Vanodiwa mainjiniya, vadyidzani vekutenga, nevagadziri vesarudzo-
Mukubvunzana kwedu kwezuva nezuva kwehunyanzvi, mubvunzo watinowanzo bvunzwa hausi "Mutengo chii?" asi kuti, "Mutsetse uyu wokuisa chisimbiso uchagara kwenguva yakareba sei?"
Vatengi vakawanda vakasangana nenyaya inotevera: muenzaniso unoratidza kuiswa chisimbiso kwakakodzera panguva yekuedzwa, asi inotanga kubuda mvura kana mhepo mushure memwedzi mitatu yekushanda; kana, kunyangwe kuomarara kunosangana nezvinodiwa zvakatarwa, indentations isingadzokeri inocherechedzwa pane disassembly. Mhedzisiro yezviitiko izvi zvese zviri mune yakakosha pfuma muindasitiri yerabha - Compression Set (CS).
Nhasi, tichafamba kupfuura pfungwa dzisinganzwisisiki uye, kutanga kubva kumaketani emamorekuru uye chimiro chepore, tinopwanya misimboti inotaridza kuisa chisimbiso.
I. Kushanyirazve "Compressive Permanent Deformation"
Mumunda wesilicone yakaputirwa, iyo yekuisa chisimbiso yakaenzana nekuoma; iyo yekuisa chisimbiso zvakare yakaenzana nekugona kuramba compressive deformation.
Compressive zvachose deformation inoreva kuwanda kweiyo deformation iyo yakajairwa bvunzo specimen haigone kudzoserwa mushure mekuburitsa, kana sampuli yakatsikirirwa pamwero wakati (semuenzaniso, 25% kana 50%) pane yakatarwa tembiricha (semuenzaniso, 100 degree) kwenguva yakatarwa (semuenzaniso, 22 h kana 72 h). Kukosha kudiki kweiyi parameter inoratidza yakakwira elastic yekuchengeta chiyero chechinhu uye njodzi yakaderera yekudonha.
Kana imwe nguva yakakosha deformation inoitika, inoratidza:
Interface stress relaxation: Iyo clamping force pa flange connection inodzikira uye inowira pasi pemukati mepakati pressure.
Microchannel formation: kuputika kwepore kana kuputsika, zvichikonzera kupindirana kwekudonha nzira.
Kakawanda kugadzirisa: Mabhoti anofanira kusimbiswa nguva dzose kuti atsigire kurasikirwa kwekunetseka.
II. Iwo mana Makuru Zviyero Anosarudza Deformational Fate
Kupesvedzera kwekumanikidza deformation hakusi nekuda kwechinhu chimwe chete, asi kunomiririra yakaoma "systematic engineering" maitiro. Isu takaisa maitiro aya kuita nhanho ina dzakasiyana, kubva kune microscopic kusvika kune macroscopic scale:
1. Material Gene: The Game Dynamics of Formulation Systems
Ichi ndicho chikonzero chemukati che deformation, yakatemwa nesilicone raw rubber uye yekuwedzera system.
Raw rubber (base polymer) kusarudzwa: Iyo vinyl yemukati uye mamorekuru kugovera huremu zvinopesvedzera kuchinjika density. Raw rabha ine yakanyanyisa high viscosity inoratidza yakakomba molecular chain entanglement, zvichiita kuti zviome kuti cheni dzitsvedze panguva yekumanikidza; somugumisiro, deformation zvachose kazhinji kuwandisa.
Reinforcement uye crosslinking system: Kune "yegoridhe inflection point" muyero yevamiririri vevulcanizing. Kunyangwe kuwanda kweiyo vulcanizing mumiriri kunowedzera kuomarara, kunogona kuita kuti macheni anyanya kuomarara uye kuderedza kuchinjika kwawo, nekudaro zvichikanganisa kuomesa kuneta kuramba.
Foaming agent inoenderana: Huwandu hwekupupa hunofanirwa kuwiriraniswa nechiyero chevulcanization. Kana kupupa kuchiitika nekukasira pasina kuchinjika-kwakakwana, madziro ebubble anonyanyotetepa uye achatsemuka pakarepo pakudzvanyirirwa; kana kuyambuka-kubatanidza kukaitika nekukasira uku kubuda furo kunonokerwa, mabubbles haazokwanisi kukura zvizere, zvichikonzera kusakwana kuvharika-mwero wesero.
2. Microstructure: Yakavharwa-chikamu chepore volume uye pore size distribution
Iyi ndiyo nzvimbo yakakosha yekurwira umo silicone yakapupuma inosiyana kubva kune yakasimba silicone.
Ideal state: yunifomu, yakanaka-chimiro chehuchi chine chiyero chepamusoro chakavharika-sero. Kana yakamanikidzwa, gasi riri mukati memasero akavharwa rinoteerera mutemo waBoyle (P₁V₁=P₂V₂), ichipa rubatsiro rwepneumatic runoita kuti kukurumidza kudzorerwa kwemasero pakusunungurwa kwekumanikidzwa.
Yakaremara pores: Kana saizi yepore isina kuenzana (yakavharwa kana yakavhurika pores iripo), iyo compression stress ichave yakanamirwa pane yakakura pores. Kana mapoinzi aya asina kusimba kana kuputika kwepurasitiki, kudzvanya kuri kuita kwesealing cross-chikamu kucharasika zvachose.
3. Mamiriro ekushanda: Thermal nemedia-inokonzeresa kuchembera
Ichi ndicho chikonzero chekunze uye chikonzero chikuru chiri seri kwezviitiko zvakawanda pa-saiti yekukundikana.
Thermal-oxidative kuchembera: Tembiricha yepamusoro inomhanyisa kutsemuka kweoxidative yesilicone polymer backbone. Nekufamba kwenguva, zvinhu zvemukati zvinoomesa, uye muchinjiko wemukati-unobatanidza density inoshanduka, zvichiita kuti kuwedzere kudzoreredzwa kwekushushikana. Pa 150 dhigirii, iyo deformation mwero weyakajairwa silicone inogona kuita 3-5 nguva inoonekwa pane tembiricha.
Compression ratio setting: It is generally recommended that the compression ratio be between 15% and 25%. An excessively high compression ratio (>30%) ichapwanya zvakananga maseru pores, zvichikonzera kukuvara kwemuviri kusingachinji; yakawandisa yakaderera compression reshiyo ichatadza kumisa inoshanda yekutanga chisimbiso reshiyo kumanikidza.
4. Kukuvadza nzira: Kukundikana kwemuviri panguva yekumanikidza
Pasi pemaikorosikopu, kutadza kwekumanikidza kunowanzobatanidza matanho matatu:
Phase I (Gasi Escape): Kamwe-kamwe dzvinyiriro inowedzera inomanikidza gasi mukati megomba rakavharwa kuti ripukunyuke kuburikidza nemamicropores ari mububble wall.
Phase II (Bubble Wall Folding): Rusvingo rwebubble, rwakanangana negwara rekumanikidza, rinogadzira zvimiro zvechigarire pasi pesimba rekugera.
Phase III (Bubble wall rupture): The bubble wall, oriented perpendicular to compression direction, inoputika nekuda kwekunyanya kutambanudza; padyo nemabubble cavities anobva abatana, kugadzira macroscopic crack.
III. Nhungamiro Yekunzvenga Misungo Yakajairika Pakusarudza Zvigadzirwa
Semushandisi, isu hatikurudzire kuti vatengi vatarise chete pa "values" yakanyorwa mumushumo webvunzo; pane kudaro, vanofanira kubhadhara kune "values pasi pemamiriro chaiwo ekushanda." Heano mazano matatu anoshanda:
Kumbira "post-kuchembera" data, pane "yekutanga kuongorora" data.
Ndokumbira utarise kune iyo compression yekusingaperi deformation data yakawanikwa mushure mekuchembera pa150 dhigirii ye72 h kana pa225 dhigirii ye24 h, sekupihwa neanopa. Kuita kwakanaka pakudziya kwekamuri hakuvimbisi kugadzikana patembiricha yakakwirira.
Ongorora "stress relaxation" curve
Compressive permanent deformation i static phenomenon, ukuwo stress relaxation inzira ine simba. Kana mamiriro ezvinhu achibvumidza, mutengesi anofanirwa kukumbirwa kuti ape curve inoratidza kuti simba rinoshandiswa rinoora sei nekufamba kwenguva panguva yakatarwa yekumanikidza. Mutsetse munyoro unoratidza hupenyu hwesevhisi hurefu.
Kutora kuomarara uye density kubva mumamiriro ekushanda:
Kudzikira{{0}kudzvanywa, kuvharika kwakadzikama (semuenzaniso, kudzivirira huruva kune zvigadziriso zvemwenje): Kudzikira-kuomarara, kukwirisa-zvinhu zvinodzosera kumashure (density 0.35–0.45 g/cm³) zvinogona kusarudzwa.
Yakakwira{{0}kudzvanya, kuvharika maapplications (eg, magetsi mabhatiri packs): Zvinokurudzirwa kushandisa zvinhu zvine zviripakati nepakati-ku{4}}kuomarara kwakanyanya uye kuvharika kwakanyanya-sero rezinga (density: 0.5–0.7 g/cm³), uye kuisa magadzirirwo akakodzera embabvu.
Semutengesi ane mukurumbira wekuChina muindasitiri yefoam silicone, kukosha kwedu kunodarika kungoendesa mupumburu wemachira ekuisa chisimbiso; zviri mukukupa "gadziriso{{0}yemahara" yekuisa chisimbiso mukati mehupenyu hwese - inowanikwa kuburikidza nemazvo magadzirirwo ekugadzirisa (optimizing cross-linking/foaming copatibility) uye kwakasimba kudzora maitiro (kuve nechokwadi chechimiro chakafanana chepore).
Kana uchitsvaga zvekuvharisa zvinoenderana nemamiriro ekushanda chaiwo-sekunyanya kudziya-kuderera kwe tembiricha, intense ultraviolet mwaranzi, kana high-frequency vibration-ndapota sunungukai kutibata chero nguva. Tinogona kukupa data yakagadziridzwa yekufembera inoenderana nereshiyo yako chaiyo yekuminyanisa uye tembiricha zvinodiwa, tichikubatsira kurerutsa magadzirirwo-njodzi dzinoenderana nedata-zvinofambiswa neruzivo.