1. Izinto Ezinkulu Ezinomthelela Ekwakhekeni Kwe-Crack
1.1 Ngesikhathi sokusakazwa kancane kancane, amanzi okupholisa afuthwa ngokuqondile endaweni ye-ingot, okudala izinga lokushisa elikhuphukayo ngaphakathi kwengot. Lokhu kubangela ukufinyela okungalingani phakathi kwezifunda ezihlukene, okubangela ukubambana kanye nokukhiqiza izingcindezi ezishisayo. Ngaphansi kwezimo ezithile zokucindezeleka, lezi zingcindezi zingaholela ekuqhekekeni kwe-ingot.
1.2 Emkhiqizweni wezimboni, ukuqhekeka kwe-ingot kuvame ukwenzeka esigabeni sokuqala sokulingisa noma kusuka njengama-microcracks asakazeka kamuva ngesikhathi sokupholisa, okungenzeka asakazeke kuyo yonke ingot. Ngaphezu kokuqhekeka, okunye ukukhubazeka okufana nokuvala okubandayo, i-warping, nokulenga kungase kwenzeke phakathi nesiteji sokuqala sokuphonsa, okwenza kube yisigaba esibucayi kuyo yonke inqubo yokuphonsa.
1.3 Ukuvumeleka kokuphola okuqondile ekuqhekekeni okushisayo kuthonywa kakhulu ukwakheka kwamakhemikhali, izengezo eziphambili zealloy, kanye nenani lezihlungi zokusanhlamvu ezisetshenzisiwe.
1.4 Ukuzwela okushisayo kokuqhekeka kwama-alloys kubangelwa ikakhulukazi ukucindezeleka kwangaphakathi okwenza ukwakheka kwama-voids kanye nokuqhekeka. Ukwakheka nokusabalalisa kwazo kunqunywa izakhi ze-alloying, ikhwalithi ye-metallurgical encibilikayo, kanye nemingcele yokusakazwa eqhubekayo. Ngokukhethekile, ama-ingos anosayizi omkhulu we-7xxx series alloys aluminium ajwayele kakhulu ukuqhekeka okushisayo ngenxa yezakhi eziningi ze-alloying, ububanzi bokuqiniswa okubanzi, ukucindezela kokusakazwa okuphezulu, ukuhlukaniswa kwe-oxidation yezakhi ze-alloy, ikhwalithi ye-metallurgical engalungile, kanye nokwakheka okuphansi ekamelweni lokushisa.
1.5 Ucwaningo lubonise ukuthi izinkambu kazibuthe kagesi nezinto ze-alloying (okuhlanganisa izihlungi zokusanhlamvu, izakhi ezinkulu ze-alloying, nama-trace elements) kuthinta kakhulu i-microstructure kanye nokuba sengozini kokuqhekeka okushisayo kwama-alloys ochungechunge oluyi-7xxx.
1.6 Ukwengeza, ngenxa yokwakheka okuyinkimbinkimbi kwe-7050 aluminium alloy kanye nokuba khona kwezakhi ezixutshwe kalula, inyibiliki ivame ukumunca i-hydrogen eyengeziwe. Lokhu, kuhlanganiswe ne-oxide inclusions, kuholela ekubambisaneni kwegesi kanye ne-inclusions, okwenza kube nokuqukethwe okuphezulu kwe-hydrogen ekuncibilikeni. Okuqukethwe kwe-hydrogen sekuyinto ebalulekile ethinta imiphumela yokuhlolwa, ukuziphatha kokuphuka, nokusebenza kokukhathala kwezinto ezicutshungulwayo ze-ingot. Ngakho-ke, ngokusekelwe kumshini wokuba khona kwe-hydrogen ekuncibilikeni, kuyadingeka ukusebenzisa imidiya ye-adsorption kanye nemishini yokuhlunga ukuze kukhishwe i-hydrogen nezinye izinto ezifakiwe ekuncibilikeni ukuze kutholakale ukuncibilika kwe-alloy ehlanzekile kakhulu.
2. Izimbangela Ezincane Kakhulu Zokwakhiwa Kwe-Crack
2.1 Ukuqhekeka okushisayo kwe-Ingot kunqunywa ngokuyinhloko izinga lokuncipha kokuqina, izinga lokudla, kanye nosayizi obalulekile wendawo ye-mushy. Uma ubukhulu bendawo ye-mushy budlula umkhawulo obalulekile, ukuqhekeka okushisayo kuzokwenzeka.
2.2 Ngokuvamile, inqubo yokuqiniswa kwama-alloys ingahlukaniswa ngezigaba eziningana: ukuphakela ngobuningi, ukuphakela nge-interdendritic, ukuhlukaniswa kwe-dendrite, kanye nokuhlanganisa i-dendrite.
2.3 Ngesikhathi sesigaba sokuhlukaniswa kwe-dendrite, izingalo ze-dendrite ziba zisondelene kakhulu futhi ukugeleza koketshezi kukhawulelwe ukushuba kwendawo. I-permeability ye-mushy zone iyancipha, futhi ukuqina okwanele kokuqina nokucindezeleka okushisayo kungase kuholele ku-microporosity noma ngisho nemifantu eshisayo.
2.4 Esigabeni sokuhlanganisa i-dendrite, kusala uketshezi oluncane kuphela ezindaweni ezihlangana kathathu. Kuleli qophelo, i-semi-solid material inamandla amakhulu kanye ne-plasticity, futhi i-solid-state creep ukuphela kwendlela yokuvala ukuqina kokuqina nokucindezeleka okushisayo. Lezi zigaba ezimbili yizona ezingase zenze ama-shrinkage voids noma imifantu eshisayo.
3. Ukulungiswa kwezingongo ze-Slab ezisezingeni eliphezulu ezisuselwe ku-Crack Formation Mechanisms
3.1 Ama-slab ingots anosayizi omkhulu ngokuvamile abonisa ukuqhekeka kwendawo, ukuvuleka kwangaphakathi, nokufaka, okuba nomthelela omkhulu ekuziphatheni komshini ngesikhathi sokuqina kwe-alloy.
3.2 Izici zomshini zengxubevange ngesikhathi sokuqina zincike kakhulu ezicini zesakhiwo sangaphakathi, okuhlanganisa usayizi wokusanhlamvu, okuqukethwe kwe-hydrogen, namazinga okufakwa.
3.3 Kuma-alloys e-aluminium anezakhiwo ze-dendritic, isikhala sezingalo se-dendrite yesibili (i-SDAS) sithinta ngokuphawulekayo kokubili izici zemishini kanye nenqubo yokuqinisa. I-Finer SDAS iholela ekwakhekeni kwe-porosity yangaphambili kanye nezingxenye eziphakeme ze-porosity, ukunciphisa ingcindezi ebalulekile yokuqhekeka okushisayo.
3.4 Ukukhubazeka okufana ne-interdendritic shrinkage voids kanye ne-inclusions kwenza buthaka kakhulu ukuqina kwamathambo aqinile futhi kunciphisa kakhulu ukucindezeleka okubalulekile okudingekayo ekuqhekekeni okushisayo.
3.5 I-Grain morphology ingesinye isici esibalulekile se-microstructural esithonya ukuziphatha kokuqhekeka okushisayo. Lapho izinhlamvu zishintsha zisuka kuma-columnar dendrites ziye kuzinhlamvu ze-globular equiaxed, ingxubevange ibonisa izinga lokushisa eliphansi lokuqina kanye nokufinyeleleka koketshezi kwe-interdendritic okuthuthukisiwe, okucindezela ukukhula kwezimbotshana. Ukwengeza, okusanhlamvu okucolekile kungakwazi ukuthwala ukukhahlamezeka okukhulu kanye namazinga obunzima futhi kuveze izindlela eziyinkimbinkimbi zokusabalalisa imifantu, ngaleyo ndlela kunciphise ukuthambekela kokuqhekeka okushisayo.
3.6 Ekukhiqizeni okusebenzayo, ukuthuthukisa amasu okubamba okuncibilika kanye nokuphonsa-njengokulawula ngokuqinile ukufakwa kanye nokuqukethwe kwe-hydrogen, kanye nesakhiwo sokusanhlamvu-kungathuthukisa ukumelana kwangaphakathi kwama-slab ingots ekuqhekekeni okushisayo. Kuhlanganiswe nokwakhiwa kwamathuluzi athuthukisiwe nezindlela zokucubungula, lezi zinyathelo zingaholela ekukhiqizweni kwezingots ze-slab ezinesivuno esikhulu, ezinkulu, nezisezingeni eliphezulu.
4. Ukucwengwa Okusanhlamvu kwe-Ingot
I-7050 aluminium alloy ngokuyinhloko isebenzisa izinhlobo ezimbili zezihlungi zokusanhlamvu: i-Al-5Ti-1B ne-Al-3Ti-0.15C. Izifundo zokuqhathanisa ekusetshenzisweni kwe-inthanethi kwalaba bacwengisisi zibonisa:
4.1 Ama-Ingots acwengisiswe nge-Al-5Ti-1B abonisa amasayizi amancane kakhulu okusanhlamvu kanye noshintsho olufanayo ukusuka onqenqemeni lwe-ingot ukuya maphakathi. Isendlalelo esimahhadla sincane, futhi umphumela wokucwenga okusanhlamvu usuwonke unamandla kuyo yonke ingot.
4.2 Uma kusetshenziswa izinto zokusetshenziswa ezicwengisiswe ngaphambilini nge-Al-3Ti-0.15C, umphumela wokucwenga okusanhlamvu we-Al-5Ti-1B uyancipha. Ngaphezu kwalokho, ukukhulisa isengezo se-Al-Ti-B ngaphezu kwephuzu elithile akukhulisi ngokulinganayo ukuhluzwa okusanhlamvu. Ngakho-ke, ukungezwa kwe-Al-Ti-B kufanele kukhawulelwe kungabi ngaphezu kwama-2 kg/t.
4.3 Ama-Ingots acwengisiswe nge-Al-3Ti-0.15C aqukethe ikakhulukazi izinhlamvu ezicolekile, eziyi-globular equiaxed. Usayizi wokusanhlamvu ufana ngokuqhathaniswa nobubanzi be-slab. Ukwengezwa kwe-3–4 kg/t kwe-Al-3Ti-0.15C kusebenza kahle ekusimamiseni ikhwalithi yomkhiqizo.
4.4 Ngokuphawulekayo, lapho i-Al-5Ti-1B isetshenziswa ku-7050 alloy, izinhlayiya ze-TiB₂ zivame ukuhlukana ziye kufilimu ye-oxide endaweni ye-ingot ngaphansi kwezimo zokupholisa ngokushesha, zakhe amaqoqo aholela ekwakhekeni kwe-slag. Ngesikhathi sokuqiniswa kwe-ingot, lawa maqoqo ashwabana ngaphakathi ukuze akhe imigoqo efana ne-groove, eshintsha ukushuba kwendawo kokuncibilika. Lokhu kwandisa i-viscosity encibilikayo futhi kunciphisa uketshezi, okubuye kukhuthaze ukwakheka kokuqhekeka phansi kwesikhunta kanye namakhona obuso obubanzi nobuncane bengot. Lokhu kuphakamisa kakhulu ukuthambekela kokuqhekeka futhi kuthinte kabi isivuno se-ingot.
4.5 Uma kucatshangelwa indlela yokwenza ingxubevange engu-7050, ukwakheka okusanhlamvu kweziyingo ezifanayo zasekhaya nezamazwe ngamazwe, kanye nekhwalithi yemikhiqizo yokugcina ecutshunguliwe, i-Al-3Ti-0.15C ikhethwa njengesicwengisisi sokusanhlamvu esiku-inthanethi ukuze kukhishwe ingxubevange engu-7050—ngaphandle kwalapho izimo ezithile zidinga okuhlukile.
5. Ukuziphatha Kokucwengwa Okusanhlamvu kwe-Al-3Ti-0.15C
5.1 Uma isicwengisisi sokusanhlamvu sengezwa ku-720 °C, izinhlamvu ziqukethe ikakhulukazi izakhiwo ezilinganayo ezinezakhiwo ezingaphansi futhi zingosayizi omuhle kakhulu.
5.2 Uma ukuncibilika kubanjwe isikhathi eside kakhulu ngemva kokwengeza isicwengisisi (isb., ngaphezu kwemizuzu eyi-10), ukukhula kwe-dendritic emahhadla kuyabusa, okuholela ekukhuleni kwezinhlamvu.
5.3 Uma inani elingeziwe lesicwengi sokusanhlamvu lingu-0.010% ukuya ku-0.015%, okusanhlamvu okulinganayo kuyafinyelelwa.
5.4 Ngokusekelwe kunqubo yezimboni ye-7050 alloy, izimo ezilungile zokucwenga okusanhlamvu yilezi: izinga lokushisa elingeziwe elizungeze i-720 °C, isikhathi kusukela ekungezeni kuya ekuqinisweni kokugcina okulawulwa phakathi kwemizuzu engu-20, kanye nenani lokuhlanza cishe ku-0.01-0.015% (3-4 kg / t ye-Al-3Ti-0.15C).
5.5 Naphezu kokuhluka kosayizi we-ingot, isikhathi esiphelele kusukela ekungezeni isicwengisisi sokusanhlamvu ngemva kokuphuma kokuncibilika, ngohlelo olusemgqeni, umkhombe, kanye nesikhunta, kuya ekuqinisweni kokugcina ngokuvamile siyimizuzu eyi-15–20.
5.6 Ezilungiselelweni zezimboni, ukukhulisa inani lesihlungi sokusanhlamvu libe ngaphezu kokuqukethwe kwe-Ti engu-0.01% akuthuthukisi kakhulu ukuhluzwa okusanhlamvu. Esikhundleni salokho, ukwengeza ngokweqile kuholela ekunothisweni kwe-Ti no-C, okwandisa amathuba okuba nokukhubazeka kwezinto ezibonakalayo.
5.7 Ukuhlola ezindaweni ezihlukene—i-degas inlet, i-degas outlet, ne-casting trough—ibonisa umehluko omncane ngosayizi wokusanhlamvu. Kodwa-ke, ukwengeza umcwengisisi ngqo emgodini wokuphonsa ngaphandle kokuhlunga kwandisa ingozi yokukhubazeka ngesikhathi sokuhlolwa kwe-ultrasonic kwezinto ezicutshungulwayo.
5.8 Ukuqinisekisa ukuhluzwa okulinganayo okusanhlamvu nokuvimbela ukunqwabelana komcwengisisi, isicwengisisi sokusanhlamvu kufanele sengezwe endaweni yokungena yesistimu yokukhipha umoya.
Isikhathi sokuthumela: Jul-16-2025
