Wannan labarin yana magana ne akan yadda ƙirar ƙirar ƙirar ƙirar Teflon mai zafi (PTFE) mai zafi mai zafi ta daidaita yanayin iska tare da rufi da kaddarorin da ba na sanda ba. Rikici mai mahimmanci: iyawar iska yana buƙatar buɗaɗɗen pores, yayin da rufi yana buƙatar yawa kuma rashin sanda yana buƙatar filaye masu santsi. Madaidaitan dabarun ƙira: sarrafa matsakaicin diamita na pore (0.1-2μm, da kyau <0.5μm) don hana narkewar shiga da kuma kula da ƙarancin wutar lantarki; sarrafa porosity a 50-70% (≈60% mafi kyau duka) cimma Gurley 20-100s / 100cc da ƙarfin dielectric ≥2kV don fim ɗin 0.13mm; Ɗauki tsarin pore na cibiyar sadarwar 3D mai girma-tortuosity (τ≈2.5-4) don murkushe tashoshi masu fitarwa kai tsaye; gina asymmetric gradient pore tsarin tare da m surface fata Layer (1-5μm) ga maras sanda / rufi da porous ciki don breathability; shafa super-oleophobic/hydrophobic saman bayan jiyya ba tare da toshewar pore ba.

Wannan labarin yana gabatar da fa'idodin PTFE high-zazzabi zane a matsayin babban zafin jiki tace kafofin watsa labarai. Ƙarfin maɓalli shida: Fitaccen juriya na zafin jiki (ci gaba da 260 ° C, kololuwa ~ 300 ° C), wuce PPS (190 ° C) da aramid (200 ° C); Matsanancin rashin ƙarfi na sinadarai a kan acid, alkalis, kaushi da oxidants, hydrolysis-resistant, outperforming aramid da P84 a cikin lalata flue gas; Mafi kyawun aikin tsaftace ƙura tare da ƙarancin ƙarancin ƙarfi na ƙasa wanda ke ba da damar kawar da kek ɗin ƙura mai sauƙi da ci gaba da raguwar matsa lamba; Kyakkyawan ingancin tacewa tare da girman pore 0.1-3μm yana ɗaukar sama da 99.99% na abubuwan PM2.5; Rashin ƙonewa tare da LOI sama da 95%, tare da zaɓuɓɓukan anti-a tsaye akwai; Babban ƙarfin injiniya daga ƙarfafa fiberglass, tare da tsararren PTFE fiber kafofin watsa labarai yana ba da sassauci da> 4 shekara sabis rayuwa. Kwatanta da kyau da PPS, aramid, Nomex, P84 da fiberglass tace kafofin watsa labarai a cikin zafin jiki, juriya na sinadarai, juriya na hydrolysis da aikin tsaftacewa.

Wannan labarin yana ba da mafita na tsari don hana ragowar mannewa da zubar jini lokacin amfani da tef mai zafi mai zafi na PTFE don kare yatsun gwal na PCB yayin taron SMT. Tushen bincike na tushen: ragowar yana faruwa daga gazawar haɗin gwiwa ko canja wuri na fuska; zubar jini yana fitowa daga digon danko da mannewa ambaliya karkashin zafi mai sake kwarara. Maganin mahimmanci shine zaɓin tef ɗin da ya dace: silicone PSA tare da ɗan gajeren lokaci ganiya ≥300 ° C, ci gaba da ≥260 ° C, jimlar kauri 0.08-0.13mm tare da bakin ciki high-cohesion m yadudduka, da anti-bleed / saura-free takardar shaida. Gudanar da matakai guda shida: tsaftacewa na farko tare da IPA; lamination na sifili tare da cikakken fitar da iska; ingantaccen bayanin yanayin sake kwarara tare da dumama mai laushi (<2°C/s); bawon sanyi a ƙasa 50 ° C a kusurwar 180 °; aiki nan da nan a cikin sa'o'i 24 da amfani guda ɗaya kawai; sarrafa gazawar tare da gogewar IPA da duban girman girman 40-50x. Don PCBs masu gefe biyu, maye gurbin da sabon tef kafin sarrafa gefe na biyu.

Wannan labarin yana ba da jagorar tsari akan hana wrinkles akan zane mai zafin jiki na PTFE yayin sintering. Wrinkles suna haifar da asali ta hanyar raguwar yanayin zafi mara daidaituwa da rashin daidaituwa. Magani suna rufe cikakken aikin aiki: sarrafa kayan albarkatun ƙasa (cikakken dewaxing / saitin zafi don kawar da damuwa na ciki); impregnation da bushewa (mafi yawa na bakin ciki coatings, m zafin jiki gradient, m drive rollers); sintering tanderu iko (1-3% overfeed don thermal shrinkage izni, rufaffiyar madauki micro-tashin hankali iko, transverse zafin jiki uniformity tsakanin ± 5 ° C, gradient preheating-sintering-sanyi kwana, iska-flotation tanderu a matsayin mafi kyau duka bayani, lankwasa yada rollers); sanyaya da saitin (hannun hankali sannu a hankali, kula da yadawa har zuwa kasa 100 ° C, cikakken sanyaya kafin iska); saka idanu akan layi tare da duban haske mai ƙarfi da sikanin infrared.

Wannan labarin yana nazarin yadda yashi ko matt gama jiyya ke shafar tsarin saman PTFE babban zane mai zafin jiki. Canje-canje na faruwa a cikin nau'i uku: Ƙwararren ilimin halitta yana canzawa daga santsin madubi-kamar zuwa ruɓaɓɓen rubutun gully tare da haɓaka ƙimar Ra/Rz sosai, ƙirƙirar ƙirar injina na 3D don haɗin gwiwa na gaba. Mutuncin rufa yana fuskantar haɗari: PTFE Layer thinning, yuwuwar fallasa na fiberglass substrate (wanda ke haifar da asarar kadarar da ba ta da itace, shigar danshi, da rage ƙarfin injina), da microcracks da tarkace.

Wannan labarin ya gabatar da cikakken asali tsari don impregnating fiberglass masana'anta da PTFE emulsion. Matakai bakwai masu mahimmanci: ① Pretreatment (dewaxing / dewaxing) a 350-400 ° C don cire ma'aunin ma'auni; ② Tsarin emulsion tare da 40-55% m abun ciki da surfactants don inganta wetting; ③ Ciwon ciki ta hanyar tsoma-matsi ko murfin ruwa na likita; ④ Drying a 100-150 ° C don cire ruwa a hankali kuma ya samar da fim din PTFE bushe; ⑤ Sintering a 360-390 ° C (har zuwa 400 ° C) don narke sassan PTFE a cikin fim mai ci gaba; ⑥ Multi-cycle impregnation-bushewa-sintering maimaita sau 2-4 don isa manufa kauri da guduro abun ciki (45-65%); ⑦ Bayan jiyya ciki har da maganin korona, gyaran fuska, iska da dubawa mai inganci. Mahimman abubuwan sarrafawa: cikakken dewaxing, cikakken emulsion wetting, bushewa a hankali, madaidaicin zafin jiki, da daidaiton sutura. Kayayyakin suna hidimar laminati masu ɗaure da tagulla, bel masu zafi mai zafi da kayan membrane na gine-gine.

Wannan labarin ya ƙunshi mahimman alamomin aiki don tef ɗin PTFE mai zafin jiki da aka yi amfani da shi a cikin suturar iska, jiyya mai zafi da makamantansu. Mahimman buƙatun sun bambanta da yawa daga amfani da yanayi: fitar da gas shine mafi mahimmanci (TML≤1%, CVCM≤0.1%; Aerospace/nauyin gani na buƙatar TML≤0.5%, CVCM≤0.01%); Dole ne a tabbatar da juriya na zafin jiki don duka PTFE substrate (260 ° C) da manne Layer; Ana buƙatar PSA na silicone mai ƙarancin gas mai tsafta musamman don hana kamuwa da siloxane; ikon riƙe da zafin jiki mai girma yana hana haɓakawa da ɗagawa; tsabta ba ya buƙatar zubar da fiber da ƙananan abun ciki na ionic; tef anti-static (resistance surface 10⁶-10⁹ Ω/sq) yana hana lalacewar ESD; Dole ne a kimanta juriya na plasma don matakan sputtering / PECVD; thermal shrinkage kasa 2% yana tabbatar da daidaiton abin rufe fuska.

Wannan labarin yana gabatar da kaushi na halitta wanda PTFE babban zafin jiki na zane zai iya jurewa. Gilashin fiberglass mai rufaffiyar PTFE yana baje kolin inertness na musamman, yana tsayayya da kusan duk abubuwan kaushi na yau da kullun a ƙarƙashin yanayin aiki na yau da kullun ba tare da narke, kumburi ko halayen sinadaran ba. Abubuwan da za a iya jurewa sun hada da: alcohols (methanol, ethanol, isopropanol), ketones (acetone, MEK, cyclohexanone), esters (ethyl acetate, butyl acetate), hydrocarbons (man fetur, toluene, xylene, hexane), halogenated hydrocarbons (dichloromethane, chloroform, carbon ethers acid tetras, chloroform, chloride ethers tetras). (glacial acetic acid, formic acid), amines da amides (triethylamine, DMF), phenols, da sauransu kamar carbon disulfide, pyridine, silicone man da birki ruwa.

Wannan labarin ya ƙunshi buƙatun sanyaya lokacin PTFE babban zafin jiki na zane sintering. Bayan dasa shuki a 380-400 ° C, masana'anta dole ne su wuce da sauri ta yankin 310-315 ° C crystallization-m. Adadin sanyaya da aka ba da shawarar shine aƙalla 30-50°C/min (tufafin bakin ciki zai iya cimma 100-200°C/min ta hanyar sanyaya iska). Saurin sanyaya (quenching) yana haifar da ƙarancin crystallinity (45-50%), yana ba da taushi, sutura masu tauri tare da filaye masu santsi, mannewa mai ƙarfi, kyakkyawan aiki mara ƙarfi, da juriya ga delamination da fatattaka. Jinkirin sanyaya (sanyiwar tanderu) yana haifar da babban crystallinity (60-70%), yana haifar da tsattsauran ra'ayi, gaɓoɓin sutura masu saurin raguwa, kwasfa da microcracks.

Wannan labarin yana kwatanta yanayin ɗaki da zafin jiki mai girma na mannen matsi na silicone don tef ɗin PTFE. Babban zafin jiki balagagge (120-180 ° C) yana haifar da manyan hanyoyin sadarwa masu haɗin gwiwa tare da ƙarfin haɗin kai mai ƙarfi, yana hana ragowar mannewa bayan kwasfa. Yana samar da haɗin haɗin sinadarai tare da PTFE substrates ta hanyar haɗin gwiwa na farko, yana kawar da haɗarin lalata. Babban zafin jiki balagagge kuma yana kawar da ƙananan ƙananan ƙwayoyin cuta kafin bayarwa, yana hana kumburi da gurɓataccen mai na silicone yayin dumama na farko.