1.1Tasirin HPMC akan buga turmi na 3D
1.1.1Sakamakon HPMC akan extrudability na 3D bugu turmi
Ƙungiyar M-H0 mara kyau ba tare da HPMC ba da kuma ƙungiyoyin gwaji tare da abun ciki na HPMC na 0.05%, 0.10%, 0.20%, da 0.30% an yarda su tsaya na lokuta daban-daban, sa'an nan kuma an gwada ruwa.Ana iya ganin cewa haɗawar HPMC zai rage yawan ruwa na turmi sosai;Lokacin da abun ciki na HPMC ya karu a hankali daga 0% zuwa 0.30%, farkon ruwa na turmi yana raguwa daga 243 mm zuwa 206, 191, 167, da 160 mm, bi da bi.HPMC babban nau'in polymer ne.Za a iya haɗa su da juna don samar da tsarin hanyar sadarwa, kuma ana iya ƙara haɗin slurry na ciminti ta hanyar haɗar abubuwa kamar Ca (OH) 2. Macroscopically, haɗin gwiwar turmi yana inganta.Tare da tsawaita lokacin tsayawa, matakin hydration na turmi yana ƙaruwa.ya karu, yawan ruwa ya ɓace akan lokaci.Rashin ruwa na rukunin M-H0 mara kyau ba tare da HPMC ya ragu da sauri ba.A cikin rukuni na gwaji tare da 0.05%, 0.10%, 0.20% da 0.30% HPMC, matakin raguwa a cikin ruwa ya ragu tare da lokaci, kuma yawan ruwa na turmi bayan tsayawa na 60 min shine 180, 177, 164, da 155 mm, bi da bi. .Ruwan ruwa shine 87.3%, 92.7%, 98.2%, 96.8%.Haɗin HPMC na iya haɓaka ƙarfin riƙewar turmi mai mahimmanci, wanda ya kasance saboda haɗuwa da kwayoyin HPMC da ruwa;a gefe guda kuma, HPMC na iya samar da irin wannan fim din Yana da tsarin hanyar sadarwa da kuma nannade siminti, wanda ya rage yadda ya kamata ya rage yawan ruwa a cikin turmi kuma yana da wani aikin riƙe ruwa.Ya kamata a lura cewa lokacin da abun ciki na HPMC ya kasance 0.20%, ikon riƙewar turmi ruwa ya kai matakin mafi girma.
A fluidity na 3D bugu turmi gauraye da daban-daban adadin HPMC ne 160 ~ 206 mm.Saboda ma'auni daban-daban na firinta, shawarwarin jeri na ruwa da aka samu ta hanyar masu bincike daban-daban sun bambanta, kamar 150 ~ 190 mm, 160 ~ 170 mm.Daga Hoto na 3, ana iya gani da idon basira Ana iya ganin cewa ruwan turmi na bugu na 3D wanda aka haɗe da HPMC galibi yana cikin kewayon da aka ba da shawarar, musamman lokacin da abun ciki na HPMC ya kai 0.20%, yawan ruwan turmi a cikin mintuna 60 yana tsakanin. kewayon da aka ba da shawarar, wanda ya gamsar da daidaitaccen ruwa da kuma tari.Sabili da haka, ko da yake an rage yawan ruwa na turmi tare da adadin da ya dace na HPMC, wanda ke haifar da raguwa a cikin extrudability, har yanzu yana da kyakkyawan extrudability, wanda ke cikin iyakar shawarar.
1.1.2Tasirin HPMC akan stackability na 3D bugu turmi
Idan ba a yi amfani da samfuri ba, girman girman siffar siffar da ke ƙarƙashin nauyin kai ya dogara ne akan yawan karuwar kayan aiki, wanda ke da alaƙa da haɗin kai na ciki tsakanin slurry da tarawa.An ba da siffar riƙe turmi na bugu na 3D tare da abubuwan HPMC daban-daban.Adadin canji tare da lokacin tsayawa.Bayan ƙara HPMC, ƙimar riƙewar sifa na turmi yana inganta, musamman a matakin farko da tsayawa na 20 min.Koyaya, tare da tsawaita lokacin tsayawa, ingantaccen sakamako na HPMC akan ƙimar riƙewar turmi a hankali ya raunana, wanda galibi saboda ƙimar riƙewar yana ƙaruwa sosai.Bayan tsayawa na 60 min, kawai 0.20% da 0.30% HPMC na iya inganta ƙimar riƙewar turmi.
Ana nuna sakamakon gwajin juriya na shigar ciki na turmi bugu na 3D tare da abubuwan da ke cikin HPMC daban-daban a cikin Hoto 5. Ana iya gani daga Hoto 5 cewa juriya na shigar gabaɗaya yana ƙaruwa tare da tsawaita lokacin tsayawa, wanda galibi saboda kwarara na slurry a lokacin aikin siminti hydration.A hankali ya rikide ya zama m;a cikin mintuna na 80 na farko, haɗakarwar HPMC ta haɓaka juriya ta shiga, kuma tare da haɓakar abun ciki na HPMC, juriya na shigar ya karu.Mafi girman juriya na shiga ciki, nakasar kayan saboda nauyin da aka yi amfani da shi Mafi girma juriya na HPMC shine, wanda ke nuna cewa HPMC na iya inganta farkon stackability na 3D bugu turmi.Tun da hydroxyl da ether bond a kan polymer sarkar na HPMC ana sauƙi a hade tare da ruwa ta hanyar hydrogen shaidu, sakamakon da sannu a hankali rage free ruwa da kuma alaka tsakanin barbashi karuwa, da gogayya karfi karuwa, don haka farkon shigar juriya ya zama mafi girma.Bayan tsayawa na minti 80, saboda hydration na ciminti, juriya na shigar da rukunin marasa amfani ba tare da HPMC ya karu da sauri ba, yayin da juriyar shigar da ƙungiyar gwaji tare da HPMC ya karu Adadin bai canza sosai ba har kusan 160 min na tsaye.A cewar Chen et al., wannan ya fi saboda HPMC ya samar da fim mai kariya a kusa da barbashi na siminti, wanda ke tsawaita lokacin saitawa;Pourchez et al.zaton cewa wannan shi ne yafi saboda fiber Simple ether lalata kayayyakin (kamar carboxylates) ko methodyl kungiyoyin iya jinkirta ciminti hydration ta retarding samuwar Ca (OH) 2.Ya kamata a lura da cewa, domin hana ci gaban shigar juriya daga lalacewa ta hanyar evaporation na ruwa a saman samfurin, An gudanar da wannan gwaji a karkashin yanayin zafi da zafi iri ɗaya.Gabaɗaya, HPMC na iya inganta ingantaccen turmi na bugu na 3D a matakin farko, jinkirta coagulation, da tsawaita lokacin bugu na turmi bugu na 3D.
3D bugu turmi mahaluži (tsawon 200 mm × nisa 20 mm × Layer kauri 8 mm): The blank kungiyar ba tare da HPMC aka tsanani nakasu, rugujewa da kuma samun zub da jini matsaloli a lokacin da bugu na bakwai Layer;Turmi rukuni na M-H0.20 yana da kyakkyawan tari.Bayan bugu 13 yadudduka, saman gefen nisa shine 16.58 mm, nisa gefen ƙasa shine 19.65 mm, kuma rabo na sama zuwa ƙasa (rabo na nisa na saman gefen zuwa nisa na ƙasa) shine 0.84.Matsakaicin girman ƙarami ne.Don haka, an tabbatar da bugu cewa haɗa HPMC na iya inganta ingantaccen bugun turmi.Turmi fluidity yana da kyau extrudability da stackability a 160 ~ 170 mm;Adadin riƙe siffar bai wuce 70 % yana da naƙasa sosai kuma ba zai iya biyan buƙatun bugu ba.
1.2Tasirin HPMC akan kaddarorin rheological na 3D bugu turmi
Ana ba da alamar danko mai tsafta a ƙarƙashin nau'in abun ciki na HPMC daban-daban: tare da haɓaka ƙimar juzu'i, bayyanar danko mai tsabta na ɓangaren litattafan almara yana raguwa, kuma sabon abu na bakin ciki mai ƙarfi yana ƙarƙashin babban abun ciki na HPMC.Ya fi bayyana.Sarkar kwayoyin halittar HPMC ba ta da matsala kuma tana nuna danko mafi girma a ƙananan ƙimar ƙarfi;amma a babban juzu'i, kwayoyin HPMC suna tafiya a layi daya da tsari tare da juzu'i, suna sa kwayoyin su zama mafi sauki don zamewa, don haka tebur Bayyanar danko na slurry yayi kadan.Lokacin da adadin shear ya fi 5.0 s-1, bayyanar danko na P-H0 a cikin rukunin da ba kowa ba ya tabbata a cikin 5 Pa s;yayin da slurry na fili yana ƙaruwa bayan an ƙara HPMC, kuma an haɗa shi da HPMC.Bugu da ƙari na HPMC yana ƙara haɓakar ciki tsakanin simintin siminti, wanda ke ƙara yawan danko na manna, kuma aikin macroscopic shine cewa extrudability na 3D bugu turmi yana raguwa.
Dangantakar da ke tsakanin danniya mai karfi da raguwar slurry mai tsabta a cikin gwajin rheological an rubuta, kuma an yi amfani da samfurin Bingham don dacewa da sakamakon.Ana nuna sakamakon a cikin Hoto 8 da Table 3. Lokacin da abun ciki na HPMC ya kasance 0.30%, ƙimar raguwa a lokacin gwajin ya fi 32.5 Lokacin da danko na slurry ya wuce kewayon kayan aiki a s-1, bayanan da suka dace. Ba za a iya tattara maki ba.Gabaɗaya, yankin da ke kewaye da masu lanƙwasa masu tasowa da faɗuwa a cikin kwanciyar hankali (10.0 ~ 50.0 s-1) ana amfani da shi don siffata thixotropy na slurry [21, 33].Thixotropy yana nufin kadarorin da slurry yana da ruwa mai yawa a ƙarƙashin aikin ɓarkewar ƙarfi na waje, kuma zai iya komawa zuwa ainihin yanayinsa bayan an soke aikin shearing.Daidaitaccen thixotropy yana da matukar mahimmanci ga buguwar turmi.Ana iya gani daga Hoto 8 cewa yanki na thixotropic na rukunin mara kyau ba tare da HPMC ba shine kawai 116.55 Pa / s;bayan ƙara 0.10% na HPMC, yankin thixotropic na net manna ya karu sosai zuwa 1 800.38 Pa / s;Tare da karuwa na , yankin thixotropic na manna ya ragu, amma har yanzu ya kasance sau 10 mafi girma fiye da na rukunin maras kyau.Daga hangen nesa na thixotropy, haɗawar HPMC ya inganta ingantaccen bugun turmi.
Domin turmi ya kula da siffarsa bayan extrusion kuma ya jure nauyin nauyin da ke gaba, turmi yana buƙatar samun damuwa mai girma.Ana iya gani daga Table 3 cewa yawan damuwa τ0 na net slurry yana inganta sosai bayan an ƙara HPMC, kuma yana kama da HPMC.Abubuwan da ke cikin HPMC suna da alaƙa da alaƙa;lokacin da abun ciki na HPMC ya kasance 0.10%, 0.20%, da 0.30%, yawan yawan damuwa na net ɗin yana ƙaruwa zuwa 8.6, 23.7, da 31.8 sau na ƙungiyar mara kyau, bi da bi;Dankowar filastik μ kuma yana ƙaruwa tare da haɓaka abun ciki na HPMC.Buga 3D yana buƙatar cewa dankon filastik na turmi bai kamata ya zama ƙanƙanta ba, in ba haka ba nakasar bayan extrusion zai zama babba;a lokaci guda, ya kamata a kiyaye danko mai dacewa na filastik don tabbatar da daidaiton fitar da kayan aiki.A taƙaice, daga ra'ayi na rheology, HPMC's Incorporation yana da tasiri mai kyau a kan inganta tari na 3D bugu turmi.Bayan haɗa HPMC, madaidaicin manna har yanzu yana dacewa da ƙirar rheological Bingham, kuma kyawun dacewa R2 bai ƙasa da 0.99 ba.
1.3Tasirin HPMC akan kayan aikin injiniya na 3D bugu turmi
28 d ƙarfin matsawa da ƙarfin sassauƙa na turmi bugu na 3D.Tare da karuwar abun ciki na HPMC, 28 d matsawa da ƙarfin sassauƙa na turmi bugu na 3D ya ragu;lokacin da abun ciki na HPMC ya kai 0.30%, ƙarfin matsawa na 28 d da Ƙarfin flexural shine 30.3 da 7.3 MPa, bi da bi.Nazarin ya nuna cewa HPMC yana da wani tasiri mai hana iska, kuma idan abun ciki ya yi yawa, porosity na ciki na turmi zai karu sosai;Juriya na yadawa yana ƙaruwa kuma yana da wahala a fitar da duka.Saboda haka, karuwar porosity na iya zama dalilin raguwar ƙarfin 3D bugu turmi lalacewa ta hanyar HPMC.
Tsarin gyare-gyaren lamination na musamman na bugu na 3D yana haifar da wanzuwar wurare masu rauni a cikin tsari da kaddarorin injina tsakanin yadudduka da ke kusa, kuma ƙarfin haɗin kai tsakanin yadudduka yana da tasiri mai girma a kan gaba ɗaya ƙarfin da aka buga.Don samfuran turmi bugu na 3D gauraye da 0.20% HPMC M-H0.20 an yanke, kuma an gwada ƙarfin haɗin kai ta hanyar hanyar tsagawar interlayer.Ƙarfin haɗin haɗin gwiwa na sassa uku ya fi 1.3 MPa;kuma lokacin da adadin yadudduka ya yi ƙasa, ƙarfin haɗin gwiwa ya ɗan ƙara girma.Dalili na iya zama cewa, a gefe guda, nauyin nauyin saman saman yana sa ƙananan yadudduka sun fi haɗuwa;a daya bangaren kuma, saman turmi na iya samun karin danshi a lokacin da ake buga kasan Layer, yayin da danshin saman turmi ya ragu saboda fitar da ruwa da ruwa yayin da ake buga saman saman, don haka hadawa tsakanin sassan kasa ya fi karfi.
1.4Tasirin HPMC akan Micromorphology na 3D Printing Turmi
Hotunan SEM na samfurin M-H0 da M-H0.20 a cikin shekaru 3 sun nuna cewa raƙuman ruwa na samfurin M-H0.20 suna karuwa sosai bayan ƙara 0.20% HPMC, kuma girman pore ya fi girma fiye da na kungiyar mara komai.Wannan A gefe guda, shi ne saboda HPMC yana da tasirin iska, wanda ke gabatar da uniform da ƙananan pores;a gefe guda, yana iya zama ƙari na HPMC yana ƙara danko na slurry, don haka ƙara juriya na fitar da iska a cikin slurry.Ƙaruwar na iya zama babban dalilin raguwa a cikin kayan aikin injiniya na turmi.Don taƙaitawa, don tabbatar da ƙarfin turmi bugu na 3D, abun ciki na HPMC bai kamata ya zama babba ba (≤ 0.20%).
A karshe
(1) Hydroxypropyl methylcellulose HPMC yana inganta bugun turmi.Tare da karuwar abun ciki na HPMC, ƙaddamarwar turmi yana raguwa amma har yanzu yana da kyau extrudability, stackability yana inganta, kuma ana iya bugawa Lokaci yana tsawaita.An tabbatar da shi ta hanyar buga cewa an rage nakasar kasan Layer na turmi bayan ƙara HPMC, kuma rabo na sama-kasa shine 0.84 lokacin da abun ciki na HPMC ya kasance 0.20%.
(2) HPMC inganta rheological Properties na 3D bugu turmi.Tare da haɓakar abun ciki na HPMC, danko na fili, yawan damuwa da ƙarancin filastik na haɓakar slurry;thixotropy na farko yana ƙaruwa sannan kuma yana raguwa, kuma ana samun bugu.Ingantawa.Daga hangen nesa na rheology, ƙara HPMC kuma na iya inganta bugun turmi.Bayan ƙara HPMC, slurry har yanzu ya dace da ƙirar rheological Bingham, da kuma kyawun dacewa R2≥0.99.
(3) Bayan ƙara HPMC, microstructure da pores na kayan haɓaka.An ba da shawarar cewa abun ciki na HPMC bai kamata ya wuce 0.20% ba, in ba haka ba zai yi tasiri sosai akan kayan aikin injiniya na turmi.Ƙarfin haɗin kai tsakanin yadudduka daban-daban na turmi bugu na 3D ya ɗan bambanta, kuma adadin yadudduka Lokacin da ya ragu, ƙarfin haɗin kai tsakanin yadudduka turmi ya fi girma.
Lokacin aikawa: Satumba-27-2022