Khohlano ea khohlano ea PTFE
The Friction Coefficient of PTFE e Nyane Haholo
Khohlano ea khohlano ea PTFE e nyane haholo, ke 1/5 feela ea polyethylene, e leng tšobotsi ea bohlokoa ea bokaholimo ba fluorocarbon. Ka lebaka la matla a tlase haholo a li-intermolecular lipakeng tsa limolek'hule tsa ketane ea fluorine-carbon, PTFE e na le litšobotsi tse se nang thupa.
PTFE e boloka thepa e babatsehang ea mochine holim'a mocheso o pharaletseng oa -196 ho isa ho 260 ℃, 'me e' ngoe ea litšobotsi tsa li-polymers tsa fluorocarbon ke hore ha li fetohe brittle mocheso o tlase.
PTFE e na le sekhahla se phahameng sa 2.14-2.20g/cm3, e batla e sa monye, 'me e na le sekhahla se lekanang sa ho monya metsi se ka tlase ho 0.01%. PTFE ke polima e tloaelehileng e bonolo le e fokolang, e nang le matla a manyenyane a khahlehang a li-intermolecular, ho satalla ho fokolang, ho thatafala, le matla, 'me e tla holofala tlas'a khatello ea nako e telele.
PTFE e na le tšekamelo ea ho kena tlas'a mojaro 'me ke polasetiki e tloaelehileng e nang le thepa ea ho phalla ha serame. The creep of PTFE e fapana ka likhatello tse fapaneng tsa khatello, mocheso, le likhato tsa crystallinity, 'me e eketseha ka mocheso o ntseng o eketseha. The creep of PTFE e ka tlase ho 2% ha tekanyo ea crystallinity e pakeng tsa 55% le 80%, 'me e eketseha ka potlako ha tekanyo ea crystallinity e ka tlase ho 55% kapa ka holimo ho 80%.
Thepa e babatsehang ea mechine ea PTFE ke coefficient ea eona e nyane ea likhohlano, e lipakeng tsa 0.01 le 0.10, e nyane ho fetisisa har'a lisebelisoa tsa polasetiki tse teng esita le lisebelisoa tsohle tsa boenjiniere.
Khohlano ea PTFE e eketseha ka lebelo le ntseng le eketseha la ho thella, 'me e atisa ho tsitsa ha lebelo la mola le fihla ho 0.5-1.0m/s kapa ho feta. The static friction coefficient of PTFE e nyane hofeta coefficient e matla ea khohlano. Ho sebelisa tšobotsi ena ho hlahisa tlhahiso ho ka fokotsa khanyetso ea ho qala le ho etsa hore e tsamaee hantle ho tloha qalong ho fihlela qetellong.
Khohlano ea khohlano ea PTFE e fokotseha ka mojaro o ntseng o eketseha, 'me e atisa ho lula e le teng ha mojaro o fihla ho 0.8 MPa kapa ho feta. Tlas'a lebelo le phahameng le mojaro o phahameng, coefficient ea khohlano ea PTFE e ka tlase ho 0.01. Khohlano ea khohlano ea PTFE e lula e batla e sa fetohe ho tloha ho mocheso o tlase haholo ho ea sebakeng sa eona sa ho qhibiliha, 'me e eketseha haholo ha mocheso o holim'a metsi o phahame ho feta ntlha ea ho qhibiliha. Ka lebaka la matla a manyenyane a khahlehang a intermolecular, boima bo tlase ba PTFE, e aparoa habonolo ke lisebelisoa tse ling. Leha ho le joalo, hafeela bokhabane bo ka holimo ba thepa ea ho roala bo loketse, ho roala ha PTFE e ka fokotsoa haholo.