1.1Mmetụta nke HPMC na ibipụta ngwa ngwa obibi akwụkwọ 3D
1.1.1Mmetụta nke HPMC na extrudability nke 3D obibi ngwa agha
Ndị otu oghere M-H0 na-enweghị HPMC na ndị otu ule nwere ọdịnaya HPMC nke 0.05%, 0.10%, 0.20% na 0.30% kwere ka ha guzoro maka oge dị iche iche, wee nwalee mmiri mmiri. Enwere ike ịhụ na ntinye nke HPMC Ọ ga-ebelata mmiri mmiri nke ngwa agha; mgbe ọdịnaya nke HPMC ji nwayọọ nwayọọ na-abawanye site na 0% ruo 0.30%, mmalite mmiri nke ngwa agha na-ebelata site na 243 mm ruo 206, 191, 167, na 160 mm, n'otu n'otu. HPMC bụ polymer molekụla dị elu. Enwere ike jikọta ha na ibe ha iji mepụta usoro netwọk, na njikọta nke ciment slurry nwere ike ịba ụba site na ntinye ihe ndị dị ka Ca (OH) 2. Macroscopically, a na-eme ka njikọ nke ngwa agha dịkwuo mma. Site na ịgbatị oge nkwụsị, ogo hydration nke ngwa agha na-abawanye. mụbara, mmiri mmiri na-efunahụ oge. Mmiri nke otu oghere M-H0 na-enweghị HPMC belatara ngwa ngwa. N'ime otu nnwale na 0.05%, 0.10%, 0.20% na 0.30% HPMC, ogo nke mbelata nke mmiri na-ebelata ka oge na-aga, na mmiri mmiri nke ngwa agha mgbe ọ guzoro maka 60 min bụ 180, 177, 164, na 155 mm n'otu n'otu. . Mmiri mmiri bụ 87.3%, 92.7%, 98.2%, 96.8%. Incorporation nke HPMC nwere ike imeziwanye ikike njigide nke ngwa agha fluidity, nke bụ n'ihi nchikota nke HPMC na mmiri molekul; N'aka nke ọzọ, HPMC nwere ike ịmepụta ihe nkiri yiri nke ahụ Ọ nwere nhazi netwọk ma kechie ciment, nke na-ebelata ngbanwe nke mmiri na ngwa agha ma nwee ụfọdụ ọrụ njigide mmiri. Ọ dị mma ịmara na mgbe ọdịnaya nke HPMC bụ 0.20%, ikike njigide nke mmiri mmiri na-erute ọkwa kachasị elu.
The fluidity nke 3D obibi ngwa agha agwakọta na iche iche ichekwa nke HPMC bụ 160 ~ 206 mm. N'ihi na dị iche iche na ngwa nbipute parameters, akwadoro ranges nke fluidity nwetara dị iche iche na-eme nchọpụta dị iche iche, dị ka 150 ~ 190 mm, 160 ~ 170 mm. Site na eserese 3, enwere ike ịhụ ya nke ọma Ọ nwere ike ịhụ na mmiri mmiri nke ngwa ngwa mbipụta 3D jikọtara ya na HPMC na-abụkarị n'ime oke akwadoro, ọkachasị mgbe ọdịnaya HPMC bụ 0.20%, mmiri nke ngwa agha ahụ n'ime nkeji 60 dị n'ime. nso nso a na-atụ aro, nke na-emeju mmiri mmiri kwesịrị ekwesị na stackability. Ya mere, ọ bụ ezie na mmiri mmiri nke ngwa agha nwere oke kwesịrị ekwesị nke HPMC na-ebelata, nke na-eduga na mbelata nke extrudability, ọ ka nwere ezigbo extrudability, nke dị n'ime oke akwadoro.
1.1.2Mmetụta nke HPMC na stackability nke 3D obibi ngwa agha
N'ihe banyere ejighị ihe ndebiri, nha nha nha nha n'okpuru ibu onwe ya na-adabere na nrụgide mkpụrụ nke ihe ahụ, nke metụtara njikọ dị n'ime n'etiti slurry na mkpokọta. Enyere njigide ọdịdị nke ngwa ngwa obibi 3D nwere ọdịnaya HPMC dị iche iche. Ọnụego mgbanwe na oge guzoro. Mgbe agbakwunyere HPMC, a na-eme ka ọnụọgụ njide nke ngwa agha dịkwuo mma, ọkachasị na mbido mbụ ma guzoro maka nkeji 20. Otú ọ dị, site n'ịgbatị oge eguzo, mmụba nke HPMC n'ụdị njigide nke ngwa agha ji nwayọọ nwayọọ na-ebelata, nke bụ n'ihi na ọnụ ọgụgụ njide na-abawanye nke ukwuu. Mgbe i guzoro maka nkeji 60, naanị 0.20% na 0.30% HPMC nwere ike melite ogo njigide nke ngwa agha.
The penetration resistance test results of the penetration resistance test results of the 3D printing mortar with different HPMC contents are gosiri na Figure 5. Enwere ike ịhụ site na Figure 5 na penetration eguzogide n'ozuzu na-abawanye na ndọtị nke guzo oge, nke bụ tumadi n'ihi na eruba nke slurry n'oge usoro hydration ciment. O ji nwayọọ nwayọọ malite ghọọ ihe siri ike; na nkeji 80 nke mbụ, ntinye nke HPMC mụbara nguzogide ntinye, yana mmụba nke ọdịnaya nke HPMC, nguzogide ntinye abawanyela. The ukwuu penetration eguzogide, deformation nke ihe n'ihi na etinyere ibu Ka ukwuu na-eguzogide HPMC bụ, nke na-egosi na HPMC nwere ike melite mmalite stackability nke 3D obibi ngwa agha. Ebe ọ bụ na a na-ejikọta hydroxyl na ether agbụ na polymer yinye nke HPMC ngwa ngwa na mmiri site hydrogen agbụ, na-akpata na nwayọọ nwayọọ Mbelata nke free mmiri na njikọ n'etiti ahụ na-abawanye, esemokwu ike na-abawanye, otú n'oge penetration eguzogide ibu ibu. Mgbe o guzoro maka nkeji 80, n'ihi hydration nke ciment, ntinye ntinye nke otu oghere na-enweghị HPMC mụbara ngwa ngwa, ebe ntinye ntinye nke otu ule na HPMC mụbara Ọnụego agbanweghị nke ukwuu ruo ihe dị ka 160 min nke guzoro. Dị ka Chen et al., Nke a bụ tumadi n'ihi na HPMC na-emepụta ihe nkiri nchebe gburugburu akụkụ ciment, nke na-agbatị oge nhazi oge; Pourchez et al. conjectured na nke a bụ tumadi n'ihi eriri Simple ether mmebi ngwaahịa (dị ka carboxylates) ma ọ bụ methoxyl otu nwere ike igbu oge ciment hydration site retarding guzobe Ca (OH) 2. Ọ dị mma ịmara na, iji gbochie mmepe nke nguzogide ịbanye na-emetụta site na evaporation nke mmiri n'elu ihe atụ ahụ, a na-eme nnwale a n'okpuru otu ọnọdụ okpomọkụ na iru mmiri. N'ozuzu, HPMC nwere ike melite stackability nke ngwa agha ebipụta 3D na mbido mbụ, na-egbu oge coagulation, na ịgbatị oge a na-ebi akwụkwọ nke ngwa ngwa obibi 3D.
Ihe eji ebi akwụkwọ 3D (ogologo 200 mm × obosara 20 mm × oyi akwa 8 mm): Otu oghere na-enweghị HPMC nwere nkwarụ siri ike, daa ma nwee nsogbu ọbara ọgbụgba mgbe a na-ebipụta oyi akwa nke asaa; Ngwa agha otu M-H0.20 nwere ezigbo stackability. Mgbe ebipụta 13 n'ígwé, elu ọnụ obosara bụ 16.58 mm, ala nsọ obosara bụ 19.65 mm, na elu-na-ala ruru (oke nke elu ọnụ obosara na ala nsọ obosara) bụ 0.84. Ntugharị akụkụ dị ntakịrị. Ya mere, a kwadoro ya site na ibipụta na ntinye nke HPMC nwere ike imeziwanye mbipụta nke ngwa agha. Mortar fluidity nwere ezi extrudability na stackability na 160 ~ 170 mm; Ọnụego njide ọdịdị erughị 70% nwere nnukwu nrụrụ ma enweghị ike irute ihe achọrọ nbipụta.
1.2Mmetụta nke HPMC na rheological Njirimara nke 3D obibi ngwa agha
A na-enye viscosity pụtara ìhè nke pulp dị ọcha n'okpuru ọdịnaya HPMC dị iche iche: na mmụba nke ọnụ ọgụgụ shear, viscosity pụtara ìhè nke pulp dị ọcha na-ebelata, na ihe na-eme ka shear thinning dị n'okpuru nnukwu ọdịnaya HPMC. O doro anya karịa. The HPMC molecular yinye bụ nsogbu na-egosi elu viscosity na obere shiee ọnụ ọgụgụ; ma na ọnụ ọgụgụ dị elu, ụmụ irighiri ihe HPMC na-aga n'otu n'otu na n'usoro n'usoro n'usoro nke shear, na-eme ka ụmụ irighiri ihe dị mfe ịfefe, ya mere, okpokoro ahụ pụtara viscosity nke slurry dị ntakịrị. Mgbe ọnụ ọgụgụ shear karịrị 5.0 s-1, viscosity pụtara ìhè nke P-H0 na otu oghere na-akwụsi ike n'ime 5 Pa s; ebe viscosity pụtara ìhè nke slurry na-abawanye mgbe agbakwunyere HPMC, yana agwakọta ya na HPMC. Mgbakwunye nke HPMC na-abawanye esemokwu dị n'ime n'etiti akụkụ ciment, nke na-eme ka viscosity pụtara ìhè nke mado ahụ, na arụmọrụ macroscopic bụ na extrudability nke ngwa ngwa mbipụta 3D na-ebelata.
A na-edekọ mmekọrịta dị n'etiti nrụgide siri ike na ọnụ ọgụgụ dị ọcha nke slurry dị ọcha na nyocha rheological, na-eji ihe nlereanya Bingham mee ihe iji kwado nsonaazụ ya. E gosipụtara nsonaazụ ya na eserese 8 na tebụl 3. Mgbe ọdịnaya nke HPMC bụ 0.30%, ọnụ ọgụgụ shear n'oge ule ahụ karịrị 32.5 Mgbe viscosity nke slurry gafere oke nke ngwa na s-1, data kwekọrọ. enweghị ike ịnakọta isi. N'ozuzu, a na-eji mpaghara ebe mgbago na-ebili ma na-ada ada na ọkwa kwụsiri ike (10.0 ~ 50.0 s-1) jikọtara ya iji mara thixotropy nke slurry [21, 33]. Thixotropy na-ezo aka n'ihe onwunwe nke slurry nwere oke mmiri dị n'okpuru ọrụ ike nke mpụga, ma nwee ike ịlaghachi n'ọnọdụ mbụ ya mgbe a kagbuo ịkwa osisi. thixotropy kwesịrị ekwesị dị ezigbo mkpa maka mbipụta nke ngwa agha ahụ. Enwere ike ịhụ site na eserese 8 na mpaghara thixotropic nke otu oghere na-enweghị HPMC bụ naanị 116.55 Pa / s; mgbe agbakwunyere 0.10% nke HPMC, mpaghara thixotropic nke ntanetị ụgbụ ahụ mụbara nke ukwuu ruo 1 800.38 Pa / s; Site na mmụba nke , mpaghara thixotropic nke mado ahụ belatara, mana ọ ka dị okpukpu 10 karịa nke otu oghere. Site n'echiche nke thixotropy, ntinye nke HPMC mere ka ebipụta ngwa agha dịkwuo mma.
Iji mee ka ngwa agha ahụ nọgide na-enwe ọdịdị ya mgbe ọ nwụsịrị ma na-eguzogide ibu nke oyi akwa ahụ na-esote, ngwa agha ahụ kwesịrị inwe nrụgide mkpụrụ dị elu. Enwere ike ịhụ site na tebụl 3 na nrụgide mkpụrụ τ0 nke net slurry na-akawanye mma mgbe agbakwunyere HPMC, ọ dịkwa ka HPMC. A na-ejikọta ọdịnaya nke HPMC nke ọma; mgbe ọdịnaya nke HPMC bụ 0.10%, 0.20%, na 0.30%, nrụgide mkpụrụ nke ntanye net na-abawanye na 8.6, 23.7, na 31.8 ugboro nke otu oghere, n'otu n'otu; viscosity plastik μ na-abawanye na mmụba nke ọdịnaya nke HPMC. Mbipụta 3D chọrọ na viscosity rọba nke ngwa agha ekwesịghị ịdị ntakịrị, ma ọ bụghị ya, nrụrụ ahụ mgbe extrusion ga-adị ukwuu; n'otu oge ahụ, a ga-edobe viscosity plastik kwesịrị ekwesị iji hụ na nkwụsi ike nke extrusion ihe. Na nchịkọta, site n'echiche nke rheology, HPMC's Incorporation nwere mmetụta dị mma na nkwalite nke stackability nke 3D obibi ngwa agha. Mgbe itinyechara HPMC, tapawa dị ọcha ka dabara n'ụdị reological Bingham, na ịdị mma nke dabara R2 adịghị ala karịa 0.99.
1.3Mmetụta nke HPMC na akụrụngwa akụrụngwa nke ngwa ngwa obibi akwụkwọ 3D
28 d ike mkpakọ na ike mgbanwe nke ngwa ngwa mbipụta 3D. Site na mmụba nke ọdịnaya HPMC, 28 d mkpakọ na ike mgbanwe nke ngwa ngwa mbipụta 3D belatara; mgbe ọdịnaya nke HPMC ruru 0.30%, ike mkpakọ 28 d na ike mgbanwe bụ 30.3 na 7.3 MPa, n'otu n'otu. Nnyocha egosiwo na HPMC nwere mmetụta ikuku na-eme ka ikuku dị, ma ọ bụrụ na ọdịnaya ya dị elu, porosity nke ime nke ngwa agha ga-abawanye nke ukwuu; Nguzogide mgbasa na-abawanye ma ọ na-esiri ike ịhapụ ihe niile. Ya mere, mmụba nke porosity nwere ike ịbụ ihe kpatara mbelata ike nke ngwa ngwa mbipụta 3D nke HPMC kpatara.
Usoro ịkpụzi lamination pụrụ iche nke mbipụta 3D na-eduga n'ịdị adị nke mpaghara na-adịghị ike na nhazi na ihe eji arụ ọrụ n'etiti akụkụ ndị dị n'akụkụ, na ike njikọta n'etiti akwa akwa nwere mmetụta dị ukwuu na ike niile nke akụrụngwa ebipụtara. Maka ụdị mpempe akwụkwọ 3D agwakọtara na 0.20% HPMC M-H0.20 ka ebibiri ike njikọ interlayer site na usoro nkewa interlayer. Ike njikọ interlayer nke akụkụ atọ dị elu karịa 1.3 MPa; na mgbe ọnụ ọgụgụ nke ọkwa dị ala, ike njikọ interlayer dị ntakịrị elu. Ihe kpatara ya nwere ike ịbụ na, n'otu aka ahụ, ike ndọda nke elu elu na-eme ka ọkpụkpụ dị ala na-ejikọta ya; N'aka nke ọzọ, elu nke ngwa agha ahụ nwere ike inwekwu mmiri mgbe ị na-ebipụta akwa oyi akwa, ebe mmiri mmiri nke mmiri na-ebelata n'ihi evaporation na hydration mgbe ị na-ebipụta akwa akwa elu, ya mere Njikọ dị n'etiti ala ala dị ike karị.
1.4Mmetụta HPMC na Micromorphology nke 3D Printing Mortar
Ihe onyonyo SEM nke ụdị M-H0 na M-H0.20 na afọ 3 na-egosi na oghere dị elu nke ụdị M-H0.20 na-abawanye nke ukwuu mgbe agbakwunyere 0.20% HPMC, na nha pore dị ukwuu karịa nke otu oghere. Nke a N'otu aka ahụ, ọ bụ n'ihi na HPMC nwere mmetụta ikuku ikuku, nke na-ewebata uwe na mma pores; N'aka nke ọzọ, ọ nwere ike ịbụ na mgbakwunye nke HPMC na-abawanye viscosity nke slurry, si otú ahụ na-abawanye nkwụsị nke ikuku n'ime slurry. Mmụba ahụ nwere ike ịbụ isi ihe kpatara mbelata akụrụngwa akụrụngwa nke ngwa agha ahụ. N'ịchịkọta, iji hụ na ike nke 3D ngwa ngwa obibi akwụkwọ, ọdịnaya nke HPMC ekwesịghị ịdị oke (≤ 0.20%).
Na ngwụcha
(1) Hydroxypropyl methylcellulose HPMC na-eme ka mbipụta nke ngwa agha dịkwuo mma. Na mmụba nke ọdịnaya nke HPMC, extrudability nke ngwa agha na-ebelata ma ka nwere ezi extrudability, na stackability na-mma, na-ebipụta The oge na-adịte aka. Achọpụtara ya site na ibipụta na nrụrụ nke oyi akwa nke ngwa agha na-ebelata ka agbakwunyere HPMC, yana oke elu-ala bụ 0.84 mgbe ọdịnaya HPMC bụ 0.20%.
(2) HPMC na-eme ka akụrụngwa obibi akwụkwọ 3D dịkwuo mma. Site na mmụba nke ọdịnaya HPMC, viscosity pụtara ìhè, na-enye nrụgide na viscosity plastik nke mmụba slurry; thixotropy na-ebu ụzọ na-abawanye wee na-ebelata, a na-enwetakwa mbipụta ahụ. Mmelite. Site n'echiche nke rheology, ịgbakwunye HPMC nwekwara ike melite printability nke ngwa agha. Mgbe ịgbakwunye HPMC, slurry ahụ ka na-agbaso usoro reological Bingham, yana ịdị mma nke dabara R2≥0.99.
(3) Mgbe ịgbakwunye HPMC, microstructure na pores nke ihe na-abawanye. A na-atụ aro na ọdịnaya nke HPMC ekwesịghị ịfe 0.20%, ma ọ bụghị ya, ọ ga-enwe mmetụta dị ukwuu na ihe eji arụ ọrụ nke ngwa agha. Ike njikọ dị n'etiti ọkwa dị iche iche nke mpempe akwụkwọ mpempe akwụkwọ 3D dịtụ iche, na ọnụ ọgụgụ nke akwa akwa Mgbe ọ dị ala, ike njikọ dị n'etiti akwa akwa akwa dị elu.
Oge nzipu: Sep-27-2022