Kana tepi yePTFE ichida kubvisa kupisa - semuenzaniso, kusungirira chikamu chesimba kune inopisa sink - iyo yekunamatira layer inofanira kuita zvinhu zviviri panguva imwe chete: kutamisa kupisa uye kubata zvakasimba. Kuwedzera thermally conductive fillers (alumina, boron nitride, etc.) inovandudza kupisa kwemafuta asi nguva dzose inoderedza kunamatira.
Dambudziko nderekuwedzera kupisa kupisa uku uchirasikirwa nekunamira kudiki sezvinobvira . Mhinduro iri mumatanho matatu ekuzadza: saizi yechidimbu, chimiro chechidimbu, uye kurodha muzana.
Aokai PTFE yakagadzira thermally conductive PTFE matepi emagetsi uye maindasitiri ekushandisa. Ichi chinyorwa chinotsanangura kuti saizi yechidimbu, morphology, uye kurodha zvinokanganisa sei kutengeserana, uye maitiro ekugadzira chiyero chepamusoro.
Particle Size - Iyo Yakanaka-Coarse Trade-Off
Particle saizi inotonga kuti mafirita anogadzira sei network inoitisa kupisa uye kuti inonamira inonyorovesa sei nzvimbo yekubatanidza.
1. Zvimedu zvakanaka (nano kune submicron)
Thermal effect: Yakakwirira nzvimbo inotungamira kune yakawanda particle-particle yekuonana mapoinzi, asiwo yakawedzera kupindirana kwemafuta ekupikisa (kuparadzira phonon). Yakakomba agglomeration inodzikamisa conductivity kunatsiridza.
Adhesion mhedzisiro: Fine zvimedu zvinotora hombe resin uye tackifiers, kuomesa inonamatira. Yekutanga tack inodonha zvakanyanya. Kuyerera kunoderera, kuderedza kunyorova pane yakaderera-pamusoro-simba PTFE substrates → yakaderera peel simba.
Mutongo: Kashoma kushandiswa chete. Ultra-yakanaka mafirita inopa marginal yekupisa kuwana asi inoparadza kunamatira.
2. Coarse particles (micron kusvika kumakumi emamicrons)
Thermal effect: Mashoma ekusangana mapoinzi asi akareba ega ega ekupisa maitirwo enzira. Kana yakanyatso kurongedzerwa pamwe neanonamira ukobvu gwara, inopa yakanaka kuburikidza-ndege conductivity.
Adhesion mhedzisiro: Yakadzika pasi nzvimbo inoshambadza shoma resin, kuchengetedza inonamira kupfava. Nekudaro, kana zvimedu zvakakora senge kana kukora kupfuura iyo inonamira layer (kazhinji 25-100 μm), inoomesa tepi pamusoro, inoderedza inobudirira yekubatanidza nzvimbo, uye kugadzira kushushikana pfungwa.
Mutongo: Inoshandiswa seyakanyanya conductive skeleton, asi inofanirwa kuve yakakura pazasi pekunamira ukobvu.
3. Mhinduro - bimodal blending
Sanganisa coarse uye akatsetseka zvimedu pane chaiwo ratios. Mbeu dzakatsetseka dzinozadza ma voids pakati pezvakakora zvimedu, zvichiwana kurongedza kwepedyo. Iine iyo yakafanana yakazara yakazara kurodha, bimodal giredhi inowedzera particle yekuonana mapoinzi (nani conductivity) kana, neimwe nzira, inosvika painotariswa conductivity ine shoma yakazara yakazara , ichisiya inoenderera mberi resin chikamu kuchengetedza kunamatira.
Kurudziro yeAokai PTFE : Kune 50 μm gobvu yekunamira layer, shandisa zvidimbu zvakakoshwa zve 20-30 μm zvakasanganiswa nezvidimbu zvakanaka zve 1-5 μm. Iyi nzira yebimodal ndiyo kiyi yekuenzanisa zvivakwa.
Particle Morphology - Shape Inobata Zvikuru
Non-spherical fillers anowirirana panguva yekuputira uye kuomesa, inokanganisa kuburikidza-ndege (Z-direction) thermal conductivity uye adhesion.
1. Spherical kana quasi-spherical fillers (semuenzaniso, spherical alumina)
Thermal effect: Isotropic. Zvimedu zvinonangana zviri nyore munzira yekukora, yakanaka kune-kupfuura-ndege kupisa kupisa.
Adhesion effect: Smooth surface haivharidzi resin kuyerera. Inochengetedza kutonhora-kuyerera uye pamusoro pemvura. Pakati pemaumbirwo ese pakuremerwa zvakaenzana, masipiramu anochengeta yakanakisa adhesion - kunyanya yekutanga tack.
Balance mukana: Yakanyanya kuenderana. Inokwirisa Z-axis yemafuta kuwana nekuderera kwekunamatira kurasikirwa.
2. Flaky fillers (semuenzaniso, boron nitride, graphene)
Thermal effect: High aspect ratio inopa yakanakisa mu-ndege conductivity, asi flakes anoenzanirana ne substrate, achipa zvishoma kuburikidza ne-ndege kuvandudzwa - kushata kwePTFE matepi anoda vertical kupisa kupisa.
Adhesion mhedzisiro: Mafurati anoita semafirimu ekuparadzanisa, achivharira kuyerera kwepurasitiki uye zvakanyanya kucheka tack yekutanga. Yakapinza mipendero inokonzeresa kusagadzikana, kuderedza peel simba.
Balance kusaipa: Kusakwana kweZ-direction yekudziya zvinodikanwa, zvinokanganisa zvakanyanya kunamira kwemukati. Hazvikurudzirwi sechinhu chikuru chekuzadza.
3. Fibrous kana zvisina kujairika fillers
Thermal effect: Yakakwira chikamu ratio inogona kuvaka conductive network pakurodha yakaderera.
Adhesion mhedzisiro: Kuwedzera adhesive viscosity, kuomesa PSA kuburikidza ne mechanic interlocking, uye kuparadza tackiness. Yakapinza mipendero inokuvadza inonamira-PTFE interface.
Mutongo: Kashoma kushandiswa seye main filler; kuwedzera kudiki chete sechinhu chebetsero chebhiriji.
Filler Loading - Kutsvaga iyo Percolation Inotapira Spot
Sezvo kurodha kwekuzadza kunowedzera, kupisa kwemafuta kunokwira zvishoma nezvishoma pakutanga, yobva yasvetuka zvakanyanya pachikumbaridzo chepercolation , ipapo mapani. Kunamatira, zvisinei, kunoderera nguva dzose.
1. Kurodha pasi (<30 vol%)
Mafirita zvitsuwa zvakasarudzika mune inoenderera resin matrix. Thermal conductivity zvishoma inovandudza. Kunamatira kunoramba kuri pedyo nePSA yakachena. Nzvimbo yakachengeteka yekuchengetedza tack, asi kuwana kwekupisa hakuna basa.
2. Medium-to-high loading (30-60 vol%) - hwindo rinokosha
Zvimedu zvinotanga kubata uye kugadzira nzira dzekufambisa. Thermal conductivity inokwira exponentially. Zvichakadaro, iyo inoenderera resin matrix inoparadzaniswa. Adhesive inoshanduka kuita brittle; kutanga tack uye svuura simba rinodonha zvakanyanya.
Iyi ndiyo optimization zone. Chinangwa ndechekushanda pamucheto wepasi pechikumbaridzo chepercolation - yakakwirira zvakakwana kuti isangane nemafuta ekupisa, yakaderera zvakakwana kuchengetedza inoenderera resin chikamu chekunamatira kunogamuchirwa.
3. Kukwidza kwepamusoro-soro (> 60 vol%)
Dense particle packing inononoka kuwedzera kuwedzera kwekupisa (plateau). Resin haigoni kuzadza mapeji ose; voids fomu. Adhesive inova yakaoma, brittle, uye inenge isiri-tacky. Iyo tepi inova isina kusimba inopisa firimu. Kusara kwepfuma kunorasika zvachose.
Special note yePTFE tepi (silicone PSA): Silicone ine yakaderera cohesion simba uye hurombo hunoenderana nekuzadza kupfuura acrylic. Iyo inoshivirira yakaderera yakanyanya filler kurodha. Kuzadza-kuzadza kunokonzeresa kunama pulverization.
Aokai PTFE empirical data : Kune spherical alumina musilicone PSA, iyo percolation chikumbaridzo ingangoita 35-45 vol%. Optimal chiyero chinowanikwa kutenderedza 40-45 vol% nekugovera bimodal. Pamusoro pe55 vol%, kunamatira kunova kusagamuchirwe kune mazhinji maapplication.
Kuti uwane yakagadzika thermal conduction-adhesion balance muPTFE yakakwirira-tembiricha yekunamatira matepi:
Shandisa spherical coarse particles (20-30 μm) seyokutanga conductive skeleton - inopa kuburikidza-ndege conductivity nekurasikirwa kudiki kwekunamatira.
Wedzera zvakanaka zvimedu (1-5 μm) kugadzira bimodal kugovera - inozadza voids, inoderedza yakazara yakazara inodiwa, inochengetedza resin matrix.
Chengetedza yakazara mafirita achirodha pazasi-yepakati renji yepercolation chikumbaridzo (yakatenderedza 40-45 vol% ye spherical alumina musilicone PSA).
Deredza mafiritsi kana fibrous fillers kusvika <5 wt% kana zvichidiwa zvachose - anokuvadza tack uye anopa zvishoma kuburikidza-ndege rubatsiro.
Mhedzisiro: A thermally conductive PSA tepi inonamatira uye inogara.
Aokai PTFE inogadzira matepi anopisa ePTFE achishandisa iyi bimodal spherical filler strategy. Isu tinokwanisa kugadzirisa thermal conductivity uye adhesion mazinga kune yako application.
Final Takeaway
Kuvandudza kupisa kwemafuta muPTFE adhesive matepi anogara achirwisana nekunamatira. Kukanganisa kwakanyanya kunobva kuspherical particles + bimodal size distribution + loading just past percolation . Dzivisa maflakes nemafiber kunze kwekunge application yako ichinyatsoda mu-ndege conductivity uye inogona kushivirira yakaderera tack.
Kune yepamusoro-inoshanda bonding nekupisa kupisa, thermally conductive PTFE tepi mhinduro yakasimbiswa. Bata Aokai PTFE kune maumbirwo anoenderana neako ekupisa uye peel zvinodiwa.
Zvemukati zvehunyanzvi zvinopihwa ne Jiangsu Aokai New Materials Technology Co., Ltd.
Kuti uwane ruzivo rwakadzama uye zvigadziriso zvetsika zvePTFE machira ekupisa, matepi, mabhandi emesh, nezvimwe:
Kuomerera kune hunyanzvi uye kutendeseka, isu tinopa imwe-yekumira yakagadziridzwa mhinduro uye anofunga mushure mekutengesa masevhisi.
