1.1Kupesvedzera kweHPMC pakudhinda kwe3D dhaka rekudhinda
1.1.1Mhedzisiro yeHPMC pane extrudability ye3D yekudhinda dhaka
Iro boka risina chinhu M-H0 risina HPMC uye mapoka ekuedza ane HPMC zvinyorwa zve 0.05%, 0.10%, 0.20%, uye 0.30% vakabvumirwa kumira kwenguva dzakasiyana-siyana, uye ipapo fluidity yakaedzwa.Zvinogona kuonekwa kuti kubatanidzwa kweHPMC Ichanyanya kuderedza fluidity yematope;apo zvinyorwa zveHPMC zvishoma nezvishoma zvichiwedzera kubva ku0% kusvika ku0.30%, iyo yekutanga fluidity yedhaka inoderera kubva 243 mm kusvika 206, 191, 167, uye 160 mm, maererano.HPMC ndeyepamusoro molecular polymer.Vanogona kusungirirwa kune mumwe nemumwe kuti vagadzire hurongwa hwemambure, uye kuwirirana kwe simenti slurry inogona kuwedzerwa ne encapsulating zvikamu zvakadai seCa (OH) 2. Macroscopically, kuwirirana kwevhu kunovandudzwa.Nekuwedzera kwenguva yakamira, chiyero che hydration yedhaka chinowedzera.kuwedzera, mvura yakarasika nekufamba kwenguva.Iyo fluidity yeboka risina chinhu M-H0 isina HPMC yakaderera nekukurumidza.Muboka rekuedza rine 0.05%, 0.10%, 0.20% uye 0.30% HPMC, dhigirii yekuderera kwemvura yakaderera nekufamba kwenguva, uye fluidity yematope mushure mekumira kwemaminitsi makumi matanhatu yaiva 180, 177, 164, uye 155 mm, zvichiteerana. .Iyo fluidity ndeye 87.3%, 92.7%, 98.2%, 96.8%.Kubatanidzwa kweHPMC kunogona kuvandudza zvakanyanya kukwanisa kwekuchengetedza kwedhaka fluidity, iyo inokonzerwa nekubatanidzwa kweHPMC nemamolekemu emvura;kune rumwe rutivi, HPMC inogona kuumba yakafanana firimu Iine network network uye inoputira simende, iyo inobudirira inoderedza kuvhuvhuta kwemvura mudhaka uye ine imwe nzira yekuchengetedza mvura.Izvo zvakakosha kucherechedza kuti kana zvirimo zveHPMC zviri 0.20%, kugona kwekuchengetedza kwedhaka fluidity kunosvika padanho repamusoro.
Iyo fluidity ye3D yekudhinda dhaka yakasanganiswa nehuwandu hwakasiyana hweHPMC ndeye 160 ~ 206 mm.Nekuda kweakasiyana maparamendi eprinta, iyo yakakurudzirwa siyana ye fluidity inowanikwa nevaongorori vakasiyana yakasiyana, senge 150 ~ 190 mm, 160 ~ 170 mm.Kubva Mufananidzo 3, inogona kuonekwa intuitively Zvinogona kuonekwa kuti fluidity ye 3D kudhinda dhaka yakasanganiswa neHPMC inonyanya mukati mehutano hwakakurudzirwa, kunyanya kana HPMC iine 0.20%, iyo fluidity yematope mukati memaminitsi makumi matanhatu ari mukati. iyo yakakurudzirwa siyana, iyo inogutsa iyo yakakodzera fluidity uye stackability.Nokudaro, kunyange zvazvo kunyunguduka kwedhaka nehupamhi hwakakodzera hweHPMC kunoderedzwa, izvo zvinotungamirira kuderera kwekuwedzera, inoramba iine extrudability yakanaka, iyo iri mukati mehutano hwakakurudzirwa.
1.1.2Mhedzisiro yeHPMC pane stackability ye3D yekudhinda dhaka
Muchiitiko chekusashandisa template, ukuru hwechimiro chekuchengetedza chiyero pasi pehuremu hunoenderana nekunetseka kwegoho rezvinyorwa, izvo zvinoenderana nekubatana kwemukati pakati pe slurry uye aggregate.Iko kuchengetwa kwechimiro che3D yekudhinda dhaka neyakasiyana HPMC zvirimo inopihwa.Mwero wekuchinja nenguva yakamira.Mushure mekuwedzera HPMC, chiyero chekuchengetedza chimiro chedhaka chinovandudzwa, kunyanya padanho rekutanga uye kumira kwemaminetsi makumi maviri.Zvisinei, nekuwedzera kwenguva yakamira, maitiro ekuvandudza kweHPMC pane chimiro chekuchengetedza chiyero chevhu zvishoma nezvishoma chakapera simba, icho chainyanya kukonzerwa neThe retention rate inowedzera zvakanyanya.Mushure mekumira kwemaminetsi makumi matanhatu, chete 0.20% uye 0.30% HPMC inogona kuvandudza chimiro chekuchengetedza dhaka.
Mhedzisiro yekupikiswa kwekuedza mhedzisiro ye3D yekudhindisa dhaka ine zvakasiyana HPMC zviri mukati inoratidzwa muMufananidzo 5. Inogona kuonekwa kubva kuMufananidzo 5 kuti kupikisa kwekupinda kunowanzowedzera nekuwedzera kwenguva yakamira, iyo inonyanya kukonzerwa nekuyerera kwe slurry panguva ye simenti hydration process.Yakashanduka zvishoma nezvishoma ikava yakasimba yakasimba;mune yekutanga 80 min, kubatanidzwa kweHPMC kwakawedzera kupikisa kwekupinda, uye nekuwedzera kwemukati weHPMC, kupikisa kwekupinda kwakawedzera.Iyo yakakura kupikisa kwekupinda, deformation yezvinhu nekuda kwemutoro wakaiswa Iyo yakakura kupikisa kweHPMC ndeye, iyo inoratidza kuti HPMC inogona kuvandudza yekutanga stackability ye3D yekudhinda dhaka.Sezvo iyo hydroxyl uye ether zvisungo pa polymer cheni yeHPMC inosanganiswa nyore nyore nemvura kuburikidza nehydrogen zvisungo, zvichikonzera kudzikiswa zvishoma nezvishoma kwemvura yemahara uye kubatana pakati pezvimedu kunowedzera, simba rekukwenya rinowedzera, saka kurwisa kwekutanga kwekupinda kunova kwakakura.Mushure mekumira kwemaminetsi makumi masere, nekuda kwe hydration ye simenti, kupindira kwekupinda kweboka risina HPMC kwakawedzera nekukurumidza, nepo kupindira kweboka rekuedza neHPMC kwakawedzera Muyero hauna kuchinja zvakanyanya kusvikira anenge 160 min yekumira.Sekureva kwaChen et al., izvi zvinonyanya nekuti HPMC inoumba firimu rinodzivirira rakatenderedza masimende masimende, ayo anowedzera nguva yekuisa;Pourchez et al.zvinofungidzirwa kuti izvi zvinonyanya kukonzerwa nefiber Nyore ether degradation zvigadzirwa (senge carboxylates) kana methoxyl mapoka anogona kunonoka simende hydration nekudzoreredza kuumbwa kweCa (OH)2.Zvakakosha kucherechedza kuti, kuitira kudzivirira kukura kwekudzivirira kwekupinda kubva pakukanganiswa nekubuda kwemvura pamusoro pemuenzaniso, Kuedza uku kwakaitwa pasi pemamiriro akafanana ekushisa uye hunyoro.Pazere, HPMC inogona kunyatso kuvandudza kugadzikana kweiyo 3D yekudhinda dhaka padanho rekutanga, kunonoka kubatanidzwa, uye kurebesa nguva inodhinda ye3D yekudhinda dhaka.
3D printing mortar entity (kureba 200 mm × width 20 mm × layer thickness 8 mm): Boka risina chinhu risina HPMC rakaremara zvakanyanya, rakaputsika uye rakava nezvinetso zvekubuda ropa pakudhinda chikamu chechinomwe;Iyo M-H0.20 boka redhaka rine yakanaka stackability.Mushure mekudhinda mitsara gumi nenhatu, kumucheto kwepamusoro kukafara 16.58 mm, kumucheto kwepasi kufara i 19.65 mm, uye reshiyo yekumusoro kusvika pasi (reshiyo yehupamhi hwekumucheto kwepamusoro kusvika kuhupamhi hwepasi) i0,84.Dimensional kutsauka idiki.Naizvozvo, zvakasimbiswa nekudhinda kuti kubatanidzwa kweHPMC kunogona kuvandudza zvakanyanya kudhindwa kwedhaka.Mortar fluidity ine yakanaka extrudability uye stackability pa 160 ~ 170 mm;chiyero chekuchengetedza chimiro chiri pasi pe70 % chakaremara zvakanyanya uye hachikwanise kuita zvinodiwa pakudhinda.
1.2Kupesvedzera kweHPMC pane rheological zvimiro zve 3D dhinda dhaka
Iyo inooneka viscosity yepulp yakachena pasi pezvakasiyana HPMC zvemukati inopihwa: nekuwedzera kweshear rate, iyo inooneka viscosity ye pure pulp inodzikira, uye chiitiko chekuveura kutetepa chiri pasi peyakakwira HPMC yemukati.Zviri pachena.Iyo HPMC molecular chain yakakanganiswa uye inoratidza yakakwirira viscosity pane yakaderera shear rate;asi pahupamhi hwekugera, HPMC mamorekuru anofamba achienderana uye akarongeka achitevedza nzira yekugera, zvichiita kuti mamorekuru ave nyore kutsvedza, saka tafura Iyo inooneka viscosity ye slurry yakaderera.Kana shear rate yakakura kudarika 5.0 s-1, iyo inooneka viscosity yeP-H0 muboka risina chinhu inonyanya kugadzikana mukati me5 Pa s;nepo viscosity inooneka yeslurry inowedzera mushure mekunge HPMC yawedzerwa, uye inosanganiswa neHPMC.Kuwedzerwa kweHPMC kunowedzera kukakavara kwemukati pakati pemasimende zvimedu, izvo zvinowedzera kuoneka viscosity yenamira, uye macroscopic performance ndeyekuti extrudability ye3D yekudhinda dhaka inoderera.
Ukama huri pakati pekuveura kushushikana uye shear mwero weiyo yakachena slurry muyedzo yerheological yakanyorwa, uye muenzaniso weBingham wakashandiswa kuenderana nemhedzisiro.Zvigumisiro zvinoratidzwa muMufananidzo 8 uye Tafura 3. Apo zvinyorwa zveHPMC zvaiva 0.30%, shear rate panguva yekuedzwa yakanga yakakura kudarika 32.5 Apo viscosity ye slurry inodarika huwandu hwechiridzwa pa s-1, data inoenderana. pfungwa hadzigone kuunganidzwa.Kazhinji, nzvimbo yakakomberedzwa nekukwira nekudonha macurves munhanho yakagadzikana (10.0 ~ 50.0 s-1) inoshandiswa kuratidza thixotropy ye slurry [21, 33].Thixotropy inoreva pfuma iyo slurry ine fluidity yakakura pasi pechiito chekunze kwesimba rekuveura, uye inogona kudzokera kumamiriro ayo ekutanga mushure mekuita kwekuveura kwakabviswa.Yakakodzera thixotropy inonyanya kukosha kune kudhindwa kwedhaka .Inogona kuonekwa kubva kuMufananidzo 8 kuti nzvimbo yethixotropic yeboka risina HPMC yaingova 116.55 Pa / s chete;mushure mekuwedzera 0.10% yeHPMC, nzvimbo yethixotropic yenet paste yakawedzera zvakanyanya kusvika 1 800.38 Pa / s;Nekuwedzera kwe, nzvimbo yethixotropic yenamira yakaderera, asi yakanga ichiri yakapetwa ka10 kupfuura iyo yeboka risina chinhu.Kubva pakuona kwethixotropy, kubatanidzwa kweHPMC kwakavandudza zvakanyanya kudhindwa kwedhaka.
Kuti dhaka richengetedze chimiro chayo mushure mekuwedzera uye kuti rimire mutoro weiyo inotevera extruded layer, dhaka rinoda kuva nekunetseka kwegoho repamusoro.Zvinogona kuonekwa kubva Tafura 3 kuti goho stress τ0 of the net slurry inovandudzwa zvakanyanya mushure mokunge HPMC yawedzerwa, uye yakafanana neHPMC.Zviri mukati meHPMC zvakabatana zvakanaka;apo zvinyorwa zveHPMC zviri 0.10%, 0.20%, uye 0.30%, kushushikana kwegoho remambure paste kunowedzera kusvika 8.6, 23.7, uye 31.8 nguva yeboka risina chinhu, maererano;iyo plastiki viscosity μ inowedzerawo nekuwedzera kwezviri mukati meHPMC.3D Kudhinda kunoda kuti viscosity yepurasitiki yedhaka haifanire kunge iri diki, zvikasadaro deformation mushure meextrusion ichave yakakura;panguva imwecheteyo, yakakodzera plastiki viscosity inofanirwa kuchengetedzwa kuti ive nechokwadi chekuenderana kwezvinhu extrusion.Muchidimbu, kubva pakuona kwe rheology, HPMC's Incorporation ine mhedzisiro yakanaka pakuvandudzwa kwekusimba kwe3D yekudhinda dhaka.Mushure mekubatanidza HPMC, iyo yakachena paste ichiri kuenderana neBingham rheological modhi, uye kunaka kweiyo fit R2 haina kuderera pane 0.99.
1.3Mhedzisiro yeHPMC pane mechaniki zvivakwa zve 3D yekudhinda dhaka
28 d inomanikidza simba uye inoshanduka simba ye3D yekudhinda dhaka.Nekuwedzera kwehuwandu hweHPMC, iyo 28 d compressive uye flexural simba ye3D yekudhinda dhaka yakaderera;apo zvirimo zveHPMC zvasvika 0.30%, iyo 28 d compressive simba uye The flexural simba ndeye 30.3 uye 7.3 MPa, zvichiteerana.Zvidzidzo zvakaratidza kuti HPMC ine imwe mweya-entraining effect, uye kana zvinyorwa zvayo zvakanyanyisa, iyo porosity yemukati yedhaka ichawedzera zvakanyanya;The diffusion resistance inowedzera uye zvakaoma kuburitsa zvese.Naizvozvo, kuwedzera kweporosity kunogona kunge kuri chikonzero chekudzikira kwesimba re3D yekudhinda dhaka inokonzerwa neHPMC.
Iyo yakasarudzika lamination molding process ye 3D kudhinda inotungamira kune kuvepo kwenzvimbo dzisina kusimba muchimiro uye michina zvivakwa pakati pematanho ari padyo, uye kusimba kwekubatanidza pakati pematanho kune simba guru pakusimba kwese kwechikamu chakadhindwa.Kune 3D yekudhinda dhaka zvienzaniso zvakasanganiswa ne0.20% HPMC M-H0.20 yakachekwa, uye iyo interlayer bond simba yakaedzwa neiyo interlayer kupatsanura nzira.Iyo interlayer bond simba rezvikamu zvitatu raive rakakwirira kupfuura 1.3 MPa;uye apo nhamba yezvikamu zvaive zvishoma, iyo interlayer bond simba yakanga yakakwirira zvishoma.Chikonzero chinogona kunge chiri chekuti, kune rumwe rutivi, giravhiti rekumusoro rinoita kuti zvidimbu zvezasi zvibatanidzwe zvakanyanya;kune rumwe rutivi, pamusoro pedhaka inogona kuva nehunyoro hwakawanda kana ichidhinda chikamu chezasi, nepo hunyoro hwepamusoro hwedhaka hunoderedzwa nekuda kwekubuda uye hydration paunenge uchidhinda chikamu chepamusoro, saka Kubatana pakati pezvikamu zvepasi kwakasimba.
1.4Mhedzisiro yeHPMC paMicromorphology ye3D Printing Mortar
Mifananidzo yeSEM yeM-H0 neM-H0.20 yemhando ye3 d inoratidza kuti maburi epamusoro eM-H0.20 emuenzaniso anowedzera zvakanyanya mushure mekuwedzera 0.20% HPMC, uye saizi yepore yakakura kupfuura iyo boka risina chinhu.Izvi Kune rumwe rutivi, imhaka yekuti HPMC ine mhepo-inopinza mhedzisiro, iyo inosuma yunifomu uye yakanaka pores;kune rumwe rutivi, zvingave kuti kuwedzerwa kweHPMC kunowedzera viscosity ye slurry, nokudaro kuwedzera kubudiswa kwekudzivirira kwemhepo mukati me slurry.Kuwedzera kunogona kuva chikonzero chikuru chekuderera kwema mechanical properties yedhaka.Kupfupisa, kuitira kuti uve nechokwadi chekusimba kweiyo 3D yekudhinda dhaka, zvirimo zveHPMC hazvifanirwe kunge zvakakura (≤ 0.20%).
Mukupedzisa
(1) Hydroxypropyl methylcellulose HPMC inovandudza kudhindwa kwedhaka.Nekuwedzera kwezviri mukati meHPMC, iyo extrudability yedhaka inoderera asi ichine yakanaka extrudability, iyo stackability inovandudzwa, uye inodhindwa Iyo nguva yakawedzera.Izvo zvakasimbiswa nekudhinda kuti deformation yepasi pasi pedhaka inoderedzwa mushure mekuwedzera HPMC, uye iyo yepamusoro-pasi reshiyo ndeye 0.84 kana iyo HPMC yemukati iri 0.20%.
(2) HPMC inovandudza rheological zvimiro zve 3D yekudhinda dhaka.Nekuwedzera kwehuwandu hweHPMC, iyo inooneka viscosity, kushushikana kwegoho uye plastiki viscosity ye slurry inowedzera;thixotropy inotanga kuwedzera uyezve inoderera, uye kudhinda kunowanikwa.Kuvandudza.Kubva pakuona kwe rheology, kuwedzera HPMC kunogonawo kuvandudza kudhindwa kwedhaka.Mushure mekuwedzera HPMC, iyo slurry ichiri kuenderana neBingham rheological modhi, uye kunaka kweiyo fit R2≥0.99.
(3) Mushure mekuwedzera HPMC, iyo microstructure uye pores yezvinhu zvinowedzera.Zvinokurudzirwa kuti zvirimo zveHPMC zvisapfuure 0.20%, zvikasadaro zvichave nekukanganisa kukuru pamichina yedhaka.Simba rekubatanidza pakati pezvikamu zvakasiyana-siyana zve 3D kudhinda dhaka rakasiyana zvishoma, uye nhamba yezvikamu Kana iri pasi, simba rekubatana pakati pematope rinowedzera.
Nguva yekutumira: Sep-27-2022