Timagwiritsa ntchito makeke kuti tiwongolere luso lanu.Mukapitiliza kusakatula tsamba ili, mukuvomera kugwiritsa ntchito ma cookie.Zina Zowonjezera.
Kupanga zowonjezera (AM) kumaphatikizapo kupanga zinthu zitatu-dimensional, wosanjikiza umodzi wowonda kwambiri panthawi imodzi, zomwe zimapangitsa kuti zikhale zodula kuposa makina achikhalidwe.Komabe, gawo laling'ono lokha la ufa lomwe limayikidwa panthawi ya msonkhano limagulitsidwa m'chigawocho.Zina ndiye sizisungunuka, kotero zitha kugwiritsidwanso ntchito.Mosiyana ndi zimenezi, ngati chinthucho chimapangidwa mwachikale, kuchotsa zinthu ndi mphero ndi Machining nthawi zambiri kumafunika.
Makhalidwe a ufa amatsimikizira magawo a makinawo ndipo ayenera kuganiziridwa poyamba.Mtengo wa AM ungakhale wopanda chuma chifukwa chakuti ufa wosasungunuka ndi woipitsidwa komanso wosasinthika.Kuwonongeka kwa ufa kumabweretsa zochitika ziwiri: kusintha kwa mankhwala a mankhwala ndi kusintha kwa makina monga morphology ndi kugawa kwa tinthu.
Pachiyambi choyamba, ntchito yaikulu ndiyo kupanga mapangidwe olimba omwe ali ndi ma alloys oyera, choncho tiyenera kupewa kuipitsidwa ndi ufa, mwachitsanzo, ndi oxides kapena nitrides.Pamapeto pake, magawowa amagwirizanitsidwa ndi fluidity ndi kufalikira.Choncho, kusintha kulikonse muzinthu za ufa kungayambitse kugawa kosafanana kwa mankhwala.
Deta kuchokera m'mabuku posachedwapa zimasonyeza kuti tingachipeze powerenga flowmeters sangapereke chidziwitso chokwanira pa ufa flowability kupanga ufa bedi zina.Ponena za mawonekedwe a zopangira (kapena ufa), pali njira zingapo zoyenera zoyezera pamsika zomwe zingakwaniritse izi.Kupsinjika maganizo ndi gawo la ufa liyenera kukhala lofanana mu selo yoyezera komanso panthawiyi.Kukhalapo kwa katundu wopondereza sikumagwirizana ndi kutulutsa kwaulere pamtunda komwe kumagwiritsidwa ntchito mu zida za AM mu zoyesa ma cell a shear ndi ma rheometer akale.
GranuTools yapanga ma workflows a ufa popanga zowonjezera.Cholinga chathu chachikulu chinali kukhala ndi chida chimodzi pa geometry yolondola, ndipo kayendedwe ka ntchito kameneka kanagwiritsidwa ntchito kumvetsetsa ndi kutsata kusinthika kwaubwino wa ufa pamadutsa angapo osindikiza.Ma aloyi angapo a aluminiyamu (AlSi10Mg) adasankhidwa kwa nthawi yayitali pamatenthedwe osiyanasiyana (kuyambira 100 mpaka 200 ° C).
Kuwonongeka kwa kutentha kumatha kuwongoleredwa pofufuza kuthekera kwa ufa kusungira ndalama.Mafutawa adawunikidwa kuti azitha kuyenda (chida cha GranuDrum), kulongedza kinetics (chida cha GranuPack) ndi khalidwe la electrostatic (chida cha GranuCharge).Miyezo ya mgwirizano ndi kulongedza kinetics ilipo pamagulu otsatirawa a ufa.
Ufa womwe umafalikira mosavuta umakhala ndi index yotsika yolumikizana, pomwe ufa wokhala ndi mphamvu zodzaza mwachangu udzatulutsa zida zamakina zokhala ndi porosity yochepa poyerekeza ndi zinthu zomwe zimakhala zovuta kudzaza.
Mafuta atatu a aluminiyamu aloyi (AlSi10Mg) omwe amasungidwa mu labotale yathu kwa miyezi ingapo, ndi magawo osiyanasiyana a tinthu tating'onoting'ono, ndi chitsanzo chimodzi chachitsulo chosapanga dzimbiri cha 316L, chomwe chimatchulidwa pano ngati zitsanzo A, B ndi C, adasankhidwa.Makhalidwe a zitsanzo angakhale osiyana ndi ena.opanga.Kugawa kwa tinthu kakang'ono kuyesedwa ndi kusanthula kwa laser diffraction/ISO 13320.
Popeza amalamulira magawo a makinawo, katundu wa ufa ayenera kuganiziridwa poyamba, ndipo ngati tiganizira kuti ufa wosasungunuka ukhale woipitsidwa komanso wosasinthika, mtengo wopangira zowonjezera sudzakhala wachuma monga momwe tingafunira.Chifukwa chake, magawo atatu adzafufuzidwa: kutuluka kwa ufa, kunyamula kinetics ndi electrostatics.
Kufalikira kumagwirizana ndi kufanana ndi "kusalala" kwa ufa wosanjikiza pambuyo pa ntchito yokonzanso.Izi ndizofunika kwambiri chifukwa malo osalala ndi osavuta kusindikiza ndipo amatha kufufuzidwa ndi chida cha GranuDrum chokhala ndi miyeso yolumikizira.
Chifukwa pores ndi mfundo zofooka muzinthu, zimatha kuyambitsa ming'alu.Kulongedza mphamvu ndi gawo lachiwiri lofunika kwambiri chifukwa ufa wonyamula mofulumira uli ndi porosity yochepa.Khalidweli layesedwa ndi GranuPack yokhala ndi mtengo wa n1/2.
Kukhalapo kwa magetsi mu ufa kumapanga mphamvu zogwirizanitsa zomwe zimapangitsa kuti pakhale ma agglomerates.GranuCharge imayesa kuthekera kwa ufa kuti upangitse chiwongola dzanja cha electrostatic pokhudzana ndi chinthu chomwe chasankhidwa panthawi yoyenda.
Pakukonza, GranuCharge imatha kuneneratu kuwonongeka kwa kayendedwe kake, monga kusanjikiza mu AM.Choncho, miyeso yopezedwa imakhudzidwa kwambiri ndi chikhalidwe cha tirigu (oxidation, kuipitsidwa ndi roughness).Kukalamba kwa ufa wopezekanso kumatha kuwerengedwa molondola (± 0.5 nC).
GranuDrum imachokera pa mfundo ya ng'oma yozungulira ndipo ndi njira yopangidwira yoyezera kutuluka kwa ufa.Silinda yopingasa yokhala ndi makoma ammbali owonekera imakhala ndi theka la zitsanzo za ufa.Ng'oma imazungulira mozungulira pamtunda wake pamtunda wa 2 mpaka 60 rpm, ndipo kamera ya CCD imatenga zithunzi (kuchokera pa 30 mpaka 100 zithunzi pa 1 mphindi).Mawonekedwe a mpweya/ufa amadziwika pachithunzi chilichonse pogwiritsa ntchito njira yodziwira m'mphepete.
Werengani kuchuluka kwa mawonekedwe a mawonekedwe ndi ma oscillation mozungulira malo awa.Pa liwiro lililonse lozungulira, ngodya yotuluka (kapena "dynamic angle of repose") αf imawerengeredwa kuchokera kumtunda wapakati, ndipo dynamic adhesion index σf, yomwe imatanthawuza kugwirizanitsa pakati, imawunikidwa kuchokera ku kusintha kwa mawonekedwe.
Kuthamanga kwapakati kumakhudzidwa ndi magawo angapo: kukangana pakati pa tinthu tating'ono, mawonekedwe ndi mgwirizano (van der Waals, electrostatic ndi capillary forces).Kuphatikizika kwa ufa kumabweretsa kutuluka kwapakatikati, pamene ufa wosagwirizanitsa umapangitsa kuyenda nthawi zonse.Zing'onozing'ono za angle yothamanga αf zimayenderana ndi katundu wabwino.Chizindikiro chokhazikika chokhazikika pafupi ndi zero chimagwirizana ndi ufa wosagwirizanitsa, choncho, pamene kuphatikizika kwa ufa kumawonjezeka, ndondomeko yowonjezera imakula molingana.
GranuDrum imakulolani kuti muyese mbali ya chiwombankhanga choyamba ndi mpweya wa ufa panthawi yothamanga, komanso kuyeza ndondomeko yomatira σf ndi kayendedwe ka αf malingana ndi liwiro lozungulira.
GranuPack kachulukidwe kachulukidwe, kachulukidwe kachulukidwe ndi miyeso ya Hausner (yomwe imatchedwanso "mayeso okhudza") ndizodziwika kwambiri pamayendedwe a ufa chifukwa chosavuta komanso liwiro la kuyeza.Kachulukidwe wa ufa ndi kuthekera kuonjezera kachulukidwe ake magawo zofunika pa kusungirako, zoyendera, agglomeration, etc. Njira yovomerezeka ikufotokozedwa mu Pharmacopoeia.
Mayeso osavutawa ali ndi zovuta zazikulu zitatu.Miyezo imadalira opareshoni ndipo njira yodzaza imakhudza kuchuluka kwa ufa woyamba.Kuyeza kowoneka kwa mphamvu kungayambitse zolakwika zazikulu muzotsatira.Chifukwa cha kuphweka kwa kuyesako, tinanyalanyaza kusinthasintha kwapakati pakati pa miyeso yoyamba ndi yomaliza.
Khalidwe la ufa wodyetsedwa m'malo otuluka mosalekeza adawunikidwa pogwiritsa ntchito zida zamagetsi.Yezerani molondola coefficient ya Hausner Hr, kachulukidwe koyambirira ρ(0) ndi kachulukidwe komaliza ρ(n) pambuyo pa kudina kwa n.
Chiwerengero cha matepi nthawi zambiri chimakhazikika pa n=500.GranuPack ndi muyeso wokhazikika komanso wotsogola wa kachulukidwe kutengera kafukufuku waposachedwa kwambiri.
Ma index ena angagwiritsidwe ntchito, koma sanalembedwe apa.Ufawo umayikidwa mu machubu achitsulo ndipo umadutsa munjira yokhazikika yoyambira.The extrapolation of the dynamic parameter n1/2 and the maximum density ρ(∞) amatengedwa pa compaction curve.
Silinda yopepuka yopepuka imakhala pamwamba pa bedi la ufa kuti isunge mawonekedwe a ufa/mpweya panthawi yophatikizika.Chubu chomwe chili ndi chitsanzo cha ufa chimakwera kufika pamtunda wokhazikika ∆Z ndiyeno chimagwera momasuka pamtunda, nthawi zambiri chimakhazikika pa ∆Z = 1 mm kapena ∆Z = 3 mm, yoyesedwa yokha pambuyo pa zotsatira zilizonse.Mwa kutalika, mutha kuwerengera voliyumu V ya muluwo.
Kachulukidwe ndi chiŵerengero cha misa m ku voliyumu V ya wosanjikiza wa ufa.Kuchuluka kwa ufa m kumadziwika, kachulukidwe ρ amagwiritsidwa ntchito pakatulutsidwa kulikonse.
Coefficient ya Hausner Hr imagwirizana ndi kuchuluka kwa kuphatikizika ndipo imawunikidwa ndi equation Hr = ρ(500) / ρ(0), pomwe ρ(0) ndiye kachulukidwe koyambirira ndipo ρ(500) ndiye kuchuluka kwapampopi komwe kumawerengedwa pambuyo pa 500. matepi.Zotsatira zimabwerezedwa ndi ufa wochepa (kawirikawiri 35 ml) pogwiritsa ntchito njira ya GranuPack.
Makhalidwe a ufa ndi chikhalidwe cha zinthu zomwe chipangizocho chimapangidwira ndizofunika kwambiri.Pa otaya, milandu electrostatic kwaiye mkati ufa, ndipo milandu izi amayamba ndi zotsatira triboelectric, kusinthanitsa milandu pamene zolimba awiri kukumana.
Pamene ufa umayenda mkati mwa chipangizocho, zotsatira za triboelectric zimachitika pa kukhudzana pakati pa tinthu tating'onoting'ono ndi kukhudzana pakati pa tinthu ndi chipangizocho.
Mukakumana ndi zinthu zomwe zasankhidwa, GranuCharge imadziyesa yokha kuchuluka kwa electrostatic charge yopangidwa mkati mwa ufa pakuyenda.Chitsanzo cha ufa chimayenda mu V-chubu chogwedezeka ndikugwera mu kapu ya Faraday yolumikizidwa ndi electrometer yomwe imayesa mtengo umene ufa umapeza pamene ukudutsa mu V-chubu.Kuti muwone zotsatira, dyetsani V-chubu pafupipafupi ndi chipangizo chozungulira kapena chonjenjemera.
Mphamvu ya triboelectric imapangitsa kuti chinthu chimodzi chipeze ma electron pamwamba pake ndipo motero chimayimbidwa molakwika, pamene chinthu china chimataya ma elekitironi motero chimayimitsidwa bwino.Zida zina zimapeza ma elekitironi mosavuta kuposa zina, ndipo chimodzimodzi, zida zina zimataya ma elekitironi mosavuta.
Ndi zinthu ziti zomwe zimakhala zoipa ndipo zomwe zimakhala zabwino zimatengera chizolowezi chazinthu zomwe zimakhudzidwa kuti zipeze kapena kutaya ma elekitironi.Kuyimira izi, mndandanda wa triboelectric womwe ukuwonetsedwa mu Table 1 unapangidwa.Zida zomwe zimakonda kukhala zolipiridwa bwino komanso zina zomwe zimakonda kukhala ndi mlandu woyipa zimalembedwa, pomwe zida zomwe sizikuwonetsa zizolowezi zamakhalidwe zimalembedwa pakati pa tebulo.
Kumbali inayi, tebulo ili limangopereka chidziwitso pamayendedwe azinthu zolipiritsa, kotero GranuCharge idapangidwa kuti ipereke zolondola zamakhalidwe a ufa.
Kuyesera kangapo kunachitika kuti aunike kuwonongeka kwa kutentha.Zitsanzozo zinasiyidwa pa 200 ° C kwa ola limodzi kapena awiri.Kenako ufawo umawunikidwa nthawi yomweyo ndi GranuDrum (dzina lotentha).Kenaka ufawo umayikidwa mu chidebe mpaka utafika kutentha kozungulira kenako ndikuwunikiridwa pogwiritsa ntchito GranuDrum, GranuPack ndi GranuCharge (ie "kuzizira").
Zitsanzo zaiwisi zidawunikidwa pogwiritsa ntchito GranuPack, GranuDrum ndi GranuCharge pa kutentha komweko / kutentha kwachipinda, mwachitsanzo chinyezi 35.0 ± 1.5% ndi kutentha 21.0 ± 1.0 °C.
Mlozera wa mgwirizano umawerengera kutuluka kwa ufa ndikugwirizanitsa ndi kusintha kwa mawonekedwe a mawonekedwe (ufa / mpweya), zomwe zimasonyeza mphamvu zitatu zokha zolumikizana (van der Waals, capillary ndi electrostatic).Musanayambe kuyesa, lembani chinyezi (RH, %) ndi kutentha (°C).Kenaka tsanulirani ufa mu chidebe cha ng'oma ndikuyamba kuyesa.
Tinaona kuti mankhwalawa sanali tcheru kwa caking poganizira thixotropic magawo.Chochititsa chidwi n'chakuti, kupsinjika kwa kutentha kunasintha khalidwe la rheological la ufa wa zitsanzo A ndi B kuchoka ku kumeta ubweya wa ubweya mpaka kumeta ubweya wa ubweya.Kumbali ina, Zitsanzo C ndi SS 316L sizinakhudzidwe ndi kutentha ndipo zimangowonetsa kumeta ubweya wa ubweya.Ufa uliwonse unkawonetsa kufalikira kwabwinoko (mwachitsanzo, mlozera wochepa wa mgwirizano) utatha kutentha ndi kuzizira.
Kutentha kwake kumadaliranso malo enieni a particles.Kuchuluka kwa kutentha kwa zinthuzo, kumakhudzanso kutentha (ie ???225°?=250?.?-1.?-1) ndi ?316?225°?=19?.?-1.?-1), tinthu tating'onoting'ono, m'pamenenso kutentha kumakhala kofunika kwambiri.Kugwira ntchito pamtunda wokwera ndi chisankho chabwino cha ufa wa aluminiyamu aloyi chifukwa cha kufalikira kwawo, ndipo zitsanzo zoziziritsa zimapindula bwino kwambiri poyerekeza ndi ufa wa pristine.
Pakuyesa kulikonse kwa GranuPack, kulemera kwa ufa kunalembedwa musanayambe kuyesa kulikonse, ndipo chitsanzocho chinakhudzidwa ndi zotsatira za 500 ndi mphamvu yafupipafupi ya 1 Hz ndi kugwa kwaulere kwa selo yoyezera ya 1 mm (mphamvu yamphamvu ∝).Zitsanzo zimaperekedwa m'maselo oyezera molingana ndi malangizo a mapulogalamu osadalira wogwiritsa ntchito.Miyezoyo idabwerezedwa kawiri kuti awone kuberekana ndikuwunika tanthauzo ndi kupatuka kokhazikika.
Kusanthula kwa GranuPack kukamalizidwa, kachulukidwe koyambira (ρ(0)), kachulukidwe komaliza (pa kudina kangapo, n = 500, ie ρ(500)), Hausner ratio/Carr index (Hr/Cr) , ndi ziwiri zojambulidwa. magawo (n1/2 ndi τ) okhudzana ndi kuphatikizika kwamphamvu.Kachulukidwe koyenera ρ(∞) akuwonetsedwanso (onani Zowonjezera 1).Tebulo ili m'munsiyi ikukonzekera deta yoyesera.
Zithunzi 6 ndi 7 zikuwonetsa ma curve ophatikizika onse (kachulukidwe kachulukidwe ndi kuchuluka kwa zotsatira) ndi n1/2/Hausner parameter ratio.Mipiringidzo yolakwika yowerengedwera pogwiritsa ntchito ma avareji imawonetsedwa pamakhota aliwonse, ndipo mipatuko yokhazikika idawerengedwa kuchokera ku mayeso obwerezabwereza.
Chitsulo chosapanga dzimbiri cha 316L chinali cholemera kwambiri (ρ(0) = 4.554 g/mL).Pankhani ya kachulukidwe ka kugunda, SS 316L ikadali ufa wolemera kwambiri (ρ(n) = 5.044 g/mL), kutsatiridwa ndi Chitsanzo A (ρ(n) = 1.668 g/mL), kutsatiridwa ndi Chitsanzo B (ρ (n) = 1.668 g/ml) (n) = 1.645 g/ml).Chitsanzo C chinali chotsikitsitsa (ρ(n) = 1.581 g/mL).Malingana ndi kuchuluka kwa ufa woyambirira, tikuwona kuti chitsanzo A ndi chopepuka kwambiri, ndipo poganizira zolakwika (1.380 g / ml), zitsanzo B ndi C zili ndi mtengo wofanana.
Pamene ufa umatenthedwa, chiŵerengero chake cha Hausner chimachepa, chomwe chimapezeka kokha kwa zitsanzo B, C ndi SS 316L.Pachitsanzo A, izi sizingachitike chifukwa cha kukula kwa zolakwikazo.Kwa n1/2, mawonekedwe a parameter ndi ovuta kuzindikira.Kwa chitsanzo A ndi SS 316L, mtengo wa n1 / 2 unatsika pambuyo pa 2 h pa 200 ° C, pamene ufa wa B ndi C unawonjezeka pambuyo potengera kutentha.
Chodyetsa chogwedeza chinagwiritsidwa ntchito pa kuyesa kulikonse kwa GranuCharge (onani Chithunzi 8).Gwiritsani ntchito chitoliro cha 316L chosapanga dzimbiri.Miyezo idabwerezedwa 3 nthawi kuti awone kuberekana.Kulemera kwa chinthu chomwe chinagwiritsidwa ntchito pa muyeso uliwonse chinali pafupifupi 40 ml ndipo palibe ufa umene unapezedwa pambuyo poyeza.
Asanayambe kuyesa, kulemera kwa ufa (mp, g), chinyezi cha mpweya (RH, %), ndi kutentha (° C) zimalembedwa.Kumayambiriro kwa mayeso, yesani kuchuluka kwa mtengo wa ufa woyambirira (q0 mu µC/kg) poyambitsa ufawo mu kapu ya Faraday.Pomaliza, lembani kuchuluka kwa ufa ndikuwerengera kuchuluka kwa ndalama zomaliza (qf, µC / kg) ndi Δq (Δq = qf - q0) kumapeto kwa kuyesa.
Deta ya GranuCharge yaiwisi yaiwisi ikuwonetsedwa mu Table 2 ndi Chithunzi 9 (σ ndiyo njira yowonongeka yowerengedwa kuchokera ku zotsatira za kuyesa kwa reproducibility), ndipo zotsatira zimaperekedwa monga histograms (q0 ndi Δq okha akuwonetsedwa).SS 316L inali ndi mtengo wotsikitsitsa woyamba;izi zitha kukhala chifukwa chakuti mankhwalawa ali ndi PSD yapamwamba kwambiri.Ponena za kuchuluka kwa ndalama zoyambira za ufa woyambirira wa aluminiyamu alloy, palibe malingaliro omwe angaganizidwe chifukwa cha kukula kwa zolakwikazo.
Pambuyo pokhudzana ndi chitoliro chachitsulo chosapanga dzimbiri cha 316L, chitsanzo A chinapeza ndalama zochepa poyerekeza ndi ufa wa B ndi C, zomwe zikuwonetseratu zomwezo, pamene SS 316L ufa wopaka ndi SS 316L, kachulukidwe kake pafupi ndi 0 amapezeka (onani triboelectric). mndandanda).Chogulitsa B chidakali cholipiritsa kuposa A. Pachitsanzo C, zomwe zimachitika zimapitilira (malipiro abwino oyamba ndi mtengo womaliza pambuyo pa kutayikira), koma kuchuluka kwa zolipiritsa kumawonjezeka pambuyo pakuwonongeka kwamafuta.
Pambuyo pa maola a 2 akupsinjika kwa kutentha pa 200 ° C, khalidwe la ufa limakhala lochititsa chidwi.Mu zitsanzo A ndi B, mtengo woyambira umachepa ndipo mtengo womaliza umasintha kuchoka ku zoyipa kupita ku zabwino.SS 316L ufa unali ndi malipiro apamwamba kwambiri ndipo kusintha kwa kachulukidwe kake kunakhala kolimbikitsa koma kunakhalabe kochepa (ie 0.033 nC / g).
Tinafufuza zotsatira za kuwonongeka kwa matenthedwe pa khalidwe lophatikizana la aluminiyamu alloy (AlSi10Mg) ndi 316L zitsulo zosapanga dzimbiri za ufa pamene tikusanthula ma ufa oyambirira mu mpweya wozungulira pambuyo pa maola awiri pa 200 ° C.
Kugwiritsiridwa ntchito kwa ufa pa kutentha kwakukulu kungapangitse kufalikira kwa mankhwala, ndipo izi zikuwoneka kuti ndizofunikira kwambiri kwa ufa wokhala ndi malo apamwamba komanso zipangizo zomwe zimakhala ndi matenthedwe apamwamba.GranuDrum idagwiritsidwa ntchito kuwunika kuyenda, GranuPack idagwiritsidwa ntchito powunikira kudzaza kwamphamvu, ndipo GranuCharge idagwiritsidwa ntchito kusanthula triboelectricity ya ufa pokhudzana ndi 316L chitsulo chosapanga dzimbiri chubu.
Zotsatirazi zinakhazikitsidwa pogwiritsa ntchito GranuPack, zomwe zikuwonetsa kusintha kwa Hausner coefficient pa ufa uliwonse (kupatulapo chitsanzo A chifukwa cha zolakwika za kukula) pambuyo pa ndondomeko ya kutentha kwa kutentha.Kuyang'ana pazigawo zonyamula katundu (n1/2), panalibe zochitika zomveka bwino monga zinthu zina zimawonetsa kuwonjezeka kwa liwiro la kulongedza pamene zina zinali ndi zotsatira zosiyana (mwachitsanzo Zitsanzo B ndi C).
Nthawi yotumiza: Jan-10-2023