Di wan dɛn we de mek klos we gɛt ay tɛmpracha na di teflɔn kin tɔk se fɔ rigul di rit we dɛn kin kɔl kol na di mɔs dairekt ɛn ifektiv we fɔ kɔntrol di kristaliniti. Afta PTFE dɔn kɔmplit wan mɛlt ɔp 380°C, mɔlikul chen dɛn de arenj insay kristal lɛtis we dɛn de pas tru di maksimal kristalizashɔn rit tɛmpracha rɛnj we na 310~315°C we dɛn de kol. di kol rεt de ditarεmin di kristal rijyכn prכpכshכn εn maykroskכpik mכfכlכji fכ di kכt.
1. Rapid kol (quenching) fɔ lɔw kristaliniti
Di sintered klos surface de kol kwik kwik wan via kol air curtains, cooling rollers ɔ normal-temperature wata tank. Di mɔlikul chen dɛn kin frɔz bifo dɛn arenj ɔltɛm ɛn ɔda wan, ɛn dɛn kin mek bɔku bɔku smɔl smɔl ɛn nɔ pafɛkt kristal gren dɛn. Di kotin we dɛn gɛt gɛt sɔft tɛkstɔr ɛn fayn fayn tafnɛs wit ɔptimayz nɔ-stik pefɔmɛns, we in hadnɛs ɛn wear rɛsistɛns de ridyus smɔl.
2. Slow kol (annealing) fɔ ay kristaliniti
Dɛn arenj wan ɔt prɛzɛvɛshɔn sɛkshɔn na di ɔlt fɔ di sinta ɔfna, ɔ dɛn kin kol di klos wit di ɔfna pan wan rili slo rit we na 10~50°C/h. dis de alaw fכ muv di mכlikul chen dεm fכ fכm big εn komplit sfεrulayt dεm. Di kotin bost ay hadnes, outstanding wear resistance ɛn stebul dimɛnshɔnal stebiliti, yet wit ridyus fleksibiliti ɛn inkris brittleness.
II. Ɔksijɛn Prɔses ɛn Matirial Kɔntrol
Na di besis fɔ kol rit rigyuleshɔn, di ɔgzilari mɛzhɔ dɛn we de kam biɛn kin fayn-tyun di kristaliniti fɔ PTFE kɔtin mɔ.
1. Sintering temperechur ɛn holdin tɛm
Di matirial fɔ ɔt to 380~400°C ɛn ol am fɔ inof tɛm fɔ mek i mɛlt di ɔrijinal kristal dɛn kɔmplit wan ɛn pul di tɛmral istri. Inadekwat sintering go lεf rεsidyual kristכl nyuklios, we go rεsult in εksyεsiv hכy εn כnεvεn distributed fainal kristaliniti.
2. Pɔst-tritmɛnt anilin
Fɔ kɔtin wit lɔw kristaliniti we dɛn kin gɛt bay we dɛn kin kol kwik kwik wan, sɛkɔndari kristal growth ɛn intanɛnt strɛs ɛliminɛshɔn kin riliys bay kɔnstant-tɛmpracha tritmɛnt na 300~320°C fɔ sɔm awa we dɛn kin fala wit slo kol, we kin mɔdaret inkrisayz di kɔtin kristaliniti.
3. Raw matirial mɔlikul wet
Ha-mכlikul-weyt PTFE dispershכn fכm hεy mεlt viskositi εn lכw mכlikul chen mobiliti, we de lid to wan slo kristכlayzeshn rεt. Ɔnda di sem kol kɔndishɔn, i izi fɔ pripia kɔtin dɛn we nɔ gɛt bɔku kristal.
4. Nyuklia ejen adishɔn
wan sכm sכm dכz (0.1%~1%) fכ inכgεnik filכ dεm כ pεrfluorinated kכpolimεr dεm kin gi big nכmba fכ hεtεrojεnik kristכl nyuklios εn sכmtεm rεfin kristכl gren dεm. Pan ɔl we i nɔ kin chenj di ɔl kristaliniti bad bad wan, i kin mek di kristal maykrostrɔkchɔ fayn fayn wan.
III. Komprehensiv Manejmɛnt fɔ Multi-Layer Kɔtin Prodakshɔn
Teflon ay-tεmpratura klos de prodyuz bay mכltipכl impregnashכn εn sintering prכsεs wit sכmtεm akumulet kכt, we nid tכgεt prכsεs kכntrכl lεk dis.
1. Intalayr kristalizashɔn kɔnsistɛns
difrεns we big pasmak pan di kol rεt bitwin layεr dεm go mek inkכnsistεnt intalayεr kristכliniti εn jεnarεt intanεt strεs, ivin lid to kכt pכl insay siriכs kes dεm. I rεkomεnd fכ adopt mild kol fכ intamεdiεt layεr dεm, εn impliment targeted rapid כ slo kul כnli fכ di כtamost layεr akɔdin to prodakshכn rikwaymεnt.
2. Kotin tiknɛs ifɛkt
Tik kotin dεm de sכfa frכm asynchronous kul bitwin di sכfa εn di insay layεr. di insay layt kin tεnd fכ fכm hכy kristaliniti biכs fכ di slo hεt disipεshכn. I nid fɔ ɛkstɛnd di sintering tɛm fayn fayn wan fɔ mek shɔ se yunifom tɛmpracha fɔ di ɔl kɔtin bifo dɛn impruv yunifayd kol prosidyuz.
3. Tɛnshɔn maching we yu de kol
di tεnshכn we dεn aplay pan di kכl sεf di tεm we di kul sεkshכn de afekt di כryenteshכn fכ mכlikul chen dεm, we de kכpl wit di kristכlayzeshn prכsεs εn jכyn de ditarεmin di fainal kristכl mכfכlכji εn dimεnshכnal stεbiliti. Kɔdinɛt ɛn prɛsis kɔntrol na sɔntin we pɔsin fɔ du.
IV. Kwantitaytiv Ditekshɔn fɔ Krɔstaliniti
Difrɛnshal Skan Kalorimɛtri (DSC) fɔ adopt fɔ chɛk kristaliniti afta prɔses ajɔstmɛnt. wan 5~10mg kכt sεmpl de hεt pan wan rεt 10°C/min fכ tεst di mεlt εntalpi. Di kristaliniti de kכl bay we dεn divayd di mεlt εntalpi we dεn tεst bay di tiori mεlt εntalpi fכ 100% kristalin PTFE (aprכksimatli 82J/g). Kɔmbayn wit bɛnd rɛsistɛns, wear rɛsistɛns ɛn ɔda pefɔmɛns tɛst dɛn, dɛn kin disayd di ɔptimal prɔses winda.
