Muna amfani da kukis don inganta ƙwarewar ku. Ta hanyar ci gaba da bincika wannan rukunin yanar gizon, kun yarda da amfani da kukis ɗinmu. Ƙarin Bayani.
Ƙirƙirar ƙari (AM) ta ƙunshi ƙirƙirar abubuwa 3D, wani Layer ɗaya mai siriri sosai a lokaci guda, wanda hakan ya sa ya fi tsada fiye da sarrafa gargajiya. Duk da haka, ƙaramin ɓangare ne kawai na foda ake haɗa shi da kayan yayin haɗa su. Sauran ba sa haɗuwa, don haka ana iya sake amfani da su. Sabanin haka, idan an ƙirƙiri abin ta hanyar gargajiya, yawanci yana buƙatar niƙa da injina don cire kayan.
Halayen foda suna ƙayyade sigogin injin kuma dole ne a yi la'akari da su tun farko. Farashin AM ba zai yi tsada ba idan aka yi la'akari da cewa foda mara narkewa ya gurɓata kuma ba za a iya sake amfani da shi ba. Lalacewar foda yana haifar da abubuwa biyu: gyaran sinadarai na samfurin da canje-canje a cikin halayen injiniya kamar yanayin halitta da rarraba girman barbashi.
A yanayin farko, babban aikin shine ƙirƙirar tsarukan da ke ɗauke da sinadarai masu tsabta, don haka muna buƙatar guje wa gurɓatar foda, misali, da oxides ko nitrides. A cikin wannan lamari na ƙarshe, waɗannan sigogi suna da alaƙa da ruwa da kuma yaduwarsa. Saboda haka, duk wani canji a cikin halayen foda na iya haifar da rarraba samfurin ba tare da daidaito ba.
Bayanai daga wallafe-wallafen da aka buga kwanan nan sun nuna cewa na'urorin auna ruwa na gargajiya ba za su iya samar da isasshen bayani game da rarraba foda a cikin AM bisa ga gadon foda ba. Dangane da yanayin kayan (ko foda), akwai hanyoyi da dama masu dacewa a kasuwa waɗanda za su iya biyan wannan buƙata. Yanayin damuwa da filin kwararar foda dole ne su kasance iri ɗaya a cikin saitin aunawa da kuma cikin tsari. Kasancewar nauyin matsi bai dace da kwararar saman kyauta da ake amfani da ita a cikin na'urorin IM a cikin masu gwajin yanke da na'urorin rheometer na gargajiya ba.
GranuTools ta ƙirƙiro tsarin aiki don siffanta foda na AM. Babban burinmu shine samar da kayan aikin kwaikwayo na tsari mai inganci ga kowane tsari, kuma ana amfani da wannan tsarin aiki don fahimtar da bin diddigin ci gaban ingancin foda a cikin hanyoyin bugawa daban-daban. An zaɓi ƙarfe da yawa na aluminum (AlSi10Mg) na yau da kullun don tsawon lokaci daban-daban a cikin nauyin zafi daban-daban (daga 100 zuwa 200 °C).
Ana iya sarrafa lalacewar zafi ta hanyar nazarin ikon foda na tara cajin lantarki. An yi nazarin foda don samun sauƙin gudana (kayan aikin GranuDrum), kinetics na marufi (kayan aikin GranuPack) da kuma halin lantarki (kayan aikin GranuCharge). Ma'aunin haɗin kai da marufi sun dace don bin diddigin ingancin foda.
Foda mai sauƙin shafawa zai nuna ƙarancin ma'aunin haɗin kai, yayin da foda mai saurin cikawa zai samar da sassan injina tare da ƙarancin porosity idan aka kwatanta da samfuran da suka fi wahalar cikawa.
Bayan watanni da dama na ajiya a dakin gwaje-gwajenmu, an zaɓi foda guda uku na aluminum tare da rarrabawar girman barbashi daban-daban (AlSi10Mg) da kuma samfurin ƙarfe mai bakin ƙarfe 316L ɗaya, wanda aka ambata a nan a matsayin samfurori A, B da C. Halayen samfuran na iya bambanta da sauran masana'antun. An auna rarrabawar girman barbashi ta hanyar nazarin diffraction na laser/ISO 13320.
Domin suna sarrafa sigogin injin, dole ne a fara la'akari da halayen foda, kuma idan foda mara narkewa an ɗauke shi gurɓatacce kuma ba za a iya sake amfani da shi ba, to kera ƙarin kayan ba shi da arha kamar yadda ake tsammani. Saboda haka, za a binciki sigogi uku: kwararar foda, yanayin marufi da electrostatics.
Yaɗuwa yana da alaƙa da daidaito da kuma “santsi” na layin foda bayan aikin sake shafa shi. Wannan yana da matuƙar muhimmanci domin saman da ke da santsi suna da sauƙin bugawa kuma ana iya bincika su da kayan aikin GranuDrum tare da ma'aunin mannewa.
Saboda ramukan suna da rauni a cikin wani abu, suna iya haifar da tsagewa. Tsarin cikawa shine ma'auni na biyu mai mahimmanci saboda foda mai cikewa da sauri yana ba da ƙarancin ramuka. Ana auna wannan ɗabi'ar da GranuPack tare da ƙimar n1/2.
Kasancewar cajin lantarki a cikin foda yana haifar da ƙarfin haɗin kai wanda ke haifar da samuwar agglomerates. GranuCharge yana auna ikon foda don samar da cajin lantarki lokacin da ya haɗu da kayan da aka zaɓa yayin kwarara.
A lokacin sarrafawa, GranuCharge na iya hango lalacewar kwarara, misali, lokacin da ake samar da wani Layer a cikin AM. Don haka, ma'aunin da aka samu suna da matukar tasiri ga yanayin saman hatsi (haɗari, gurɓatawa da rashin ƙarfi). Sannan ana iya auna tsufan foda da aka dawo da shi daidai (±0.5 nC).
GranuDrum hanya ce ta auna kwararar foda da aka tsara bisa ga ƙa'idar ganga mai juyawa. Rabin samfurin foda yana cikin silinda mai kwance tare da bangon gefe mai haske. Gangar tana juyawa a kusa da axis ɗinta a saurin kusurwa na 2 zuwa 60 rpm, kuma kyamarar CCD tana ɗaukar hotuna (daga hotuna 30 zuwa 100 a tazara ta daƙiƙa 1). Ana gano hanyar haɗin iska/foda akan kowane hoto ta amfani da algorithm na gano gefuna.
Lissafa matsakaicin matsayi na hanyar sadarwa da kuma juyawar da ke kewaye da wannan matsakaicin matsayi. Ga kowane saurin juyawa, ana ƙididdige kusurwar kwarara (ko "kusurwar hutawa mai ƙarfi") αf daga matsakaicin matsayi na hanyar sadarwa, kuma ana nazarin yanayin haɗin kai mai ƙarfi σf da ke da alaƙa da haɗin gwiwar ƙwayoyin halitta daga canjin hanyar sadarwa.
Kusurwar kwarara tana shafar sigogi da dama: gogayya, siffa da haɗin kai tsakanin barbashi (van der Waals, ƙarfin electrostatic da capillary). Foda masu haɗin kai suna haifar da kwararar da ba ta da alaƙa da juna, yayin da foda marasa ƙamshi ke haifar da kwararar da ta dace. Ƙananan ƙimar kusurwar kwarara αf sun dace da kwarara mai kyau. Ma'aunin mannewa mai ƙarfi kusa da sifili ya yi daidai da foda mara haɗin kai, don haka yayin da mannewar foda ke ƙaruwa, ma'aunin mannewa yana ƙaruwa daidai gwargwado.
GranuDrum yana ba ku damar auna kusurwar farko ta zaftarewar ƙasa da kuma iskar foda yayin kwararar, da kuma auna ma'aunin mannewa σf da kuma kusurwar kwarara αf dangane da saurin juyawa.
Yawan girman GranuPack, yawan tapping da kuma ma'aunin rabon Hausner (wanda kuma aka sani da "gwajin tapping") sun dace da halayen foda saboda sauƙinsu da saurin aunawa. Yawan girman foda da ikon ƙara yawansa muhimman sigogi ne yayin ajiya, jigilar kaya, tattarawa, da sauransu. An tsara hanyoyin da aka ba da shawarar a cikin Pharmacopoeia.
Wannan gwaji mai sauƙi yana da manyan matsaloli guda uku. Ma'aunin ya dogara da mai aiki, kuma hanyar cikawa tana shafar girman farko na foda. Auna jimlar girman na iya haifar da manyan kurakurai a cikin sakamakon. Saboda sauƙin gwajin, ba mu yi la'akari da yanayin matsewa tsakanin ma'aunin farko da na ƙarshe ba.
An yi nazarin halayen foda da aka zuba a cikin mashigar da ke ci gaba ta amfani da kayan aiki na atomatik. A auna ma'aunin Hausner Hr daidai, yawan farko ρ(0) da yawan ƙarshe ρ(n) bayan danna n.
Adadin famfo yawanci ana ƙayyade shi ne a n=500. GranuPack ma'aunin yawan famfo ne mai sarrafa kansa kuma mai ci gaba bisa ga binciken da aka yi kwanan nan.
Ana iya amfani da wasu fihirisa, amma ba a bayar da su a nan ba. Ana sanya foda a cikin bututun ƙarfe ta hanyar tsari mai tsauri na farawa ta atomatik. An cire ƙarin sigar motsi mai ƙarfi n1/2 da matsakaicin yawan ρ(∞) daga lanƙwasa mai matsewa.
Silinda mai sauƙi mai rami tana zaune a saman gadon foda don kiyaye matakin haɗin foda/iska yayin matsewa. Bututun da ke ɗauke da samfurin foda yana tashi zuwa tsayin ΔZ mai tsayi kuma yana faɗuwa cikin 'yanci a tsayin da yawanci aka saita a ΔZ = 1 mm ko ΔZ = 3 mm, wanda ake aunawa ta atomatik bayan kowane taɓawa. Lissafa ƙarar V na tarin daga tsayin.
Yawan yawa shine rabon taro m zuwa girman Layer na foda V. An san nauyin foda m, ana amfani da yawan ρ bayan kowane tasiri.
Hausner coefficient Hr yana da alaƙa da matsi kuma ana nazarinsa ta hanyar lissafin Hr = ρ(500) / ρ(0), inda ρ(0) shine farkon yawan girma da ρ(500) shine ƙididdigar kwararar bayan zagayowar 500. Tap ɗin yawa. Lokacin amfani da hanyar GranuPack, ana iya sake samar da sakamako ta amfani da ƙaramin adadin foda (yawanci 35 ml).
Halayen foda da kuma halayen kayan da aka yi na'urar su ne muhimman sigogi. A lokacin kwararar, ana samar da cajin lantarki a cikin foda saboda tasirin triboelectric, wanda shine musayar caji lokacin da daskararru biyu suka hadu.
Lokacin da foda ke gudana a cikin na'urar, tasirin triboelectric yana faruwa ne a lokacin da aka haɗu tsakanin barbashi da kuma lokacin da aka haɗu tsakanin barbashi da na'urar.
Da zarar an taɓa kayan da aka zaɓa, GranuCharge yana auna adadin wutar lantarki da aka samar a cikin foda ta atomatik yayin kwarara. Samfurin foda yana gudana a cikin bututun V mai girgiza kuma yana faɗa cikin kofin Faraday wanda aka haɗa da na'urar auna wutar lantarki wanda ke auna cajin da aka samu yayin da foda ke motsawa a cikin bututun V. Don sakamakon sake samarwa, yi amfani da na'urar juyawa ko girgiza don ciyar da bututun V akai-akai.
Tasirin triboelectric yana sa wani abu ya sami electrons a saman sa don haka ya zama mara caji, yayin da wani abu kuma ya rasa electrons don haka ya zama mara caji. Wasu kayan suna samun electrons cikin sauƙi fiye da wasu, haka nan kuma, wasu kayan suna rasa electrons cikin sauƙi.
Wanne abu ne ya zama mara kyau kuma wanda ya zama mai kyau ya dogara ne da yanayin kayan da ke tattare da samun ko rasa electrons. Don wakiltar waɗannan yanayin, an ƙirƙiri jerin triboelectric da aka nuna a cikin Jadawali na 1. An jera kayan da ke da yanayin caji mai kyau da wasu waɗanda ke da yanayin caji mara kyau, kuma an jera hanyoyin kayan da ba su nuna wani yanayin halayya ba a tsakiyar teburin.
A gefe guda kuma, teburin yana ba da bayanai ne kawai game da yanayin da ake ciki a cikin yanayin caji na kayan aiki, don haka an ƙirƙiri GranuCharge don samar da daidaitattun ƙimomin lambobi don yanayin caji na foda.
An gudanar da gwaje-gwaje da dama don yin nazarin ruɓewar zafi. An sanya samfuran a zafin 200°C na tsawon sa'o'i ɗaya zuwa biyu. Sannan nan da nan aka yi nazarin foda da GranuDrum (sunan zafi). Daga nan aka sanya foda a cikin akwati har sai ya kai yanayin zafi na yanayi sannan aka yi nazarin ta amfani da GranuDrum, GranuPack da GranuCharge (watau "sanyi").
An yi nazarin samfuran da ba a sarrafa ba ta amfani da GranuPack, GranuDrum da GranuCharge a danshi/zafin ɗaki ɗaya (watau 35.0 ± 1.5% RH da zafin jiki 21.0 ± 1.0 °C).
Ma'aunin haɗin kai yana ƙididdige ƙarfin kwararar foda kuma yana da alaƙa da canje-canje a matsayin mahaɗin (foda/iska), wanda ƙarfin hulɗa guda uku ne kawai (van der Waals, capillary da electrostatic forces). Kafin gwajin, an yi rikodin ɗanɗanon iska (RH, %) da zafin jiki (°C). Sannan aka zuba foda a cikin ganga, kuma gwajin ya fara.
Mun kammala da cewa waɗannan samfuran ba sa fuskantar haɗarin haɗuwa yayin la'akari da sigogin thixotropic. Abin sha'awa, damuwa ta zafi ta canza halayen rheological na foda na samfuran A da B daga kauri mai kauri zuwa ƙaiƙayin mai kauri. A gefe guda kuma, Samfuran C da SS 316L ba su shafi yanayin zafi ba kuma sun nuna kauri mai kauri kawai. Kowane foda yana da ingantaccen yaduwarwa (watau ƙarancin ma'aunin haɗin kai) bayan dumama da sanyaya.
Tasirin zafin jiki kuma ya dogara ne akan takamaiman yankin ƙwayoyin. Mafi girman ƙarfin jurewar zafi na kayan, mafi girman tasirin akan zafin jiki (misali ???225°?=250??.-1.?-1) da ???316??. 225°?=19??.-1.?-1) Ƙaramin ƙwayar, mafi girman tasirin zafin jiki. Foda na ƙarfe na aluminum suna da kyau don amfani da zafin jiki mai yawa saboda ƙaruwar yaduwar su, har ma samfuran da aka sanyaya suna samun ingantaccen kwarara fiye da foda na asali.
Ga kowace gwaji ta GranuPack, an rubuta nauyin foda kafin kowace gwaji, kuma an buga samfurin sau 500 tare da mitar tasiri na 1 Hz tare da faɗuwar 1 mm kyauta a cikin ƙwayar aunawa (ƙarfin tasiri ∝). Ana rarraba samfurin a cikin ƙwayar aunawa bisa ga umarnin software mai zaman kansa na mai amfani. Sannan an maimaita ma'aunin sau biyu don tantance yuwuwar sake samarwa kuma an bincika matsakaicin karkacewar da ta dace.
Bayan an kammala nazarin GranuPack, yawan girman farko (ρ(0)), yawan girman ƙarshe (a wurare da yawa, n = 500, watau ρ(500)), rabon Hausner/Carr index (Hr/Cr) da sigogin rajista guda biyu (n1/2 da τ) waɗanda suka shafi motsin matsa lamba. Hakanan an nuna mafi kyawun yawan ρ(∞) (duba Shafi na 1). Teburin da ke ƙasa ya sake tsara bayanan gwaji.
Sifofi na 6 da 7 suna nuna jimlar lanƙwasawa (yawan yawa idan aka kwatanta da adadin tasirin) da kuma rabon sigogin n1/2/Hausner. An nuna sandunan kuskure da aka ƙididdige ta amfani da matsakaicin akan kowane lanƙwasa, kuma an ƙididdige daidaitattun karkacewa ta hanyar gwajin maimaitawa.
Samfurin ƙarfe mai nauyin lita 316 shine samfurin da ya fi nauyi (ρ(0) = 4.554 g/mL). Dangane da yawan tapping, SS 316L ya kasance foda mafi nauyi (ρ(n) = 5.044 g/mL), sai Samfurin A (ρ(n) = 1.668 g/mL), sai Samfurin B (ρ(n) = 1.668 g/mL). /ml) (n) = 1.645 g/mL). Samfurin C shine mafi ƙanƙanta (ρ(n) = 1.581 g/mL). Dangane da yawan adadin foda na farko, mun ga cewa samfurin A shine mafi sauƙi, kuma idan aka yi la'akari da kurakuran (1.380 g/mL), samfuran B da C suna da kusan ƙimar iri ɗaya.
Yayin da ake dumama foda, rabon Hausner ɗinsa yana raguwa, kuma wannan yana faruwa ne kawai da samfuran B, C, da SS 316L. Ga samfurin A, ba zai yiwu a yi ba saboda girman sandunan kuskuren. Ga n1/2, yanayin parametric da ke ƙarƙashin ƙasa ya fi rikitarwa. Ga samfurin A da SS 316L, ƙimar n1/2 ta ragu bayan awanni 2 a 200°C, yayin da ga foda B da C ya ƙaru bayan loda zafi.
An yi amfani da na'urar ciyar da abinci mai girgiza don kowace gwaji ta GranuCharge (duba Hoto na 8). Yi amfani da bututun ƙarfe mai nauyin L 316. An maimaita ma'auni sau 3 don tantance yuwuwar sake haifuwa. Nauyin samfurin da aka yi amfani da shi don kowane ma'auni shine kusan 40 ml kuma babu foda da aka dawo da shi bayan aunawa.
Kafin gwajin, an rubuta nauyin foda (mp, g), danshi na iska (RH, %), da zafin jiki (°C). A farkon gwajin, an auna yawan cajin foda na farko (q0 a cikin µC/kg) ta hanyar sanya foda a cikin kofin Faraday. A ƙarshe, an daidaita nauyin foda kuma an ƙididdige yawan cajin ƙarshe (qf, µC/kg) da Δq (Δq = qf – q0) a ƙarshen gwajin.
An nuna bayanan GranuCharge marasa inganci a cikin Jadawali na 2 da Hoto na 9 (σ shine daidaitaccen karkacewa da aka ƙididdige daga sakamakon gwajin sake samarwa), kuma an nuna sakamakon a matsayin histogram (q0 da Δq kawai aka nuna). SS 316L yana da mafi ƙarancin caji na farko; wannan na iya zama saboda gaskiyar cewa wannan samfurin yana da mafi girman PSD. Idan ana maganar ɗaukar farko na babban foda na aluminum, ba za a iya yanke hukunci ba saboda girman kurakuran.
Bayan an taɓa bututun ƙarfe mai nauyin 316L, samfurin A ya sami mafi ƙarancin adadin caji, yayin da foda B da C suka nuna irin wannan yanayin, idan aka shafa foda SS 316L akan SS 316L, an sami yawan caji kusa da 0 (duba jerin triboelectric). Samfurin B har yanzu yana da caji fiye da A. Ga samfurin C, yanayin yana ci gaba (cajin farko mai kyau da cajin ƙarshe bayan zubewa), amma adadin caji yana ƙaruwa bayan lalacewar zafi.
Bayan awanni 2 na matsin lamba na zafi a 200 °C, halayen foda ya zama mai ban sha'awa sosai. A cikin samfuran A da B, cajin farko ya ragu kuma cajin ƙarshe ya canza daga negative zuwa positive. Foda SS 316L tana da mafi girman cajin farko kuma canjin yawan cajinsa ya zama positive amma ya kasance ƙasa (watau 0.033 nC/g).
Mun binciki tasirin lalacewar zafi akan haɗin gwiwar haɗin gwiwar ƙarfe na aluminum (AlSi10Mg) da foda na bakin ƙarfe 316L, yayin da aka yi nazarin asalin foda bayan awanni 2 a zafin 200°C a cikin iska.
Amfani da foda a yanayin zafi mai yawa zai iya inganta kwararar samfura, wani tasiri da ya fi muhimmanci ga foda mai takamaiman yanki da kayan da ke da yawan kwararar zafi. An yi amfani da GranuDrum don kimanta kwarara, an yi amfani da GranuPack don nazarin marufi mai ƙarfi, kuma an yi amfani da GranuCharge don nazarin ƙarfin lantarki na foda a cikin bututun ƙarfe mai nauyin 316L.
An tantance waɗannan sakamakon ta amfani da GranuPack, wanda ya nuna ci gaba a cikin ma'aunin Hausner na kowane foda (banda samfurin A, saboda girman kurakuran) bayan tsarin damuwa na zafi. Ba a sami wani yanayi bayyananne ba game da ma'aunin marufi (n1/2) yayin da wasu samfura suka nuna ƙaruwa a saurin marufi yayin da wasu kuma suka sami tasirin bambanci (misali Samfuran B da C).