01
Daim Ntawv Qhia
Lub fabrication ntawm lub teeb yuag, siab - lub zog aluminium alloys ntawm Laser Powder Bed Fusion (LPBF) tau ntev cia siab rau cov khoom kim heev alloying ntsiab -xws li scandium thiab zirconium- kom ua tiav lub zog siab; Qhov kev vam khom no tau cuam tshuam loj heev rau lawv txoj kev siv dav hauv kev lag luam. Txawm hais tias qhov sib ntxiv ntawm cov nqi qis (piv txwv li, TiB2, TiC) tuaj yeem, rau qee qhov, kho cov qauv nplej thiab txhim kho lub zog, lub tswv yim ntawm kev sib koom ua ke ntawm exogenous particles feem ntau ntsib cov teeb meem xws li particle agglomeration, non{8}}uniform dispersion, thiab tsis zoo interfacial bonding, ua rau cov khoom sib xyaw ua ke thiab microstructure. Txhawm rau daws qhov teeb meem no, txoj kev tshawb fawb tam sim no nthuav tawm lub tswv yim tshiab uas ua rau pom qhov xav tau ntawm cov khoom kim. Los ntawm leveraging qhov kub thiab txias gradients thiab laser-induced recoil pressures inherent rau LPBF txheej txheem, cov kws tshawb fawb tau ua tiav cov * hauv-situ* synthesis ntawm ntom thiab uniformly dispersed MgAlB4 nanowhiskers nyob rau hauv ib tug AA2024 txhuas alloy matrix. Daim ntawv no tsom mus tshem tawm cov kab nrib pleb thiab cov porosity- yog li ua tiav yuav luag tag nrho cov ntom ntom- dhau ntawm * hauv -situ* tiam ntawm ib -dimensional nanowhiskers. Tsis tas li ntawd, los ntawm kev nqis peev ntawm qhov sib piv siab thiab muaj zog sib cuam tshuam ntawm cov pob tw no, txoj kev tshawb fawb nrhiav kev txhim kho ob qho tib si lub zog thiab ductility ntawm cov hlau, yog li tawg los ntawm qhov ntev -kev lag luam sawv ntsug- tawm ntawm kev cuam tshuam ntawm kev ua tau zoo thiab tus nqi hauv kev lag luam aluminium alloy additive manufacturing.
02
Daim Ntawv Qhia Tag Nrho
Hais txog qhov tsis xws luag hauv lub cev-xws li coarse columnar nplej, hnyav kub tawg, thiab porosity siab-feem ntau ntsib hauv kev lag luam siab-lub zog aluminium alloys fabricated ntawm Laser Powder Bed Fusion (LPBF), txoj kev tshawb no nthuav tawm txoj hauv kev tshiab rau * hauv -situs 4} alloys. Los ntawm kev sib xyaw cov kab ntawm amorphous boron hmoov rau hauv AA2024 hmoov, thiab leveraging tus ceev ceev txias thiab siab yaj-pool recoil pressures (txog 40 MPa) tus yam ntxwv ntawm cov txheej txheem LPBF, MgAlB4 nanowhiskers -muaj 5 diameters thiab ntau tshaj li ntawm 1m. 20-tau ua tiav * nyob rau hauv-situ* nyob rau hauv lub txhuas matrix. Ua raws li heterogeneous nucleation sites, cov no tsis sib xws ntawm ib qho - qhov ntev whiskers induced ib tug transformation nyob rau hauv grain morphology: los ntawm ntxhib columnar grains kaum ntawm micrometers nyob rau hauv dav rau ultrafine equiaxed nplej nrog qhov nruab nrab loj ntawm kwv yees li 1.3 mus rau 1.5 μm. Qhov kev hloov pauv no tau tshem tawm tag nrho cov kab nrib pleb, ua rau muaj qhov ntom ntom ntawm 99.991%. Hais txog lub hauv paus kev siv tshuab, lub quasi - cov qauv txuas txuas ntxiv tsim los ntawm cov hlua khi tsis yog tsuas yog ua kom yooj yim rau kev khaws cia thiab kev loj hlob ntawm cov dislocations tab sis kuj tau ua kom muaj kev cuam tshuam los ntawm kev hla cov whiskers nyob rau hauv ib qho kev taw qhia perpendicular rau lawv cov axes, yog li ntawd zoo txo cov kev ntxhov siab. Cov txiaj ntsig kev sim ua kom pom tias cov hlau ua tiav qhov kawg tensile lub zog (UTS) ntawm kwv yees li 610 MPa thiab ib qho elongation ntawm 8.0%; Tsis tas li ntawd, nws nthuav tawm qhov tshwj xeeb siab -kub thermomechanical zog nyob rau thaj tsam ntawm 150℃txog 250 degree. Txoj kev tshawb no muaj kev cog lus thiab kev daws teeb meem loj rau kev txhim kho qis - nqi, kev ua tau zoo aluminium alloys ntawm kev tsim khoom ntxiv.
03
**Visual Analysis**
Daim duab 1 qhia txog cov txheej txheem tsim khoom ntawm MgAlB4w / AA2024 kev sib xyaw thiab cov yam ntxwv meej ntawm nws qhov tsis xws luag. Txoj kev tshawb no siv peb -dimensional mechanical dispersion method kom uniformly coat amorphous boron hmoov rau saum npoo ntawm AA2024 hmoov hmoov ua ntej LPBF luam ntawv. Kev sib piv 3D scans tau los ntawm Nano-CT kom meej meej qhia tau tias sab hauv ntawm qhov tsis kho, LPBF-fabricated AA2024 alloy yog riddled nrog macroscopic tawg thiab loj pores ncua raws li kev tsim, uas ua rau ib tug defect ntim feem ntau li 4.698%. Hauv qhov sib piv, tom qab * hauv-situ* synthesis ntawm MgAlB4 nanowhiskers, cov kab nrib pleb hauv cov hlau tau raug tshem tawm tag nrho; tsuas yog ib qho tsis txaus ntseeg ntawm feeb kheej kheej qhov pores tseem nyob, yog li ua tiav qhov ze ntawm - puv ntom ntom ntawm 99.991%.
