathi se-brazing kufanele sibe sifushane ukuze kugwenywe ukusabela kwamakhemikhali okunamandla phakathi kokushintshashintsha kanye nensimbi eyisisekelo. Ukuze kuvinjelwe insimbi eyisisekelo ekuqhekekeni, izingxenye ezibandayo ezicutshungulwayo kufanele zincishiswe ukucindezeleka ngaphambi kokupholisha, futhi ukushisa kwe-welding kufanele kufane ngangokunokwenzeka. Ngama-superalloy aqiniswe imvula, izingxenye kufanele ziphathwe ngesisombululo esiqinile kuqala, bese zipholisha ekushiseni okuphezulu kancane kunokwelashwa kokuqinisa ukuguga, bese ekugcineni ukwelashwa kokuguga.

1) Ukushiswa kwe-brazing esithandweni somoya esivikelayo Ukushiswa kwe-brazing esithandweni somoya esivikelayo kudinga ukuhlanzeka okuphezulu kwegesi yokuvikela. Kuma-superalloy ane-w (AL) kanye ne-w (TI) ngaphansi kuka-0.5%, iphuzu lamazolo kufanele libe ngaphansi kuka--54 ℃ lapho kusetshenziswa i-hydrogen noma i-argon. Lapho okuqukethwe kwe-Al ne-Ti kukhuphuka, ubuso be-alloy buyaqhubeka nokushiswa lapho bushiswa. Izinyathelo ezilandelayo kumele zithathwe; Engeza inani elincane lokushiswa (njenge-fb105) bese ususa ifilimu ye-oxide nge-flux; ungqimba oluyi-0.025 ~ 0.038mm lufakwe phezu kwezingxenye; Futha i-solder ebusweni bezinto ezizoshiswa kusengaphambili; Engeza inani elincane lokushiswa kwegesi, njenge-boron trifluoride.

2) I-vacuum brazing I-vacuum brazing isetshenziswa kabanzi ukuthola umphumela wokuvikela ongcono kanye nekhwalithi ye-brazing. Bheka ithebula 15 ukuthola izakhiwo zemishini zamajoyinti ajwayelekile e-nickel base superalloy. Kuma-superalloy ane-w (AL) kanye ne-w (TI) ngaphansi kuka-4%, kungcono ukufaka ungqimba lwe-nickel oluyi-0.01 ~ 0.015mm ebusweni, yize ukumanzisa kwe-solder kungaqinisekiswa ngaphandle kokwelashwa okukhethekile. Uma i-w (AL) kanye ne-w (TI) kudlula u-4%, ubukhulu be-nickel coating buzoba ngu-0.020.03mm. I-coating encane kakhulu ayinawo umphumela wokuvikela, futhi i-coating ebanzi kakhulu izonciphisa amandla e-joint. Izingxenye ezizoshintshwa zingafakwa ebhokisini ukuze kushiswe i-vacuum brazing. Ibhokisi kufanele ligcwaliswe nge-getter. Isibonelo, i-Zr imunca igesi ekushiseni okuphezulu, okungakha i-vacuum yendawo ebhokisini, ngaleyo ndlela kuvimbele ukushiswa kobuso be-alloy.

Ithebula 15 izakhiwo zemishini zama-Vacuum Brazed Joints ama-superalloy ajwayelekile e-nickel base

Isakhiwo esincane kanye namandla e-brazed joint ye-Superalloy kuyashintsha nge-brazing gap, kanye nokwelashwa kokusabalalisa ngemva kokufaka kuzokwandisa inani eliphezulu elivumelekile le-joint gap. Uma sibheka i-Inconel alloy njengesibonelo, i-gap ephezulu ye-Inconel joint efakwe i-b-ni82crsib ingafinyelela ku-90um ngemva kokwelashwa kokusabalalisa ku-1000 ℃ nge-1H; Kodwa-ke, kuma-joint afakwe i-b-ni71crsib, i-gap ephezulu ingaba ngu-50um ngemva kokwelashwa kokusabalalisa ku-1000 ℃ nge-1H.

3) Uxhumano lwesigaba soketshezi oluthatha isikhathi esifushane Uxhumano lwesigaba soketshezi oluthatha isikhathi esifushane lusebenzisa i-alloy ye-interlayer (cishe ubukhulu obungu-2.5 ~ 100um) lapho iphuzu lokuncibilika liphansi kunensimbi eyisisekelo njengensimbi yokugcwalisa. Ngaphansi kwengcindezi encane (0 ~ 0.007mpa) kanye nokushisa okufanele (1100 ~ 1250 ℃), izinto ze-interlayer ziqala ngokuncibilika futhi zimanzise insimbi eyisisekelo. Ngenxa yokusabalala okusheshayo kwezinto, ukuqina kwe-isothermal kwenzeka ejoyintini ukuze kwakheke ijoyinti. Le ndlela inciphisa kakhulu izidingo ezifanayo zobuso bensimbi eyisisekelo futhi inciphise ingcindezi yokushisela. Amapharamitha ayinhloko oxhumano lwesigaba soketshezi oluthatha isikhathi esifushane ukucindezela, izinga lokushisa, isikhathi sokubamba kanye nokwakheka kwe-interlayer. Faka ingcindezi encane ukugcina ubuso bokuhlangana be-weldment buxhumene kahle. Izinga lokushisa nesikhathi sokushisa kunomthelela omkhulu ekusebenzeni kwejoyinti. Uma ijoyinti lidingeka ukuthi liqine njengensimbi eyisisekelo futhi lingathinti ukusebenza kwensimbi eyisisekelo, kuzosetshenziswa amapharamitha enqubo yokuxhumanisa okushisa okuphezulu (njenge-≥ 1150 ℃) kanye nesikhathi eside (njenge-8 ~ 24h); Uma ikhwalithi yokuxhumanisa yejoyinti incishisiwe noma insimbi eyisisekelo ingakwazi ukumelana nokushisa okuphezulu, kuzosetshenziswa izinga lokushisa eliphansi (1100 ~ 1150 ℃) kanye nesikhathi esifushane (1 ~ 8h). Ingqimba ephakathi kufanele ithathe ukwakheka kwensimbi eyisisekelo exhunyiwe njengokwakheka okuyisisekelo, bese yengeza izinto ezahlukene zokupholisa, njenge-B, Si, Mn, Nb, njll. Isibonelo, ukwakheka kwe-Udimet alloy yi-ni-15cr-18.5co-4.3al-3.3ti-5mo, kanti ukwakheka kwengqimba ephakathi yokuxhumeka kwesigaba soketshezi oludlulayo yi-b-ni62.5cr15co15mo5b2.5. Zonke lezi zinto zinganciphisa izinga lokushisa lokuncibilika kwama-alloy e-Ni Cr noma e-Ni Cr Co libe liphansi kakhulu, kodwa umphumela we-B usobala kakhulu. Ngaphezu kwalokho, izinga eliphezulu lokusabalala kwe-B lingenza i-alloy ehlanganisiwe kanye nensimbi eyisisekelo ibe yi-homogeneous ngokushesha.