Gr9 (Ti-3Al-}2.5V) titanium alloy yog qis-aluminium sib npaug ze ntawm- hom titanium alloy tau los ntawm kev ua kom zoo dua ntawm TC4 alloy. Nws muaj cov khoom zoo heev thiab kub tsis tshua muaj zog, tiv thaiv corrosion, thiab txias thiab kub ua haujlwm plasticity, thaum tseem muaj qhov ruaj khov thiab txhim khu kev qha formability thiab weldability. Nws yog cov khoom tseem ceeb rau siab -kawg lub teeb yuag tubing. Vim nws txoj kev ua tau zoo, Gr9 titanium alloy tubing yog dav siv nyob rau hauv cov cheeb tsam tseem ceeb xws li hydraulic roj kab rau aero-engines, high-end kev ua si cov khoom, roj drilling casing, thiab tshav kub exchanges pipelines, uas tsis tshua muaj siab txheej txheem yuav tsum tau muab tso rau ntawm cov khoom uniformity, microstructure stability, thiab sib sau ua ke.
Thaum lub sij hawm txias dov ntau lawm ntawm ib pawg ntawm Gr9 titanium alloy raj, loj - cheeb tsam longitudinal penetrating tawg tshwm sim thaum cov hlab tau thinned los ntawm Φ70mm × 8mm mus rau Φ55mm × 6mm. Cov kab nrib pleb tau nyob hauv cheeb tsam raws li txoj kab ntev ntawm lub raj lub cev, tsis muaj qhov pom tseeb khawb, cuam tshuam, lossis lwm yam kev puas tsuaj sab nraud ntawm lub raj nplaim. Cov kab nrib pleb kiag li nkag mus rau hauv lub raj phab ntsa, ncaj qha ua rau 60% seem ntawm cov hlab no, ua rau muaj kev cuam tshuam loj heev rau kev nce qib thiab cov khoom tiav tiav. Txhawm rau txheeb xyuas lub hauv paus ua rau qhov tsis xws luag thiab daws qhov teeb meem tawg tawg, txoj kev tshawb no tau ua cov kev sim ua haujlwm nrog rau kev tsom xam cov khoom, kev soj ntsuam metallographic, fracture morphology tsom xam, thiab kev sib piv microhardness kom sib sib zog nqus ntsuas qhov txias dov cracking mechanism ntawm Gr9 raj thiab tsim cov txheej txheem optimization kev daws teeb meem.
Hauv qhov kev sim no, ntau cov qauv kuaj tau sau los ntawm ob qho tib si tawg thiab tsis zoo ntawm cov yeeb nkab. Cov tshuaj muaj pes tsawg leeg tau txheeb xyuas siv ICP tag nrho -spectrum ncaj qha- nyeem spectrometer thiab TC-600 oxygen thiab nitrogen analyzer. Ib txhij, cov qauv longitudinal thiab transverse metallographic qauv tau npaj, thiab metallographic etching tau ua los ntawm hydrofluoric acid, nitric acid, thiab dej-raws li etchant. Qhov sib txawv ntawm cov qauv matrix tau pom los ntawm kev siv lub tshuab kho qhov muag. Lub microstructure ntawm lub pob tawg tawg tau pom siv lub tshuab ntsuas hluav taws xob ntsuas hluav taws xob, thiab kev ntsuas qhov sib piv sib piv ntawm ntau qhov nyuaj tau ua los ntawm ob hom qauv siv lub microhardness tester los txheeb xyuas qhov tseem ceeb ntawm qhov tsis xws luag.
Kev txheeb xyuas qhov sib xyaw tau pom qhov txawv txav hauv cov qauv tawg, nrog cov ntsiab lus hlau ntau dhau thiab cov ntsiab lus oxygen mus txog qhov txwv siab tshaj ntawm tus qauv, ua rau muaj kev hloov pauv ntawm cov khoom siv. Metallographic tsom xam pom tias qhov chaw tsis zoo ntawm cov yeeb nkab tau nthuav tawm cov qauv zoo ib yam thiab ruaj khov equiaxed qauv nrog kev npaj cov nplej tsis tu ncua thiab zoo microstructure sib xws; Txawm li cas los xij, cov cheeb tsam tawg tau pom qhov txawv txav ntawm -theem nyob rau hauv txoj kev transverse thiab coarser nplej nyob rau hauv longitudinal kev taw qhia, qhia ib tug qauv ntawm Widmanstätten qauv transformation thiab loj heev deteriorated microstructure uniformity.
Kev soj ntsuam microscopic ntawm cov pob txha tawg tau lees paub tias cov yeeb nkab tawg yog ib qho kev sib tshuam ntawm cov pob txha tawg, tsis muaj cov yam ntxwv ntawm cov yas deformation, qhia txog cov txheej txheem -induced cracking los ntawm sab hauv microstructure inhomogeneity. Kev sim hardness ntxiv rau qhov tsis xws luag, qhia tias qhov nruab nrab Vickers hardness nyob rau hauv qhov chaw tawg yog 15% siab dua li ntawm cov matrix ib txwm, tsim cov cheeb tsam hardened hauv cheeb tsam thiab ua rau tsis sib xws rau dov deformation hauv cov yeeb nkab.
Kev soj ntsuam ntawm cov ntaub ntawv tshawb fawb tau nthuav tawm lub hauv paus ua rau cov kab tawg hauv cov kav dej: Thaum lub sij hawm Gr9 alloy smelting thiab batching theem, hlau ntsia hlau tau siv los ua tus neeg sawv cev doping rau alloying ntsiab. Txawm li cas los xij, cov ntsia hlau hlau tsis tuaj yeem sib cais thaum sib tov, ua rau cov hlau tsis sib xws ntawm cov khoom siv hluav taws xob. Qhov no thaum kawg tau ua rau thaj chaw hlau cais tsis xws luag hauv lub ingot. Cov cheeb tsam sib cais no tau nce cov khoom hardness thiab deformation tsis kam, ua rau hauv zos hardened blocks. Thaum lub sij hawm tom qab txias dov thiab siab yas deformation, cov cheeb tsam hardened tsis phim lub peev xwm deformation ntawm ib txwm matrix, ua rau muaj kev ntxhov siab concentration uas tsis tuaj yeem tso tawm tsis sib xws. Qhov no thaum kawg ua rau brittle cracking raws lis ciam teb, tsim longitudinal penetrating tawg.
Txhawm rau daws qhov laj thawj ntawm cov txheej txheem tsis xws luag, cov txheej txheem kev hloov kho tau raug siv los ntawm qhov kawg ntawm kev tsim khoom. Lub alloy batching system tau optimized, tshem tawm ncaj qha ntxiv ntawm hlau rau tes thiab hloov nws nrog TiFe thiab VAlFe master alloys kom ua tau zoo sib xws thiab ruaj khov smelting ntawm alloying ntsiab. Tom qab cov txheej txheem optimization thiab batch dov ntau lawm pov thawj, Gr9 titanium alloy tubes tsis pom qhov tsis xws luag xws li longitudinal cracking thiab localized brittle puas. Lub raj microstructure tau zoo ib yam, qhov ntev yog qhov ruaj khov, thiab cov qauv tsim nyog tau txais txiaj ntsig zoo dua qub, ua kom tiav qhov tseeb ntawm qhov tsis xws luag ua rau kev tsom xam thiab kev ua tau zoo ntawm cov txheej txheem rectification.
Txoj kev tshawb no ntawm cov txheej txheem txias rolling cracking ntawm Gr9 raj tau qhia meej txog qhov kev tuag ntawm cov hlau tsis sib xws thiab cov khoom sib cais ntawm kev tsim cov titanium alloy raj zoo. Nyob rau hauv kev tsim cov precision titanium alloy raj, lub uniformity ntawm smelting batching, tswj ntawm impurity ntsiab, thiab microstructure stability yog lub hauv paus tseem ceeb ntawm kev tswj qhov zoo ntawm txias dov txoj kev. Los ntawm kev ua kom zoo ntawm cov txheej txheem nruab nrab ntawm cov hlau nplaum, qhov tsis xws li cov khoom sib cais, qhov txawv txav ntawm microstructure, thiab qhov tsis sib xws tuaj yeem raug zam los ntawm qhov chaw, daws qhov teeb meem ntawm nkig tawg hauv txias dov ntawm Gr9 raj.
Qhov kev tshawb fawb no muab kev txhawb nqa tseem ceeb rau tus qauv, loj - nplai, thiab siab - zoo dov zus tau tej cov Gr9 titanium alloy raj, zoo txhim kho cov txheej txheem tswj system rau titanium alloy smelting batching thiab yas forming, thiab muaj ib tug tseem ceeb engineering daim ntawv thov nqi rau kev txhim kho qhov zoo thiab efficiency ntawm precision titanium raj, siv nyob rau hauv ib tug chemical 3.