1. Ana nuna tasirin Cl-on corrosion ƙarfe ta fuskoki biyu: ɗaya shine rage yuwuwar ƙirƙirar fim ɗin wucewa a saman kayan ko don hanzarta lalata fim ɗin wucewa, ta hakan yana haɓaka lalata gida; a gefe guda, yana rage solubility na CO2 a cikin maganin ruwa. , Don saukaka lalata kayan.
Cl- yana da halayen ƙaramin radius na ion, ƙarfin shiga mai ƙarfi, da ƙarfin talla ta saman ƙarfe. Mafi girman maida hankali na Cl-, yana ƙaruwa da ƙarfin isasshen ruwan mai ruwa da ƙananan juriya na electrolyte. Ya fi sauƙi ga Cl- ya isa saman ƙarfe kuma ya hanzarta aiwatar da lalatawar gida; kasancewar Cl- a cikin yanayin acidic zai samar da sinadarin chlorides a saman ƙarfe Gishirin Gishiri, kuma ya maye gurbin fim ɗin FeCO3 tare da kaddarorin kariya, wanda ke haifar da ƙima mai yawa. A lokacin aikin lalata, Clˉ ba wai yana tarawa a cikin ramuka ne kawai ba, har ma yana taruwa a wuraren da ba a samar da ramin ramukan ba. Wannan na iya zama farkon tsarin ramin rami. Yana nuna cewa tsarin wutar lantarki mai ninki biyu a keɓancewa tsakanin baƙin ƙarfe na matrix da fim ɗin samfuran lalata yana da sauƙi don fifita tallan Clˉ, wanda ke sa maida hankali na Clˉ a ƙirar ke ƙaruwa. A wasu yankuna, Clˉ zai tara kuma ya zama nuclei, wanda zai haifar da rushewar anodic a cikin wannan yanki. Ta wannan hanyar, matrix na ƙarfe zai lalace ta hanyar zurfafa zurfafa ƙasa, yana haifar da ramuka. Rushewar ƙarfe na anode zai hanzarta watsa Clˉ ta hanyar fim ɗin samfuran lalata a cikin ramin rami, kuma ya ƙara haɓaka Clˉ a cikin ramin rami. Wannan tsari nasa ne na Clˉ Injin da ake kira catalytic shine lokacin da taro na Clˉ ya wuce wani ƙima mai mahimmanci, ƙarfe anode koyaushe zai kasance cikin yanayin aiki kuma ba za a wuce shi ba. Sabili da haka, a ƙarƙashin tasirin Clˉ, ramin ramin zai ci gaba da faɗaɗa da zurfafa. Kodayake abun Na a cikin maganin yana da inganci, nazarin bakan makamashin fim ɗin samfurin lalata bai sami wanzuwar Na kashi ba, yana nuna cewa fim ɗin lalata yana da taka rawa a cikin rarraba cations zuwa jagorancin ƙarfe; yayin da anion yana da sauƙin shiga. Fim ɗin samfuran da aka lalata yana kaiwa ga keɓancewa tsakanin substrate da fim. Wannan yana nuna cewa fim ɗin samfurin lalata yana da zaɓin ion, wanda ke haifar da ƙaruwa cikin haɓakar anion a ke dubawa.
2. Karɓar bakin ƙarfe na austenitic ta ions chloride galibi yana haifar da ɓarna.
Injiniya: Ana sauƙaƙe ions na chloride akan fim ɗin wucewa, yana fitar da iskar oxygen, sannan a haɗa tare da cations a cikin fim ɗin wucewa don ƙirƙirar chlorides masu narkewa. A sakamakon haka, ƙaramin rami ya lalace a ƙarfe na jikin da aka fallasa. Waɗannan ƙananan ramuka ana kiransu pitting nuclei. Waɗannan chlorides ana sauƙaƙe su da hydrolyzed, ta yadda ƙimar pH na maganin a cikin ƙaramin rami zai faɗi, kuma maganin zai zama mai guba, yana narkar da wani fim na oxide, wanda ke haifar da ions ƙarfe mai yawa. Domin lalata tsaka tsakin wutar lantarki a cikin rami, Ƙungiyoyin waje suna ci gaba da shiga iska. Hijirar cikin gida, ƙarfe a cikin ɓoyayyen yana ƙara hydrolyzed. A cikin wannan sake zagayowar, bakin karfe na austenitic yana ci gaba da lalata da sauri da sauri, kuma yana haɓaka zuwa zurfin ramin har sai an sami ɓarna.
3. Cl- yana da tasiri mai gurɓatawa a kan ɓarna. Lokacin da lalata ya fara, baƙin ƙarfe yana rasa electrons a cikin anode. Tare da ci gaba na ci gaba, baƙin ƙarfe yana ci gaba da asarar electrons, babban adadin Fe2 yana tarawa a cikin rata, kuma iskar oxygen a waje da rata ba mai sauƙin shiga ba ne. Babban wayar hannu ta Cl- ta shiga rata kuma ta samar da babban taro, FeCl2 mai jagoranci sosai tare da Fe2, kuma FeCl2 yana hydrolyzed Tsarin H yana haifar da ƙimar pH a cikin ƙwanƙwasawa zuwa 3 zuwa 4, ta haka yana ƙara lalata lalata.
Lokacin aikawa: Aug-12-2021