Mkangano wa coefficient wa PTFE
The Friction Coefficient of PTFE Ndi Yaing'ono Kwambiri
Mkangano wa coefficient wa PTFE ndi yaying'ono kwambiri, 1/5 yokha ya polyethylene, yomwe ndi khalidwe lofunikira la pamwamba pa fluorocarbon. Chifukwa cha mphamvu zochepa kwambiri za intermolecular pakati pa mamolekyu a fluorine-carbon chain, PTFE ali ndi zinthu zopanda ndodo.
PTFE imakhala ndi makina abwino kwambiri pa kutentha kwakukulu kwa -196 mpaka 260 ℃, ndipo chimodzi mwazochita za ma polima a fluorocarbon ndikuti sakhala osasunthika pakatentha kwambiri.
PTFE ali ndi kachulukidwe kakang'ono ka 2.14-2.20g/cm3, pafupifupi osayamwa, ndipo ali ndi mlingo wofanana wa kuyamwa madzi osakwana 0.01%. PTFE ndi polima yofewa komanso yofooka, yokhala ndi mphamvu zazing'ono zowoneka bwino za intermolecular, kuuma kochepa, kuuma, ndi mphamvu, ndipo imapunduka pansi pa kupsinjika kwanthawi yayitali.
PTFE sachedwa kukwawa pansi katundu ndi mmene pulasitiki ndi ozizira otaya katundu. Kugwa kwa PTFE zimasiyanasiyana ndi kupsyinjika kosiyanasiyana, kutentha, ndi madigiri a crystallinity, ndikuwonjezeka ndi kutentha kwakukulu. Kugwa kwa PTFE ndi zosakwana 2% pamene mlingo wa crystallinity ali pakati pa 55% ndi 80%, ndipo amawonjezeka mofulumira pamene mlingo wa crystallinity ali pansipa 55% kapena pamwamba 80%.
The zabwino makina katundu wa PTFE ndiye kugundana kwake kochepa, komwe kuli pakati pa 0.01 ndi 0.10, kakang'ono kwambiri pakati pa zida zapulasitiki zomwe zilipo komanso zida zonse zauinjiniya.
Kupambana kwa PTFE kumawonjezeka ndi kuwonjezeka kutsetsereka liwiro, ndipo amakonda kukhazikika pamene liniya liwiro kufika 0.5-1.0m/s kapena apamwamba. The static friction coefficient of PTFE ndi yaying'ono kuposa dynamic friction coefficient. Kugwiritsa ntchito izi popanga zopangira kumatha kuchepetsa kukana koyambira ndikupangitsa kuti iziyenda bwino kuyambira koyambira mpaka kumapeto.
Mkangano wa coefficient wa PTFE amachepetsa ndi katundu wochuluka, ndipo amakhala osasinthasintha pamene katunduyo afika 0.8 MPa kapena apamwamba. Pansi pa liwiro lalitali komanso katundu wokwera, koyefit ya kukangana kwa PTFE ndi zosakwana 0.01. Mkangano wa coefficient wa PTFE imakhalabe yosasinthika kuchoka ku kutentha kotsika kwambiri kufika kumalo ake osungunuka, ndipo imangowonjezereka kwambiri pamene kutentha kwa pamwamba kuli kwakukulu kuposa malo osungunuka. Chifukwa yaing'ono intermolecular mphamvu wokongola, otsika kuuma PTFE, imavalidwa mosavuta ndi zipangizo zina. Komabe, malinga ngati kuuma kwapamwamba kwa zinthu zovala kuli koyenera, kuvala kwa PTFE akhoza kuchepetsedwa kwambiri.