1. Imiba yeMacroscopic eFaka iNgxaki ekuBumbeni kweCrack
1.1 Ngexesha lokusalwa okungapheliyo, amanzi okupholisa atshizwa ngokuthe ngqo kumphezulu we-ingot, edala i-gradient yobushushu ngaphakathi kwingot. Oku kukhokelela ekuncipheni okungalinganiyo phakathi kwemimandla eyahlukeneyo, kubangele ukuzibamba kunye nokuvelisa uxinzelelo lobushushu. Ngaphantsi kwemimandla ethile yoxinzelelo, olu xinzelelo lunokukhokelela ekuqhekekeni kwe-ingot.
1.2 Kwimveliso yemizi-mveliso, ukuqhekeka kwe-ingot kaninzi kwenzeka kwinqanaba lokuqala lokuphosa okanye kuvela njenge-microcracks ethi kamva isasaze ngexesha lokupholisa, enokuthi isasazeke kuyo yonke i-ingot. Ukongeza kokuqhekeka, ezinye iziphene ezifana nokuvalwa okubandayo, ukugoba, kunye nokuxhoma nazo zinokuthi zenzeke ngexesha lokuqala lokuphosa, okwenza kube yinqanaba elibalulekileyo kuyo yonke inkqubo yokuphosa.
1.3 Ukuchaphazeleka kokuphoswa kwe-chill casting ekuqhekekeni okushushu kuchaphazeleka kakhulu kukwakheka kweekhemikhali, izongezo ze-master alloy, kunye nobuninzi bezisulu zengqolowa ezisetyenzisiweyo.
1.4 I-sensitivity eshushu yokuqhekeka kwee-alloys ikakhulu ngenxa yoxinzelelo lwangaphakathi olubangela ukubunjwa kwe-voids kunye nokuqhekeka. Ukubunjwa kunye nokuhanjiswa kwazo kugqitywa ngama-alloying elements, ukunyibilika kwekhwalithi ye-metallurgical, kunye neeparitha zokuphosa ezingapheliyo. Ngokukodwa, ii-ingots ezinkulu ze-7xxx ze-aluminium alloys zithandwa kakhulu kukuqhekeka okushushu ngenxa yezinto ezininzi ze-alloying, uluhlu olubanzi lokuqiniswa, uxinzelelo oluphezulu lokuphosa, ulwahlulo lwe-oxidation yezinto ze-alloy, umgangatho ombi we-metallurgical, kunye nokwakheka okuphantsi kweqondo lokushisa.
1.5 Uphononongo lubonise ukuba amasimi e-electromagnetic kunye ne-alloying element (kubandakanywa izisulungesi zengqolowa, izinto eziphambili ze-alloying, kunye ne-trace elements) zichaphazela kakhulu ubume be-microstructure kunye nokutshisa okutshisa ukukrazuka kwe-semi-continuous cast 7xxx series alloys.
1.6 Ukongezelela, ngenxa yokubunjwa okuyinkimbinkimbi kwe-7050 i-aluminium alloy kunye nobukho bezinto ezixutywe ngokulula, i-melt idla ngokuthatha i-hydrogen eninzi. Oku, kudibene ne-oxide inclusions, kukhokelela ekubambisaneni kwegesi kunye nokubandakanywa, okubangelwa umxholo ophezulu we-hydrogen kwi-melt. Umxholo we-Hydrogen uye waba yinto ephambili echaphazela iziphumo zokuhlolwa, ukuziphatha kokuphuka, kunye nokusebenza kokukhathala kwezixhobo ze-ingot ezicutshungulwayo. Ngoko ke, ngokusekelwe kwindlela yobukho be-hydrogen kwi-melt, kuyimfuneko ukusebenzisa i-adsorption media kunye nezixhobo zokucoca i-filtration ukususa i-hydrogen kunye nezinye izinto ezifakwe kwi-melt ukuze ufumane i-alloy ehlanjululwe kakhulu.
2. IMicroscopic oonobangela bokwenziwa kweCrack
2.1 I-Ingot hot cracking inqunywe ngokuyinhloko ngumlinganiselo wokunciphisa ukuqina, izinga lokutya, kunye nobukhulu obubalulekileyo bommandla we-mushy. Ukuba ubungakanani bommandla we-mushy budlula umda obalulekileyo, ukuqhekeka okushushu kuya kwenzeka.
2.2 Ngokubanzi, inkqubo yokuqina kwee-alloys inokwahlulwa ibe ngamanqanaba ahlukeneyo: ukondla ngobuninzi, ukondla nge-interdendritic, ukwahlula i-dendrite, kunye ne-dendrite bridging.
2.3 Ngexesha lokwahlula i-dendrite, iingalo ze-dendrite ziba zipakishwe ngokusondeleyo kwaye ukuhamba kolwelo kuthintelwe kukuxinana komphezulu. I-permeability ye-mushy zone iyancitshiswa, kwaye ukuqina okwaneleyo kokuqina kunye noxinzelelo lwe-thermal kunokukhokelela kwi-microporosity okanye nakwiintanda ezishushu.
2.4 Kwinqanaba le-dendrite bridging stage, kuphela ulwelo oluncinane olushiyekileyo kwi-triple junctions. Okwangoku, i-semi-solid imathiriyeli inamandla amakhulu kunye neplastiki, kwaye i-slid-state creep kuphela kwendlela yokubuyisela ukuqina kokuqina kunye noxinzelelo lwe-thermal. Ezi zigaba zibini zezona zinokwenzeka ukuba zenze i-shrinkage voids okanye iintanda ezishushu.
3. Ukulungiswa kweeIngothi zeSlab ezikwiMgangatho oPhezulu eziSekwe kwiiNdlela zokuCwangcisa iiCrack
I-3.1 Ii-slab ingots ezinkulu zihlala zibonisa ukuqhekeka komhlaba, i-porosity yangaphakathi, kunye ne-inclusions, echaphazela kakhulu ukuziphatha komatshini ngexesha lokuqiniswa kwe-alloy.
3.2 Iimpawu zomatshini we-alloy ngexesha lokuqiniswa ngokubanzi zixhomekeke kwiimpawu zesakhiwo sangaphakathi, kubandakanywa ubungakanani bengqolowa, umxholo we-hydrogen, kunye namanqanaba okufakwa.
3.3 Kwii-alloys ze-aluminium ezinezakhiwo ze-dendritic, i-dendrite arm spacing (SDAS) ichaphazela kakhulu iipropati zombini kunye nenkqubo yokuqinisa. I-Finer SDAS ikhokelela ekwenziweni kwe-porosity kwangaphambili kunye namaqhezu aphezulu e-porosity, ukunciphisa uxinzelelo olubalulekileyo lokuqhekeka okushushu.
3.4 Iziphene ezifana ne-interdendritic shrinkage voids kunye ne-inclusions zenza buthathaka kakhulu ukuqina kwe-skeleton eqinile kunye nokunciphisa kakhulu uxinzelelo olubalulekileyo olufunekayo ekuqhekekeni okushushu.
3.5 I-Grain morphology yenye into ebalulekileyo ye-microstructural ephembelela ukuziphatha okushushu kokuqhekeka. Xa iinkozo zitshintsha ukusuka kwi-columnar dendrites ukuya kwi-globular equiaxed grains, i-alloy ibonisa ubushushu obuphantsi obuqinileyo kunye nokuphuculwa kwe-interdendritic liquid permeability, ecinezela ukukhula kwepore. Ukongeza, iinkozo ezicolekileyo zinokuthatha uxinzelelo olukhulu kunye namazinga oxinzelelo kwaye zibonise iindlela ezintsonkothileyo zokusasaza kokuqhekeka, ngaloo ndlela kuncitshiswe umkhwa wokuqhekeka okushushu.
3.6 Kwimveliso esebenzayo, ukulungelelanisa ukuphathwa kwe-melt kunye neendlela zokuphosa-ezifana nokulawula ngokungqongqo ukubandakanywa kunye nomxholo we-hydrogen, kunye nesakhiwo sengqolowa-kunokuphucula ukuchasana kwangaphakathi kwee-slab ingots kwi-slab cracking. Idityaniswe noyilo olulungisiweyo lwezixhobo kunye neendlela zokucubungula, la manyathelo angakhokelela ekuveliseni i-ingots ye-slab ephezulu, ephezulu, ephezulu.
4. Ukucokiswa kweenkozo ze-Ingot
I-7050 i-aluminiyam i-alloy ngokuyinhloko isebenzisa iindidi ezimbini zokucoca okuziinkozo: i-Al-5Ti-1B kunye ne-Al-3Ti-0.15C. Izifundo zokuthelekisa kwi-line application yaba bacokisi zibonisa:
I-4.1 Ingots esulungekisiweyo nge-Al-5Ti-1B ibonisa ubungakanani beenkozo ezincinci kakhulu kunye nokutshintshwa okufanayo ukusuka kumda we-ingot ukuya embindini. I-coarse-grained layer incinci, kwaye isiphumo sokucocwa kweenkozo ngokubanzi sinamandla kwi-ingot.
4.2 Xa kusetyenziswa imathiriyeli ekrwada ngaphambili esulungekisiweyo nge-Al-3Ti-0.15C isetyenziswa, isiphumo sokucolwa kweenkozo ze-Al-5Ti-1B siyancipha. Ngaphaya koko, ukonyusa ukongezwa kwe-Al-Ti-B ngaphaya kwendawo ethile akuphuculi ngokulinganayo ukucokiswa okuziinkozo. Ngoko ke, izongezo ze-Al-Ti-B kufuneka zikhawulelwe ukuba zingabi ngaphezu kwe-2 kg / t.
4.3 Ii-ingots ezisulungekiswe nge-Al-3Ti-0.15C zibandakanya ubukhulu becala ziinkozo ezicolekileyo, zeglobula equiaxed. Ubungakanani benkozo bufana ngokufanayo kububanzi be slab. Ukongezwa kwe-3-4 kg / t ye-Al-3Ti-0.15C iyasebenza ekuzinziseni umgangatho wemveliso.
4.4 Ngokuphawulekayo, xa i-Al-5Ti-1B isetyenziswe kwi-alloy ye-7050, iinqununu ze-TiB₂ zivame ukuhlukana ngokubhekiselele kwifilimu ye-oxide kwindawo ye-ingot phantsi kweemeko zokupholisa ngokukhawuleza, ukwenza amaqoqo akhokelela ekubunjweni kwe-slag. Ngexesha lokuqiniswa kwe-ingot, la maqela ayancipha ngaphakathi ukuze enze imigobe efana ne-groove, eguqula ukuxinezeleka komphezulu wokunyibilika. Oku kwandisa i-viscosity yokunyibilika kunye nokunciphisa i-fluidity, nto leyo ikhuthaza ukubunjwa kwe-crack kwisiseko sokungunda kunye neekona zobuso obubanzi kunye nomncinci we-ingot. Oku kuphakamisa kakhulu ukuthambekela kokuqhekeka kwaye kunefuthe elibi kwisivuno se-ingot.
I-4.5 Ukuqwalasela indlela yokwenza i-alloy ye-7050, i-grain structure yeengots ezifanayo zasekhaya nakwamanye amazwe, kunye nomgangatho weemveliso ezigqityiweyo ezigqityiweyo, i-Al-3Ti-0.15C ikhethwa njenge-in-line ye-grain refiner yokuphosa i-7050 alloy-ngaphandle kokuba iimeko ezithile zifuna enye into.
5. Ukuziphatha kokuNgconongwa kweeNkozo ze-Al-3Ti-0.15C
5.1 Xa isisulungesi sengqolowa sidityaniswe kwi-720 °C, iinkozo zibandakanya ikakhulu izakhiwo ezilinganayo kunye nezakhelo ezithile kwaye zezona zigqwesileyo ngobukhulu.
5.2 Ukuba ukunyibilika kubanjwe ixesha elide emva kokongeza isisulungesi (umz., ngaphezu kwemizuzu eli-10), ukukhula kwe-dendritic erhabaxa kukongamela, okukhokelela kwiinkozo ezirhabaxa.
5.3 Xa isixa esongezelelweyo sesisulungesi sengqolowa siyi-0.010% ukuya kwi-0.015%, iinkozo ezilinganayo ezilinganayo ziyafezekiswa.
I-5.4 Ngokusekelwe kwinkqubo yoshishino ye-7050 alloy, iimeko ezifanelekileyo zokucocwa kweenkozo zezi: ubushushu bokongeza malunga ne-720 ° C, ixesha elivela ukongezelela ukuya ekuqinisweni kokugqibela okulawulwa ngaphakathi kwemizuzu ye-20, kunye nenani lokucoca malunga ne-0.01-0.015% (3-4 kg / t ye-Al-3Ti-0.15C).
5.5 Ngaphandle kokwahluka kobukhulu be-ingot, ixesha lilonke ukusuka kokongeza isisulungesi sengqolowa emva kokuphuma kwenyibilika, nge-in-line system, umkhombe, kunye nokungunda, ukuya ekuqinisweni kokugqibela ngokuqhelekileyo yimizuzu eyi-15-20.
5.6 Kwiimeko zoshishino, ukunyusa isixa se-grain refiner ngaphaya kwe-Ti content ye-0.01% ayiphuculi kakhulu ukulungiswa kweenkozo. Endaweni yoko, ukongezwa okugqithisileyo kukhokelela ekutyebeni kwe-Ti kunye no-C, kwandisa amathuba okuba neziphene zezinto eziphathekayo.
5.7 Uvavanyo kwiindawo ezahlukeneyo—i-degas inlet, i-degas outlet, ne-casting trough—ibonisa umahluko omncinane kubungakanani beenkozo. Nangona kunjalo, ukongeza umcoci ngokuthe ngqo kwindawo yokuphosa ngaphandle kokucoca kwandisa umngcipheko weziphene ngexesha lokuhlolwa kwe-ultrasonic yezinto ezicutshungulwayo.
5.8 Ukuqinisekisa ukucocwa okufanayo kweenkozo kunye nokuthintela ukuqokelelwa komcoci, isicoci sokucolwa kweenkozo kufuneka sifakwe kwindawo yokungena kwisixokelelwano sokukhupha umoya.
Ixesha lokuposa: Jul-16-2025
