Babban hasara na fluoroelastomer (FKM) shine rashin juriyar ƙarancin zafin jiki. Matsakaicin zafin jiki mai ƙarancin zafi (TR10) na binary FKM shine gabaɗaya -18 zuwa -16 ℃, kuma yanayin canjin gilashin (Tg) shine -20 ℃; ƙarancin zafin jiki na ternary FKM ya fi talauci fiye da na FKM na binary. Nau'in ƙananan zafin jiki na musamman FKM yana da juriya mai ƙarancin zafi, amma farashin yana da yawa.
FKM a cikin ASTM D 2000-2012 'motoci roba kayayyakin misali tsarin rarrabawa' na M2, M5, M6 sa kayayyakin da ake bukata don wucewa da low-zazzabi embrittlement F15 (-25 ℃) gwajin, M4 sa kayayyakin da ake bukata don wucewa da low-zazzabi embrittlement F.17 (407) A cikin 'yan shekarun nan, ana buƙatar ƙarin samfuran FKM don biyan buƙatun duka juriya mai zafi (250-275 ℃) da ƙarancin zafin jiki F15 ko F17. Hanya mafi kyau ita ce a yi amfani da FKM mai ƙarancin zafin jiki, kamar gaɓoɓin zafin jiki na -45 ~ -40 ℃ Viton GLT nau'in FKM, amma wannan babban zafin jiki na FKM ba shi da kyau kuma farashin yana da wahala a sami karbuwar kasuwa. Ta hanyar inganta aikin haɗin gwiwar FKM na binary na iya saduwa da buƙatun ƙananan juriya da ƙananan zafin jiki, kuma farashin yana da ma'ana, ya zama wuri mai zafi na bincike.
Wannan takarda yana nazarin halayen FKM ƙananan zafin jiki na Tg, TR10 da zafin jiki (Tbri) na dangantaka tsakanin daliban digiri na biyu, masu cikawa, tsarin hadawa, da dai sauransu a kan binary da ternary FKM m ƙananan zafin jiki na ƙananan zafin jiki don shirye-shiryen ƙananan zafin jiki na FKM m don samar da tunani!
1. Halaye na FKM low-zazzabi embrittlement Properties
Rubber yana da nakasawa mai jujjuyawa, yana iya haifar da nakasa mai girma a ƙarƙashin aikin ƙaramin ƙarfi na waje, kuma ana iya dawo da shi yadda yake a asali bayan cire ƙarfin waje, don haka ana amfani da shi sosai. Sai dai yayin da zafin jiki ya ragu, a hankali elasticity na roba yana raguwa, kuma idan ya kai Tg, robar ya rasa elasticity kuma ya kasa. Saboda nau'ikan samfuran roba, a cikin aiwatar da amfani na iya haifar da tasiri, tashin hankali, juzu'i, torsion, extrusion, abrasion, da dai sauransu, ƙarancin ƙarancin zafinsa ya kamata ya dogara da yanayin aikin sa don zaɓar hanyar gwajin da ta dace. Hanyoyin gwajin ƙarancin zafin jiki waɗanda aka fi amfani da su sun haɗa da gwajin Tg, gwajin zafin jiki mai ƙarfi, gwajin ƙarancin zafin jiki, gwajin ƙarancin zafin jiki mai ƙarancin zafin jiki (gwajin Gimen), juriya ga ƙaddamarwa da gwajin ƙimar sanyi, gwajin ƙarancin zafin jiki, ƙarancin zafi matsawa nakasar dindindin da gwajin shakatawa na damuwa, da sauransu.
Ƙananan juriya na zafin jiki na FKM na iya kasancewa ta hanyar Tg, Tbri, TR10 da Torsion Temperature a ƙananan zafin jiki (TGem), da dai sauransu. Wadannan sigogi suna da ma'anoni daban-daban amma suna da dangantaka da juna.
(1) Tg shine yanayin zafin da robar ke canzawa daga yanayin da ke da ƙarfi sosai zuwa yanayin gilashi da yanayin gilashi zuwa yanayin elasticity mai ƙarfi, wanda yawanci ke bayyana motsin ƙananan ƙwayoyin sarƙoƙi na roba.
(2) Tbri shine zafin jiki wanda babu lalacewa ga roba a ƙarƙashin ƙayyadaddun yanayin tasiri na lalacewar ƙarfi, wanda yawanci yana nuna ƙarfin robar don amfani da ƙananan zafin jiki da kuma ikon iya jurewa lalacewa.
(3) Ana amfani da TR10 don kimanta tasirin viscoelasticity da crystallization na roba a ƙananan yanayin zafi, kuma yawanci yana nuna yanayin mafi ƙasƙanci wanda kayan roba zai iya kula da farfadowa na roba.
(4) TGem yana amfani da waya mai ƙwanƙwasa wanda aka sani akai akai a matsayin abin ishara don karkatar da samfurin a babban kusurwa, yayin da zafin jiki ya ragu, modul ɗin roba yana ƙaruwa, rashin ƙarfi yana ƙaruwa, kusurwar jujjuyawar yana raguwa har zuwa lokacin da yake jujjuyawa a Tg. Matsakaicin kusurwa na roba bisa ga canjin yanayin zafi zai iya kimanta ƙarancin zafinsa, yawanci yana nuna mafi ƙarancin zafin jiki wanda roba ke kula da elasticity.
2 FKM Tg, TR10 da dangantaka tsakanin Tbri
Mafi ƙarancin zafin jiki na FKM da aka fi amfani da shi shine Tg, TR10 da Tbri, mai siyarwa yawanci yana ɗaukar ma'aunin Tg da TR10, ASTM yana ɗaukar ma'aunin Tbri, akwai wasu bambance-bambance da alaƙa tsakanin waɗannan ukun.
2. 1 Alakar dake tsakanin Tg da TR10
TR10 na kowane sa na FKM yana kusa da Tg (bambancin bai wuce 3 ℃ ba), yana nuna cewa duka Tg da TR10 na iya yin nuni da ƙarancin zafin jiki da yanayin yanayin gilashin sarkar kwayoyin roba.
2.2 Dangantaka tsakanin abun ciki na FKM fluorine da kaddarorin ƙwanƙwasa ƙananan zafin jiki
A cikin binary na gama gari da na ternary FKM, TR10 yana ƙaruwa tare da haɓaka abun ciki na fluorine; lokacin da aka gabatar da monomer na huɗu, PMVE, abun ciki yana da babban tasiri akan TR10.
Abinda ke ciki yana da babban tasiri akan TR10. Ko da yake karuwar abun ciki na fluorine zai iya inganta girman iyakar FKM amfani da zafin jiki, amma a lokaci guda, saboda haɗin CF ya maye gurbin haɗin CH, rage laushi na sarkar kwayoyin halitta da ƙananan zafin jiki na roba.
2.3 Tasirin masu cikawa akan ƙarancin ƙarancin zafin jiki na mahaɗan FKM
Carbon baki N774 m yana da mafi ƙanƙanta Tbri da mafi ƙarancin zafi juriya; zinc oxide adhesive yana da mafi girman Tbri da mafi munin juriya mai ƙarancin zafi; Ƙarƙashin ƙarancin zafin jiki na nau'in nau'in mannewa guda biyar ba ya bambanta da yawa. Bayan nazarin, bayan ƙara daban-daban filaye, rata da tsari tsakanin sarƙoƙin ƙwayoyin cuta na FKM sun bambanta, kuma madaidaicin ƙarancin zafin jiki ya bambanta.
Bayan nazarin, bayan ƙara daban-daban fillers, rata da kuma tsarin tsakanin FKM kwayoyin sarƙoƙi ne daban-daban, da kuma m low-zazzabi embrittlement Properties ne daban-daban, da kuma filler tare da karamin adadin roba yana da ya fi girma gel abun ciki da kuma mafi low-zazzabi juriya.
2.4 Tasirin tsarin hadawa akan ƙarancin ƙarancin zafin jiki na mahaɗan FKM
Tsarin hadawa kuma yana da tasiri akan ƙarancin ƙarancin zafin jiki na mahadi FKM. Filastik kafin hadawa zai iya samun sassaucin kwayoyin roba mafi kyau
Ana iya inganta ƙarancin zafin jiki na fili ta hanyar yin filastik kafin haɗuwa. Maganin wucewa na bakin ciki bayan fakin fili na iya inganta kaddarorin tarwatsawa na filaye da masu daidaitawa, da haɓaka juriya mai ƙarancin zafi. Gabaɗaya magana, tsawon tsayin gyare-gyaren, yana rage ɗankowar Mooney na roba. Ƙara yawan lokutan gyare-gyare zai rage Tg na roba, amma al'amarin ba shi da mahimmanci, kuma babu wani gagarumin bambanci tsakanin Tg da Tbri na FKM tare da adadin lokuta daban-daban.
3 Kammalawa
(1) Tg na FKM yana kusa da na TR10, wanda zai iya nuna ƙananan zafin motsi na sarkar kwayoyin FKM da yanayin yanayin gilashi, kuma Tbri yana ƙasa da na Tg da TR10.
ƙasa da Tg da TR10.
(2) Ƙarƙashin ƙarancin zafin jiki na peroxide sulfurized high fluorine FKM ya fi kyau, kuma ƙarancin ƙarancin zafin jiki na bisphenol binary sulfurized FKM ya fi muni.
(3) FKM roba cike da carbon baki N774 yana da mafi ƙarancin zafi juriya; roba tare da ƙaramin adadin filler yana da babban abun ciki na gel kuma mafi kyawun juriya mai ƙarancin zafi.
(4) Yawan lokutan gyare-gyaren yana da ɗan tasiri akan ƙarancin ƙarancin zafin jiki na mahadi FKM.
