Peb siv cov ncuav qab zib los txhim kho koj qhov kev paub.Los ntawm kev txuas ntxiv mus saib lub vev xaib no, koj pom zoo rau peb siv cov ncuav qab zib.Cov ntaub ntawv ntxiv.
Additive manufacturing (AM) koom nrog tsim cov khoom 3D, ib txheej txheej ultra-nyias ib zaug, ua rau nws kim dua li kev ua ib txwm ua.Txawm li cas los xij, tsuas yog ib feem me me ntawm cov hmoov yog welded rau cov khoom thaum lub sij hawm sib dhos txheej txheem.Tus so tsis fuse, yog li lawv tuaj yeem rov siv dua.Nyob rau hauv sib piv, yog hais tias tus kwv yog tsim nyob rau hauv lub classical txoj kev, nws feem ntau yuav tsum tau milling thiab machining kom tshem tawm cov khoom.
Cov khoom ntawm cov hmoov txiav txim siab qhov tsis sib xws ntawm lub tshuab thiab yuav tsum tau coj mus rau hauv tus account hauv thawj qhov chaw.Tus nqi ntawm AM yuav tsis raug kev lag luam vim tias cov hmoov tsis muaj hmoov tsis muaj paug thiab tsis tuaj yeem rov ua dua.Powder degradation ua rau muaj ob qhov tshwm sim: kev hloov kho tshuaj ntawm cov khoom thiab kev hloov pauv ntawm cov khoom siv xws li morphology thiab particle loj tis.
Hauv thawj kis, lub luag haujlwm tseem ceeb yog los tsim cov khoom siv uas muaj cov hlau tsis huv, yog li peb yuav tsum zam kom tsis txhob muaj cov hmoov av, piv txwv li, nrog oxides lossis nitrides.Hauv qhov tshwm sim tom qab, cov kev ntsuas no cuam tshuam nrog fluidity thiab kis tau.Yog li ntawd, txhua yam kev hloov pauv ntawm cov khoom ntawm cov hmoov tuaj yeem ua rau tsis muaj kev faib tawm ntawm cov khoom.
Cov ntaub ntawv los ntawm cov ntawv tshaj tawm tsis ntev los no qhia tau hais tias classical flowmeters tsis tuaj yeem muab cov ntaub ntawv txaus txog kev faib cov hmoov hauv AM raws li cov hmoov txaj.Hais txog tus yam ntxwv ntawm cov khoom siv raw (lossis hmoov), muaj ntau txoj hauv kev ntsuas kev lag luam uas tuaj yeem ua tau raws li qhov yuav tsum tau ua.Lub xeev kev ntxhov siab thiab cov hmoov av ntws yuav tsum yog tib yam hauv kev ntsuas kev teeb tsa thiab hauv cov txheej txheem.Lub xub ntiag ntawm compressive loads yog incompatible nrog dawb nto ntws siv nyob rau hauv IM li nyob rau hauv shear testers thiab classical rheometers.
GranuTools tau tsim ib qho kev ua haujlwm rau tus cwj pwm AM hmoov.Peb lub hom phiaj tseem ceeb yog kom muab cov cuab yeej sim yooj yim nrog cov txheej txheem raug, thiab cov haujlwm no yog siv los nkag siab thiab taug qab cov kev hloov ntawm cov khoom zoo hauv cov luam ntawv.Ob peb tus qauv txhuas alloys (AlSi10Mg) raug xaiv rau lub sijhawm sib txawv ntawm qhov sib txawv thermal loads (ntawm 100 txog 200 ° C).
Thermal degradation tuaj yeem tswj tau los ntawm kev tshuaj xyuas lub peev xwm ntawm cov hmoov txhawm rau khaws cov nqi hluav taws xob.Cov hmoov tau raug tshuaj xyuas kom muaj peev xwm ntws tau (GranuDrum ntsuas), packing kinetics (GranuPack instrument) thiab electrostatic cwj pwm (GranuCharge instrument).Cohesion thiab packing kinetics ntsuas yog tsim rau kev taug qab cov hmoov zoo.
Cov hmoov uas yooj yim rau kev thov yuav qhia tau tias tsis muaj cohesion indices, thaum hmoov nrog ceev filling dynamics yuav tsim mechanical qhov chaw nrog qis porosity piv rau ntau nyuaj rau sau cov khoom.
Tom qab ob peb lub hlis ntawm kev khaws cia hauv peb lub chaw soj nstuam, peb cov hmoov txhuas txhuas nrog qhov sib txawv particle loj faib (AlSi10Mg) thiab ib qho 316L stainless hlau qauv raug xaiv, ntawm no hu ua cov qauv A, B thiab C. Cov khoom ntawm cov qauv yuav txawv ntawm lwm cov tuam txhab.TS EN ISO 13320 Cov qauv particle loj faib tau ntsuas los ntawm laser diffraction tsom xam / ISO 13320.
Vim tias lawv tswj hwm qhov tsis sib xws ntawm lub tshuab, cov khoom ntawm cov hmoov yuav tsum tau txiav txim siab ua ntej, thiab yog tias cov hmoov tsis raug suav tias yog cov kab mob tsis huv thiab tsis tuaj yeem rov ua dua, ces kev tsim khoom ntxiv tsis yog kev lag luam raws li ib qho kev cia siab.Yog li, peb qhov kev ntsuas yuav raug tshawb xyuas: hmoov ntws, ntim cov khoom siv hluav taws xob thiab electrostatics.
Spreadability muaj feem xyuam rau lub uniformity thiab "smoothness" ntawm hmoov txheej tom qab lub recoating ua hauj lwm.Qhov no yog qhov tseem ceeb heev vim tias qhov chaw du yog yooj yim dua luam tawm thiab tuaj yeem kuaj xyuas nrog GranuDrum cov cuab yeej nrog adhesion ntsuas ntsuas.
Vim tias qhov pores yog cov ntsiab lus tsis muaj zog hauv cov khoom, lawv tuaj yeem ua rau tawg.Fill dynamics yog qhov tseem ceeb thib ob vim tias cov hmoov txhaws nrawm muab cov porosity tsawg.Tus cwj pwm no yog ntsuas nrog GranuPack nrog tus nqi ntawm n1/2.
Lub xub ntiag ntawm hluav taws xob nqi nyob rau hauv cov hmoov tsim cohesive rog uas ua rau lub tsim ntawm agglomerates.GranuCharge ntsuas lub peev xwm ntawm cov hmoov ua kom muaj hluav taws xob hluav taws xob thaum sib cuag nrog cov ntaub ntawv xaiv thaum khiav.
Thaum ua tiav, GranuCharge tuaj yeem kwv yees qhov tsis zoo ntawm kev ntws, piv txwv li, thaum tsim cov txheej hauv AM.Yog li, cov kev ntsuas tau txais yog rhiab heev rau lub xeev ntawm cov nplej nto (oxidation, paug thiab roughness).Kev laus ntawm cov hmoov zoo tuaj yeem raug txheeb xyuas kom raug (± 0.5 nC).
GranuDrum yog ib qho programmed hmoov ntws ntsuas txoj hauv kev raws li lub ntsiab lus ntawm lub nruas rotating.Ib nrab ntawm cov qauv hmoov yog muaj nyob rau hauv kab rov tav lub tog raj kheej nrog pob tshab sab phab ntsa.Lub nruas rotates nyob ib ncig ntawm nws axis ntawm lub angular ceev ntawm 2 mus rau 60 rpm, thiab lub koob yees duab CCD coj cov duab (los ntawm 30 mus rau 100 dluab ntawm 1 thib ob intervals).Cov huab cua / hmoov sib cuam tshuam tau txheeb xyuas ntawm txhua daim duab uas siv cov txheej txheem ntsuas ntug.
Xam qhov nruab nrab txoj hauj lwm ntawm lub interface thiab cov oscillations nyob ib ncig ntawm qhov nruab nrab txoj hauj lwm.Rau txhua qhov kev sib hloov ceev, lub kaum sab xis ntws (lossis "lub kaum sab xis ntawm qhov rov ua haujlwm") αf yog xam los ntawm qhov nruab nrab ntawm qhov chaw sib txuas, thiab qhov sib txuas ntawm qhov sib txawv σf cuam tshuam nrog kev sib koom ua ke yog txheeb xyuas los ntawm kev hloov pauv hloov pauv.
Lub kaum sab xis ntws cuam tshuam los ntawm ntau qhov tsis sib xws: kev sib txhuam, cov duab thiab kev sib koom ua ke ntawm cov khoom (van der Waals, electrostatic thiab capillary rog).Cov hmoov cohesive ua rau cov dej tsis sib xws, thaum cov hmoov tsis khov ua rau cov dej tsis tu ncua.Tus nqi qis ntawm lub kaum sab xis ntws αf sib haum mus rau qhov dej ntws zoo.Lub dynamic adhesion Performance index ze rau xoom sib raug rau cov hmoov uas tsis yog-cohesive, yog li thaum lub adhesion ntawm cov hmoov nce, qhov adhesion Performance index nce raws li.
GranuDrum tso cai rau koj los ntsuas thawj lub kaum sab xis ntawm lub avalanche thiab lub aeration ntawm cov hmoov thaum lub sij hawm ntws, nrog rau ntsuas qhov adhesion Performance index σf thiab lub kaum sab xis αf nyob ntawm qhov kev sib hloov ceev.
Lub granupack lub ntom ntom ntom, tapping ceev thiab halausner piv ntsuas (Qhov ntom ntawm cov hmoov thiab muaj peev xwm ua kom nws qhov ntom ntom yog qhov tseem ceeb ntawm kev khaws cia, kev thauj mus los, agglomeration, thiab lwm yam. Cov txheej txheem pom zoo tau teev tseg hauv Pharmacopoeia.
Qhov kev sim yooj yim no muaj peb qhov teeb meem loj.Kev ntsuas yog nyob ntawm tus neeg teb xov tooj, thiab cov txheej txheem ntawm kev txhaws cuam tshuam rau thawj lub ntim ntawm cov hmoov.Kev ntsuas tag nrho cov ntim tuaj yeem ua rau muaj qhov yuam kev loj hauv cov txiaj ntsig.Vim qhov yooj yim ntawm qhov kev sim, peb tsis tau coj mus rau hauv tus account lub compaction dynamics ntawm qhov pib thiab zaum kawg ntsuas.
Tus cwj pwm ntawm cov hmoov pub rau hauv qhov hluav taws xob tas mus li tau txheeb xyuas siv cov cuab yeej siv tshuab.Ntsuas ntsuas qhov Hausner coefficient Hr, thawj qhov ceev ρ(0) thiab qhov ceev kawg ρ(n) tom qab n clicks.
Tus naj npawb ntawm cov kais dej feem ntau yog kho ntawm n = 500.GranuPack yog ib qho kev ntsuas qhov ntsuas siab thiab qib siab tapping raws li kev tshawb fawb tsis ntev los no.
Lwm cov indexes siv tau, tab sis lawv tsis muab ntawm no.Cov hmoov yog muab tso rau hauv ib lub raj hlau los ntawm kev nruj automated pib txheej txheem.Lub extrapolation ntawm dynamic parameter n1/2 thiab qhov siab tshaj plaws ceev ρ(∞) tau raug tshem tawm ntawm lub compaction nkhaus.
Lub teeb hollow lub tog raj kheej zaum saum cov hmoov txaj kom cov hmoov / huab cua interface theem thaum lub sij hawm compaction.Lub raj uas muaj cov qauv hmoov nce mus rau qhov siab ruaj khov ΔZ thiab ntog ywj pheej ntawm qhov siab feem ntau tsau ntawm ΔZ = 1 hli lossis ΔZ = 3 hli, uas tau ntsuas ntsuas tom qab txhua qhov kov.Xam qhov ntim V ntawm pawg los ntawm qhov siab.
Qhov ntom yog qhov piv ntawm qhov loj m rau qhov ntim ntawm cov hmoov txheej V. Qhov loj ntawm cov hmoov m yog paub, qhov ceev ρ yog siv tom qab txhua qhov cuam tshuam.
Hausner coefficient Hr muaj feem xyuam rau qhov compaction factor thiab yog soj ntsuam los ntawm qhov sib npaug Hr = ρ(500) / ρ(0), qhov twg ρ(0) yog qhov pib bulk ntom thiab ρ(500) yog cov xam ntws tom qab 500 cycles.Ceev ceev.Thaum siv txoj kev GranuPack, cov txiaj ntsig tau rov ua dua tshiab siv cov hmoov me me (feem ntau 35 ml).
Cov khoom ntawm cov hmoov thiab cov khoom ntawm cov khoom siv los ntawm cov cuab yeej tsim yog cov tsis tseem ceeb.Thaum lub sij hawm khiav, electrostatic nqi yog generated nyob rau hauv cov hmoov vim lub triboelectric nyhuv, uas yog pauv ntawm tsub kom thaum ob tug khib nyiab los rau hauv kev sib cuag.
Thaum cov hmoov ntws mus rau hauv lub cuab yeej, cov nyhuv triboelectric tshwm sim ntawm kev sib cuag ntawm cov khoom thiab ntawm kev sib cuag ntawm cov khoom thiab cov khoom siv.
Thaum sib cuag nrog cov khoom xaiv, GranuCharge cia li ntsuas tus nqi ntawm electrostatic nqi tsim nyob rau hauv cov hmoov thaum lub sij hawm ntws.Cov hmoov coj mus rau hauv lub vibrating V-tube thiab poob rau hauv lub khob Faraday txuas nrog lub tshuab hluav taws xob uas ntsuas cov nqi tau txais thaum cov hmoov txav mus rau hauv V-tube.Rau cov txiaj ntsig rov tsim dua, siv lub tshuab tig lossis vibrating los pub V-tubes nquag.
Cov nyhuv triboelectric ua rau ib qho khoom tau txais electrons ntawm nws qhov chaw thiab yog li ua tsis zoo, thaum lwm yam khoom poob electrons thiab yog li ua tau zoo.Qee cov ntaub ntawv tau txais electrons yooj yim dua li lwm tus, thiab zoo ib yam, lwm cov ntaub ntawv poob electrons yooj yim dua.
Yam khoom twg ua tsis zoo thiab qhov twg yuav zoo yog nyob ntawm tus txheeb ze propensity ntawm cov ntaub ntawv koom nrog kom tau txais lossis poob electrons.Txhawm rau sawv cev rau cov qauv no, triboelectric series qhia hauv Table 1 tau tsim.Cov ntaub ntawv uas muaj tus nqi zoo thiab lwm tus uas muaj tus nqi tsis zoo tau teev tseg, thiab cov txheej txheem cov ntaub ntawv uas tsis qhia txog kev coj tus cwj pwm yog teev nyob rau hauv nruab nrab ntawm lub rooj.
Ntawm qhov tod tes, lub rooj tsuas yog muab cov ntaub ntawv qhia txog kev hloov pauv ntawm kev coj tus cwj pwm ntawm cov khoom siv, yog li GranuCharge tau tsim los muab cov lej raug tseeb rau kev them tus cwj pwm ntawm hmoov.
Ntau qhov kev sim tau ua tiav los txheeb xyuas thermal decomposition.Cov qauv tau muab tso rau ntawm 200 ° C rau ib mus rau ob teev.Cov hmoov yog tam sim ntawd soj ntsuam nrog GranuDrum (lub npe kub).Cov hmoov tau muab tso rau hauv ib lub thawv kom txog thaum ncav cuag qhov kub thiab txias thiab tom qab ntawd tshuaj xyuas siv GranuDrum, GranuPack thiab GranuCharge (ie "txias").
Cov qauv nyoos tau txheeb xyuas siv GranuPack, GranuDrum thiab GranuCharge ntawm tib chav tsev av noo / kub (xws li 35.0 ± 1.5% RH thiab 21.0 ± 1.0 ° C kub).
Lub cohesion Performance index xam cov flowability ntawm hmoov thiab correlates nrog kev hloov nyob rau hauv txoj hauj lwm ntawm lub interface (hmoov / huab cua), uas yog tsuas yog peb hu rog (van der Waals, capillary thiab electrostatic rog).Ua ntej qhov kev sim, qhov txheeb ze huab cua humidity (RH, %) thiab kub (° C) raug kaw.Tom qab ntawd cov hmoov tau nchuav rau hauv lub nruas, thiab kev sim pib.
Peb xaus lus tias cov khoom no tsis raug rau agglomeration thaum xav txog thixotropic tsis.Interestingly, thermal stress tau hloov tus cwj pwm rheological ntawm cov hmoov ntawm cov qauv A thiab B los ntawm shear thickening rau shear thinning.Ntawm qhov tod tes, Samples C thiab SS 316L tsis cuam tshuam los ntawm qhov kub thiab txias thiab tsuas pom shear thickening.Txhua cov hmoov muaj kev sib kis tau zoo dua (piv txwv li qis cohesion Performance index) tom qab cua sov thiab txias.
Cov nyhuv kub kuj nyob ntawm thaj chaw tshwj xeeb ntawm cov khoom.Qhov siab dua thermal conductivity ntawm cov khoom, qhov ntau dua qhov cuam tshuam ntawm qhov kub thiab txias (piv txwv li ???225°?=250?.?-1.?-1) thiab ???316?.225°?=19?.?-1.?-1) Qhov me me, qhov kub thiab txias dua.Aluminium alloy hmoov yog zoo heev rau kev siv kub kub vim lawv qhov kev nthuav dav ntxiv, thiab txawm tias cov khoom txias txias ua tau zoo dua flowability dua li cov hmoov qub.
Rau txhua qhov kev sim GranuPack, qhov loj ntawm cov hmoov tau sau tseg ua ntej txhua qhov kev sim, thiab cov qauv raug ntaus 500 zaug nrog kev cuam tshuam zaus ntawm 1 Hz nrog rau lub caij nplooj zeeg dawb ntawm 1 hli hauv lub ntsuas hluav taws xob (kev cuam tshuam lub zog ∝).Cov qauv no tau muab tso rau hauv qhov ntsuas ntawm tes raws li tus neeg siv khoom ywj pheej cov lus qhia software.Tom qab ntawd cov kev ntsuas tau rov ua dua ob zaug los ntsuas qhov rov ua dua thiab tshawb xyuas qhov nruab nrab thiab tus qauv sib txawv.
Tom qab kev soj ntsuam GranuPack tiav lawm, thawj qhov ntau ntom ntom (ρ(0)), qhov kawg ntawm qhov ntom ntom (ntawm ntau cov kais dej, n = 500, piv txwv li ρ(500)), Hausner piv / Carr Performance index (Hr / Cr) thiab ob qhov kev sau npe tsis tau (n1/2 thiab τ) ntsig txog kev cog lus kinetics.Qhov pom kev ceev ρ(∞) kuj tau qhia (saib Daim Ntawv Ntxiv 1).Cov lus hauv qab no restructures cov ntaub ntawv sim.
Cov nuj nqis 6 thiab 7 qhia tag nrho cov kab ke nkhaus (kev ceev ceev piv rau cov neeg cuam tshuam) thiab N1 / 2 / Lausner Parameter piv.Cov kab yuam kev suav nrog qhov nruab nrab yog qhia ntawm txhua qhov nkhaus, thiab cov qauv sib txawv tau suav los ntawm kev ntsuas rov ua dua.
316L stainless hlau khoom yog cov khoom hnyav tshaj plaws (ρ(0) = 4.554 g / mL).Nyob rau hauv cov nqe lus ntawm tapping ceev, SS 316L tseem yog cov hmoov hnyav tshaj plaws (ρ(n) = 5.044 g/mL), ua raws li cov qauv A (ρ(n) = 1.668 g/mL), ua raws li Sample B (ρ(n) = 1.668 g/ml)./ml) (n) = 1.645 g/ml).Qauv C yog qhov qis tshaj (ρ(n) = 1.581 g/mL).Raws li qhov ntom ntom ntawm cov hmoov pib, peb pom tias cov qauv A yog qhov sib sib zog nqus, thiab suav nrog qhov tsis raug (1.380 g / ml), cov qauv B thiab C muaj kwv yees li qub.
Raws li cov hmoov rhuab, nws cov Hausner piv txo qis, thiab qhov no tsuas yog tshwm sim nrog cov qauv B, C, thiab SS 316L.Rau cov qauv A, nws tsis tuaj yeem ua tau vim qhov loj ntawm qhov yuam kev tuav.Rau n1/2, qhov parametric sib qhia hauv qab yog qhov nyuaj dua.Rau cov qauv A thiab SS 316L, tus nqi ntawm n1/2 poob tom qab 2 h ntawm 200 ° C, thaum rau hmoov B thiab C nws nce tom qab thermal loading.
Lub vibrating feeder tau siv rau txhua qhov kev sim GranuCharge (saib daim duab 8).Siv 316L stainless hlau tubing.Kev ntsuas tau rov ua dua 3 zaug los ntsuas kev rov ua dua tshiab.Qhov hnyav ntawm cov khoom siv rau txhua qhov kev ntsuas yog kwv yees li 40 ml thiab tsis muaj hmoov zoo tom qab ntsuas.
Ua ntej qhov kev sim, qhov hnyav ntawm cov hmoov (mp, g), txheeb ze huab cua humidity (RH, %), thiab kub (° C) raug kaw.Thaum pib ntawm qhov kev xeem, tus nqi ceev ntawm cov hmoov thawj (q0 hauv µC / kg) tau ntsuas los ntawm kev muab cov hmoov tso rau hauv lub khob Faraday.Thaum kawg, cov hmoov loj tau ruaj khov thiab qhov kawg ntawm qhov ceev ceev (qf, µC / kg) thiab Δq (Δq = qf – q0) thaum kawg ntawm qhov kev sim tau suav.
Cov ntaub ntawv nyoos GranuCharge tau pom nyob rau hauv Table 2 thiab Daim duab 9 (σ yog tus qauv sib txawv suav los ntawm cov txiaj ntsig ntawm kev ntsuas kev rov tsim dua tshiab), thiab cov txiaj ntsig tau pom zoo li histogram (tsuas yog q0 thiab Δq tau pom).SS 316L muaj tus nqi qis tshaj plaws;qhov no yuav yog vim qhov tseeb tias cov khoom no muaj PSD siab tshaj plaws.Thaum nws los txog rau thawj zaug thauj khoom ntawm thawj aluminium alloy hmoov, tsis muaj kev txiav txim siab tuaj yeem kos vim qhov loj ntawm qhov yuam kev.
Tom qab kev sib cuag nrog 316L stainless hlau yeeb nkab, qauv A tau txais qhov tsawg kawg nkaus tus nqi, thaum cov hmoov B thiab C pom muaj qhov sib xws, yog tias SS 316L hmoov raug rubbed tawm tsam SS 316L, tus nqi them ze ze rau 0 tau pom (saib triboelectric series).Cov khoom B tseem raug them ntau dua li A. Rau cov qauv C, cov qauv txuas ntxiv (tus nqi pib zoo thiab tus nqi kawg tom qab xau), tab sis tus nqi ntawm cov nqi nce ntxiv tom qab thermal degradation.
Tom qab 2 teev ntawm thermal stress ntawm 200 ° C, tus cwj pwm ntawm cov hmoov yuav nthuav heev.Hauv cov qauv A thiab B, tus nqi pib poob qis thiab qhov kawg nqi hloov ntawm qhov tsis zoo mus rau qhov zoo.SS 316L hmoov muaj qhov siab tshaj plaws thawj zaug thiab nws cov nqi hloov pauv tau zoo tab sis tseem qis (piv txwv li 0.033 nC / g).
Peb tau tshawb xyuas qhov cuam tshuam ntawm thermal degradation ntawm kev coj tus cwj pwm ntawm txhuas alloy (AlSi10Mg) thiab 316L stainless hlau hmoov, thaum cov hmoov qub tau txheeb xyuas tom qab 2 teev ntawm 200 ° C hauv huab cua.
Kev siv cov hmoov ntawm qhov kub siab tuaj yeem txhim kho cov khoom lag luam, qhov cuam tshuam uas zoo li tseem ceeb dua rau cov hmoov uas muaj qhov tshwj xeeb thiab cov khoom siv nrog cov thermal conductivity.GranuDrum tau siv los ntsuas qhov ntws, GranuPack tau siv rau kev tsom xam cov khoom ntim dynamic, thiab GranuCharge tau siv los txheeb xyuas cov triboelectricity ntawm cov hmoov hauv kev sib cuag nrog 316L stainless hlau yeeb nkab.
Cov txiaj ntsig no tau txiav txim siab siv GranuPack, uas pom tau tias muaj kev txhim kho hauv Hausner coefficient rau txhua cov hmoov (nrog rau kev zam ntawm cov qauv A, vim qhov loj ntawm qhov yuam kev) tom qab cov txheej txheem thermal stress.Tsis muaj qhov pom meej meej pom rau cov khoom ntim khoom (n1/2) vim qee cov khoom tau pom qhov nce ntawm cov ntim ceev thaum lwm tus muaj qhov sib txawv (xws li Samples B thiab C).