Txhawm rau hais txog cov txheej txheem nyuaj uas yuav tsum tau ua hauv thaj chaw xws li aerospace, hmoov casting zoo daws cov teeb meem kev sib tw hauv kev txiav txim siab, xws li shrinkage kab noj hniav, porosity, thiab compositional segregation, nrog rau ntau yam teeb meem cuam tshuam nrog vuam forgings. Tam sim no, nyob rau hauv zus tau tej cov Ti2AlNb alloys siv hmoov metallurgy, peb tsom mus rau lub kub isostatic nias (HIP) txheej txheem tsis (lub sij hawm, kub, siab), tom qab kev kho cua sov thiab kub deformation txheej txheem, thiab kev kawm ntawm lub microstructure thiab kev ua tau zoo ntawm cov hmoov alloys thiab qhov ntev ntawm tsim Cheebtsam. Peb lub tuam txhab tau npaj Ti2AlNb ua ntej-alloyed hmoov siv cov txheej txheem plasma rotating electrode (PREP) thiab tom qab ntawd tsim Ti2AlNb hmoov alloys los ntawm cov hmoov kub isostatic nias txheej txheem.
Txoj kev npaj ntawm Ti2AlNb hmoov alloy: Ti2AlNb ua ntej-alloyed hmoov nrog ib tug particle loj hauv qab no 250 μm yog loaded rau hauv ib tug cylindrical tsawg- carbon steel sheath nyob rau hauv ib qho chaw atmospheric. Tom qab compaction, qhov chaw vuam, nqus degassing, thiab sealing vuam, kub isostatic nias (HIP) tiav nyob rau hauv ib tug RD(Z)-1-850 hom kub isostatic nias rauv ntawm Steel Research Institute Haopu Technology Co., Ltd., kom tau cov hmoov metallurgy billets. Kub isostatic pressing txheej txheem: Lub cub tawg kub yog nce mus rau 1030 degree, lub siab yog siab tshaj 140 MPa, lub sij hawm tuav yog 2-4 h, thiab ces lub cub tawg yog txias. Cov txheej txheem kev kho cua sov: kev daws teeb meem kev kho cua sov yog 980℃rau 2 h, ua raws li lub tshuab cua txias, nrog lub sij hawm rau chav tsev kub tsis pub tsawg tshaj 1 h. Kev laus kev kho cua sov cov xwm txheej yog 890℃rau 4 h, ua raws li cov cua kub cua txias, nrog rau lub sij hawm mus rau chav tsev kub tsis tsawg tshaj li 1 h. Tom qab kub isostatic nias, txheej txheej thiab cov tub ntxhais raug tshem tawm los ntawm kev siv tshuab thiab tshuaj milling kom tau txais titanium alloy kaw impeller qhov chaw. Daim duab hauv qab no qhia txog kev sib koom ua ke thiab lub cev duab ntawm qhov kev sim kaw lub tes tsho impeller thiab cov tub ntxhais.
Fig. Sib dhos kev sib raug zoo thiab daim duab lub cev ntawm shrouded impeller lub tes tsho tub ntxhais.
Tensile zog tau sim ntawm 650℃siv lub tshuab CMT5305 hluav taws xob universal kuaj, raws li GB/T 228.2-2015 "Cov ntaub ntawv hlau, tensile xeem-Part 2: Kev ntsuas kub siab"; creep lub neej raug kuaj ntawm 650℃/ 360 MPa siv RD-100 micro- tswj hluav taws xob creep tshuab kuaj, raws li GB/T 2039-2012 "Cov ntaub ntawv hlau, uniaxial tensile creep test method"; cov qauv qhov ntev rau ob qho tib si tensile thiab creep test yog 5 hli inch thiab 25 mm nyob rau hauv gauge ntev, nrog tsawg kawg yog ob parallel specimens. Cov qauv Ti2AlNb hmoov alloy, tom qab mounting thiab polishing, tau etched nrog Kroll reagent (3% HF + 6% HNO3 + 91% H2O, ntim feem), thiab SEM cov duab tau txais los ntawm TESCAN MIRA4 teb emission scanning electron microscope. Kev tshuaj xyuas EBSD tau ua tiav ntawm Thermo Quattro S-hom SEM nruab nrog lub tshuab hluav taws xob backscatter diffraction (EBSD), thiab cov ntaub ntawv ua software yog HKL Channel 5. Lub porosity ntawm kub isostatically nias Ti2AlNb alloy yog tus cwj pwm siv VersaXRM-500 X-ray microcomputed tomography (Microcomputed tomography). Qhov tsom xam ntawm cov hmoov compact yog kwv yees li Φ1.9 hli × 2.2 hli.
Nyob rau hauv fabrication ntawm hmoov metallurgy Cheebtsam, tus tsim ntawm lub encapsulation qauv yog ib qho tseem ceeb heev. Ib qho tsim nyog tsim qauv tsim qauv yuav tsum tau ua kom ntseeg tau tias txhua qhov ntawm cov hmoov sib sau ua ke yog qhov ntom ntom thiab ua tiav nyob ze -net- cov qauv tsim. Raws li lub thawv rau kub isostatic nias (HIP) ntawm cov hmoov metallurgy alloys, lub encapsulation ncaj qha cuam tshuam rau metallurgical zoo thiab seem seem ntawm cov khoom tiav. Hauv kev xyaum, kev hloov pauv ntawm cov txheej txheem tsis sib xws thaum lub sij hawm HIP densification tuaj yeem ua rau muaj qhov sib txawv ntawm cov txheej txheem densification. Tshwj xeeb tshaj yog thaum fabricating loj, complex Cheebtsam, lub encapsulation / pwm qauv yog feem ntau kuj complex, thiab qhov sib txawv nyob rau hauv densification txheej txheem los ntawm cov nto mus rau sab hauv ntawm cov hmoov compact yog ntau pronounced, txawm exhibiting ib phenomenon ntawm "non-uniform densification." This phenomenon leads to inconsistent densification levels and shrinkage deformation in different parts of the component, thus affecting the component's mechanical properties. Siv EIGA hmoov, ntau hom Ti2AlNb hmoov metallurgy Cheebtsam tau ua tiav nyob rau hauv HIP tsoom fwv ntawm 1030℃/ 140 MPa / 3 h. Kev ntsuam xyuas pom tau tias qhov sib txawv ntawm qhov sib txawv ntawm cov khoom tseem ceeb yog tsawg dua 2%, thiab qhov zoo ntawm qhov chaw zoo dua li cov hlau cam khwb cia. Los ntawm kev siv lub ntsiab lus tseem ceeb- pab tsim qauv encapsulation, cov txheej txheem densification yuav zoo ib yam nyob rau hauv tag nrho cov txheej txheem densification, kom tsis txhob muaj qhov tshwm sim ntawm "non-uniform densification" thiab pab ua kom qhov sib xws ntawm tag nrho cov kev ua tau zoo ntawm cov khoom.
1) Piv nrog rau PREP txoj kev, Ti2AlNb ua ntej-alloyed hmoov npaj los ntawm EIGA txoj kev muaj ib tug dav particle loj tis, ib tug me me ntawm satellite spheres, thiab ntau dua kais ceev.
(2) Piv nrog Ti2AlNb alloy tsim los ntawm kub isostatic nias ntawm PREP hmoov, lub siab - kub lub zog thiab creep lub neej ntawm cov alloy sib xws rau EIGA hmoov yog me ntsis txo, tab sis lub elongation yog zoo dua vim lub siab uniformity ntawm lub microstructure. Hauv cov txheej txheem kev npaj ua ke, cov txiaj ntsig zoo kawg nkaus simulation qhia tau tias Ti2AlNb impeller npaj los ntawm EIGA hmoov muaj qhov me me thiab yog qhov tsim nyog rau kub isostatic nias ntawm cov khoom nyuaj.
(3) Siv finite element simulation los pab tsim lub encapsulation, complex Ti2AlNb hmoov metallurgy Cheebtsam tau ntse npaj siv EIGA pre-alloyed hmoov. Cov khoom muaj qhov loj me thiab qhov tseeb ntawm qhov chaw thiab tsis muaj qhov tsis xws luag ntawm metallurgy.
