Lalacewa ita ce lalacewa ko tabarbarewar kayan ko kaddarorinsu sakamakon aikin muhalli.Yawancin lalacewa yana faruwa a cikin yanayi na yanayi, wanda ya ƙunshi abubuwa masu lalata da abubuwa masu lalata kamar oxygen, zafi, canjin yanayi da kuma gurɓatawa.
Lalacewar feshin gishiri abu ne na gama-gari kuma mafi ɓarna nau'in lalatawar yanayi.Lalacewar fesa gishiri a saman kayan ƙarfe yana faruwa ne ta hanyar ions chloride da ke ƙunshe a saman ƙarfen da ke shiga ta cikin Layer oxidation da Layer na kariya da na ciki na ƙarfe na lantarki.A lokaci guda, ion chloride yana ƙunshe da wani adadin kuzari na hydration, wanda ke da sauƙi a sanya shi a cikin pores na karfe da fashe da kuma maye gurbin iskar oxygen a cikin Layer oxide, don haka ya canza oxide mai narkewa zuwa chloride mai narkewa da passivated. yanayin yanayi a cikin wani wuri mai aiki.
Gishirilalata kariya fesaGwajin gwaji ne na muhalli wanda galibi yana amfani da yanayin yanayin feshin gishiri na wucin gadi wanda kayan aikin gwajin gishiri suka ƙirƙira don tantance juriyar lalata samfuran ko kayan ƙarfe.Ya kasu zuwa nau'ikan gwaje-gwaje guda biyu: gwajin bayyanar yanayin yanayi, da ingantaccen simintin simintin gyaran muhalli na fesa gishiri.
A cikin gwajin yanayi na feshin gishiri na wucin gadi, ana amfani da ɗakin gwajin gishiri mai ɗan ƙaramin sarari, kuma ana samar da yanayin feshin gishiri ta hanyar amfani da hanyoyin wucin gadi a cikin girman sararin samaniya, don tantance aiki da ingancin lalatawar gishiri. juriya na samfurori.
Matsakaicin gishiri na chloride a cikin yanayin fesa gishiri na iya zama sau da yawa ko sau da yawa abin da ke cikin gishirin fesa a cikin yanayi na yau da kullun, don haka yana haɓaka ƙimar lalata kuma yana rage lokacin samun sakamako.Misali, yana iya ɗaukar shekara ɗaya don lalata lokacin gwada samfurin samfur a cikin yanayin bayyanar halitta, yayin da zaku iya samun irin wannan sakamakon gwajin bayan sa'o'i 24 a cikin yanayin fesa gishirin simintin wucin gadi.
Za a iya raba feshin gishirin da aka kwaikwayi na dakin gwaje-gwaje zuwa kashi hudu.
(1) Gwajin feshin gishiri mai tsaka-tsaki (gwajin NSS) ita ce hanya mafi sauri kuma mafi yawan amfani da hanyar gwajin lalata.Yana amfani da 5% sodium chloride bayani na ruwan gishiri, tare da ƙimar pH da aka daidaita zuwa kewayon tsaka tsaki (6.5 ~ 7.2) azaman maganin fesa.Gwajin zafin jiki shine 35 ℃, kuma ƙimar da ake buƙata na lalata gishiri shine 1 ~ 2ml / 80cm / h.
(2) Gwajin gwajin gishiri na acetic acid (gwajin ASS) an haɓaka shi akan gwajin feshin gishiri mai tsaka tsaki.Yana cikin 5% sodium chloride bayani tare da wasu glacial acetic acid, don haka da cewa bayani PH darajar an rage zuwa game da 3, da bayani zama acidic, da gishiri fesa kafa a karshe ya zama acidic daga tsaka tsaki gishiri fesa.Adadin lalatarsa ya kusan sau 3 sauri fiye da gwajin NSS.
(3) Gwajin saurin feshin gishirin jan karfe (gwajin CASS) sabon gwajin lalata gishirin gishiri ne na waje.Gwajin zafin jiki shine 50 ℃.Ana ƙara ƙaramin adadin gishiri-jan karfe chloride a cikin maganin gishiri don haifar da lalata sosai.Adadin lalatarsa kusan sau 8 ne na gwajin NSS.
(4) Madadin gwajin feshin gishiri shine cikakken gwajin feshin gishiri, wanda a zahiri gwajin feshin gishiri ne mai tsaka tsaki tare da yawan zafi da gwajin zafi.Ana amfani da shi musamman don samfurin nau'in rami.Ta hanyar shiga cikin yanayin tudun ruwa, ana samar da lalatawar gishiri ba kawai a saman ba har ma a cikin samfurin.Ana canza samfurin a madadin ruwan gishiri da zafi da yanayin zafi, sa'an nan kuma ya kamata a tantance kayan lantarki da injiniyoyi na samfurin don kowane canji.
Ƙaddamar da sakamako
Sakamakon gwaji na gwajin feshin gishiri ana ba da shi gabaɗaya a sigar inganci maimakon ƙididdiga.Akwai takamaiman hanyoyi guda huɗu na ƙaddara.
(1) Hanyar tantance ƙima.
A cikin wannan hanyar, raba rabon yanki na lalata da jimillar yanki zuwa matakai da yawa, kuma ƙayyade wani matakin a matsayin ingantaccen tushe don ƙaddara.Wannan hanya ta dace don kimanta samfuran lebur.
(2) Hanyar tantance ma'auni.
Ta hanyar auna nauyin samfurin kafin da kuma bayan gwajin lalata, ƙididdige nauyin da aka rasa saboda lalata, kuma kuyi hukunci dafesa kariya lalataingancin samfurin.Wannan hanya ta dace musamman don kimanta ƙimar juriya na lalata ƙarfe.
(3) Hanyar binciken ƙididdiga bayanan lalata.
Wannan hanyar tana ba da matakin amincewa na ƙirar gwaje-gwajen lalata, nazarin bayanan lalata, da tantance bayanan lalata, waɗanda galibi ana amfani da su don bincike da ƙididdiga na lalata, maimakon musamman don ƙayyadaddun ingancin samfur.
Gwajin fesa gishiri na bakin karfe
Tun da aka ƙirƙira a farkon karni na ashirin, gwajin feshin gishiri ya sami tagomashi sosai daga masu amfani da kayan da ke jure lalata saboda fa'idodinsa da suka haɗa da rage lokaci da farashi, mai iya gwada abubuwa iri-iri, da samar da sakamako mai sauƙi da haske.
A aikace, gwajin feshin gishiri na bakin karfe shine wanda aka fi sani da shi, kuma dole ne masu aikin su san tsawon sa'o'i na gwajin gishirin zai iya wuce wannan kayan.
Dillalan kayan aiki galibi za su tsawaita lokacin gwajin bakin karfe na fesa gishiri tare da hanyoyi kamar wucewa ko ƙara darajar goge saman.Koyaya, mafi mahimmancin ƙayyadaddun abu shine abun da ke cikin bakin karfe da kansa, watau abun ciki na chromium, molybdenum da nickel.
Mafi girman abun ciki na chromium da molybdenum, mafi girman juriyar lalata da ake buƙata don ramuwa da lalata don fara bayyana.Ana bayyana wannan juriyar lalata ta abin da ake kira daidai da juriya na pitting (PRE): PRE =% Cr + 3.3 x% Mo.
Duk da yake nickel baya ƙara juriyar ƙarfe zuwa rami da lalata lalata, yana iya yin tasiri a rage saurin lalata da zarar tsarin lalata ya fara.Don haka, bakin karfe na austenitic mai dauke da nickel yakan yi kyau sosai a gwajin feshin gishiri da tsatsa da yawa kasa da karamin karfen nickel feritic bakin karfe masu kama da juriya iri daya.
Ya kamata a lura cewa gishirilalata kariya fesagwajin yana da manyan kurakurai lokacin gwada aikin bakin karfe.Abubuwan da ke cikin sinadarin chloride na feshin gishiri a gwajin feshin gishiri yana da girma sosai kuma ya zarce yanayin da ake ciki, don haka bakin karfen da zai iya tsayayya da lalata a ainihin aikace-aikacen da ke da karancin sinadarin chloride shima zai lalace a gwajin feshin gishiri.
Gwajin feshin gishiri yana canza halayen lalata na bakin karfe, wanda ba za'a iya la'akari da shi ba gwajin gaggawa ba ko gwajin siminti.Sakamakon yana da gefe ɗaya kuma ba su da dangantaka mai kama da ainihin aikin bakin karfe wanda aka yi amfani da shi a ƙarshe.
Don haka zaku iya amfani da gwajin feshin gishiri don kwatanta juriya na lalata nau'ikan bakin karfe daban-daban, amma wannan gwajin yana da ikon tantance kayan kawai.Lokacin zabar takamaiman kayan bakin karfe, gwajin feshin gishiri kadai yawanci baya samar da isassun bayanai saboda alakar da ke tsakanin yanayin gwajin da ainihin yanayin aikace-aikacen ba kasafai ake sani ba.
Bugu da kari, ba za a iya kwatanta nau'ikan karfe daban-daban da juna ba, saboda kayan biyu da aka yi amfani da su a cikin gwajin suna da nau'ikan lalata daban-daban, don haka sakamakon gwajin da kuma dacewa da ainihin amfani da muhalli ba iri ɗaya bane.
Lokacin aikawa: Jul-08-2022