Umhlwa kukutshatyalaliswa okanye ukuwohloka kwemathiriyeli okanye iipropathi zazo ezibangelwa kukusingqongileyo. Uninzi lwe-corrosion lwenzeka kwindawo ye-atmospheric, equkethe amacandelo e-corrosion kunye nezinto eziphazamisayo ezifana ne-oxygen, ukufuma, utshintsho lobushushu kunye nezinto ezingcolisayo.
I-Cyclic Corrosion yinto eqhelekileyo kunye neyona nto iyonakalisayo emoyeni. I-Cyclic Corrosion corrosion phezu kwezinto zetsimbi ngenxa ye-ion ye-chloride equlethwe kwi-metal surface ye-oxidized layer kunye ne-protect layer ye-metal surface penetration kunye ne-metal electrochemical reaction yangaphakathi ebangelwa. Kwangaxeshanye, ion chlorine ziqulathe amandla athile hydration, kulula ukuba adsorbed kwi pores of the surface metal, iintanda ezixineneyo kwaye endaweni ioksijini kucwecwe oxide, iioksidi ezinganyibilikiyo zibe chlorides enyibilikayo, ukuze passivation of the state of the surface ibe yindawo esebenzayo.
Uvavanyo lweCyclic Corrosion luhlobo lovavanyo lokusingqongileyo ikakhulu kusetyenziswa izixhobo zovavanyo lweCyclic Corrosion ukwenza ukulinganisa okungeyomfuneko kweemeko zokusingqongileyo zeCyclic Corrosion ukuvavanya ukuxhathisa kokutya kweemveliso okanye izinto zentsimbi. Yahlulwe yangamacandelo amabini, enye yovavanyo lokuvezwa kokusingqongileyo kwendalo, olunye lolokulinganisa okukhawulezileyo okwenziweyo kovavanyo lokusingqongileyo lweCyclic Corrosion.
Ukulinganisa okwenziweyo kovavanyo lokusingqongileyo lweCyclic Corrosion kukusetyenziswa komthamo othile wesixhobo sovavanyo lwendawo - iCyclic Corrosion test room (Figure), kumthamo wayo wendawo ngeendlela ezenziweyo, okukhokelela kwimekobume yeCyclic Corrosion ukuvavanya umgangatho wokumelana nokugqwala kwemveliso yeCyclic Corrosion.
Ithelekiswa nokusingqongileyo kwendalo, ityuwa yekloridi yendawo engqongileyo yeCyclic Corrosion, inokuba ngamaxesha aliqela okanye izihlandlo ezininzi ngokwendalo jikelele umxholo weCyclic Corrosion, ukuze izinga lokubola linyuke kakhulu, uvavanyo lweCyclic Corrosion kwimveliso, ixesha lokufumana iziphumo nalo lifutshane kakhulu. Njengokuvezwa kwendalo kuvavanyo lwesampulu yemveliso, ukuba ngumhlwa kwayo kunokuthatha unyaka oyi-1, ngelixa ukulinganisa okwenziweyo kweemeko zokusingqongileyo zeCyclic Corrosion, okoko nje iiyure ezingama-24, ungafumana iziphumo ezifanayo.
ILabhoratri efanisiweyo yeCyclic Corrosion inokohlulwa ibe ziindidi ezine
(1)Uvavanyo lwe-Cyclic Corrosion engathathi hlangothi (uvavanyo lwe-NSS)yindlela yokuvavanya umhlwa ekhawulezileyo evele kwantlandlolo kwaye ngoku yeyona isetyenziswa kakhulu. Isebenzisa i-5% ye-sodium chloride isisombululo se-saline, isisombululo se-PH yexabiso elihlengahlengisiweyo kwibala elingathathi hlangothi (6.5 ~ 7.2) njengesisombululo sokutshiza. Ubushushu bovavanyo kuthathwa 35 ℃, izinga lokuhlaliswa kweemfuno zeCyclic Corrosion kwi-1 ~ 2ml/80cm / h.
(2)Uvavanyo lwe-Acetic acid Cyclic Corrosion (uvavanyo lwe-ASS)iphuhliswa ngesiseko sovavanyo olungathathi hlangothi lweCyclic Corrosion. Kukongeza i-acetic acid ye-glacial kwi-5% yesisombululo se-sodium chloride, ukwenzela ukuba ixabiso le-PH lesisombululo lincitshiswe malunga ne-3, isisombululo siba ne-acidic, kwaye ukubunjwa kokugqibela kwe-Cyclic Corrosion kutshintshile kwakhona kwi-Cyclic Corrosion engathathi hlangothi ukuya kwi-acidic. Izinga lomhlwa limalunga namaxesha ama-3 ngokukhawuleza kunovavanyo lwe-NSS.
(3)Ityuwa yobhedu ikhawulezise i-acetic acid Cyclic Corrosion test (uvavanyo lweCASS)luvavanyo olusanda kuphuhliswa lwangaphandle olukhawulezayo lweCyclic Corrosion, ubushushu bovavanyo lwe-50 ℃, isisombululo setyuwa esinetyuwa encinci yobhedu - i-chloride yobhedu, i-corrosion eyenziwe ngamandla. Izinga lokubola kwayo malunga namaxesha angama-8 kuvavanyo lwe-NSS.
(4)Uvavanyo lwe-Cyclic Corrosion olutshintshanayoluvavanyo olubanzi lweCyclic Corrosion, oluluvavanyo lweCyclic Corrosion olungathathi hlangothi kunye nokufuma okungaguqukiyo kunye novavanyo lobushushu. Isetyenziselwa ubukhulu becala kwiimveliso ezipheleleyo zohlobo lombhobho, ngokungena kwendawo efumileyo, ukuze iCyclic Corrosion iveliswe kuphela kumphezulu wemveliso, kodwa nangaphakathi kwimveliso. Yimveliso kwiCyclic Corrosion kunye nobushushu obufumayo kwiimeko ezimbini zokusingqongileyo ngokutshintshanayo, kwaye ekugqibeleni ivavanye iimpawu zombane kunye nezomatshini zemveliso yonke kunye okanye ngaphandle kotshintsho.
Iziphumo zovavanyo lovavanyo lweCyclic Corrosion zinikwa ngokubanzi ngokomgangatho kunendlela yobungakanani. Zine iindlela zokugweba ezikhethekileyo.
①indlela yokugweba yokukalangummandla womhlwa kunye nommandla opheleleyo womlinganiselo wepesenti ngokwendlela ethile yokwahlula ibe ngamanqanaba amaninzi, ukuya kwinqanaba elithile njengesiseko sokugweba esifanelekileyo, ifanelekile iisampulu ezisicaba zokuhlolwa.
②indlela yokugweba yokulinganisabububunzima besampulu ngaphambi nasemva kovavanyo lokuvavanya umhlwa, ukubala ubunzima bokulahlekelwa ngumhlwa ukugweba umgangatho wesampulu yokuxhathisa umhlwa, ifaneleke ngokukodwa uvavanyo lomgangatho wokuxhathisa isinyithi.
③indlela yokuqinisekisa inkangeleko ebolileyoyindlela yokuzimisela esemgangathweni, luvavanyo lweCyclic Corrosion, ukuba imveliso ivelisa isiganeko somhlwa ukumisela isampulu, imigangatho yemveliso ngokubanzi isetyenziswa kakhulu kule ndlela.
④indlela yohlalutyo lweenkcukacha-manani ze-corrosionibonelela ngoyilo lweemvavanyo zomhlwa, uhlalutyo lwedatha ye-corrosion, idatha ye-corrosion ukumisela inqanaba lokuzithemba kwendlela, esetyenziselwa ikakhulu ukuhlalutya, ukubola kwamanani, kunokuba ngokukodwa umgwebo womgangatho wemveliso ethile.
Uvavanyo lwe-Cyclic Corrosion yensimbi engenasici
Uvavanyo lwe-Cyclic Corrosion lwaqalwa ekuqaleni kwenkulungwane yamashumi amabini, lolona vavanyo lude kakhulu "lovavanyo lokubola", oluthandwa ngumsebenzisi wezinto ezikwaziyo ukumelana ne-corrosion, iye yaba luvavanyo "lomhlaba wonke". Ezona zizathu zingundoqo zezi zilandelayo: ① ukonga ixesha; ② ixabiso eliphantsi; ③ inokuvavanya iintlobo ngeentlobo zemathiriyeli; ④ iziphumo zilula kwaye zicacile, zilungele ukusonjululwa kweengxabano zorhwebo.
Enyanisweni, uvavanyo lwe-Cyclic Corrosion lwensimbi engenasici luyaziwa ngokubanzi - zingaphi iiyure ezinokuthi le nto ihlolwe i-Cyclic Corrosion? Abasebenzi abaqeqeshelwa umsebenzi kufuneka bangabi ngumntu ongaqhelekanga kulo mbuzo.
Abathengisi bezinto eziphathekayo badla ngokusetyenziswaukuthandabuzaunyango okanyephucula umgangatho wokukhazimlisa umphezulu, njl., ukuphucula ixesha lokuvavanya i-Cyclic Corrosion yensimbi engenasici. Nangona kunjalo, eyona nto ibalulekileyo yokumisela eyona nto kukubunjwa kwensimbi engenasici ngokwayo, oko kukuthi umxholo we-chromium, i-molybdenum kunye ne-nickel.
Okukhona uphezulu umxholo weziqalelo ezimbini, ichromium kunye nemolybdenum, kokukhona ukuqina kokusebenza komhlwa okufunekayo ukumelana nemingxuma kunye nomhlwa oqala ukubonakala. Oku kuxhathisa i-corrosion kubonakaliswe ngokubhekiselele kwinto ebizwaPitting Resistance Equivalent(PRE) ixabiso: PRE = %Cr + 3.3 x %Mo.
Nangona i-nickel ayinyusi ukuxhathisa kwentsimbi kwi-pitting kunye ne-crevice corrosion, inokucothisa ngokufanelekileyo izinga lokubola emva kokuba inkqubo yokubola iqalile. Iintsimbi ze-nickel eziqulathe i-austenitic stainless ke ngoko zikholisa ukwenza ngcono kakhulu kwiimvavanyo ze-Cyclic Corrosion, kwaye zonakaliswe kakhulu kunezintsimbi ezingenazintsimbi ze-nickel eziphantsi ze-nickel ezinokuxhathisa okufanayo ekugaleleni i-corrosion elinganayo.
I-Trivia: Kumgangatho wama-304, iCyclic Corrosion engathathi hlangothi iphakathi kweeyure ezingama-48 kunye ne-72; kumgangatho wama-316, iCyclic Corrosion engathathi hlangothi idla ngokuba phakathi kweeyure ezingama-72 nezili-120.
Kufuneka kuqatshelwe ukubaiCyclic Corrosionuvavanyo lunezithintelo ezinkulu xa uvavanya iipropati zensimbi engenasici.Umxholo we-chloride we-Cyclic Corrosion kwi-Cyclic Corrosion test iphezulu kakhulu, idlula kakhulu indawo yokwenyani, ngoko ke isinyithi esingenasici esikwazi ukuxhathisa i-corrosion kwindawo yesicelo sangempela kunye nomxholo we-chloride ophantsi kakhulu uya kuthotywa kwakhona kwi-Cyclic Corrosion test.
Uvavanyo lwe-Cyclic Corrosion luyayitshintsha indlela yokwenza umhlwa yentsimbi engatyiwayo, ayinakuthathwa njengovavanyo olukhawulezileyo okanye uvavanyo lokulinganisa. Iziphumo zicalanye kwaye azikho ubudlelwane obulinganayo kunye nokusebenza kwangempela kwensimbi engenasici ekugqibeleni isetyenziswe.
Ngoko sinokusebenzisa uvavanyo lwe-Cyclic Corrosion ukuthelekisa ukuxhathisa kwe-corrosion yeentlobo ezahlukeneyo zensimbi engenasici, kodwa olu vavanyo lukwazi ukulinganisa izinto eziphathekayo kuphela. Xa ukhetha izinto zensimbi ezingenasici ngokukodwa, uvavanyo lwe-Cyclic Corrosion lulodwa aluqhelekanga ukubonelela ngolwazi olwaneleyo, kuba asinalo ukuqonda okwaneleyo kwekhonkco phakathi kweemeko zokuvavanya kunye neyona ndawo yesicelo.
Ngesizathu esifanayo, akunakwenzeka ukuqikelela ubomi benkonzo yemveliso esekelwe kuphela kwi-Cyclic Corrosion test yesampula yensimbi engenasici.
Ukongezelela, akunakwenzeka ukwenza uthelekiso phakathi kweentlobo ezahlukeneyo zetsimbi, umzekelo, asikwazi ukuthelekisa insimbi engenasici kunye ne-carbon steel coated, kuba iindlela zokubola kwezinto ezimbini ezisetyenzisiweyo kuvavanyo zihluke kakhulu, kwaye ukulungelelaniswa phakathi kweziphumo zovavanyo kunye nemeko yangempela apho imveliso iya kugqiba ukusetyenziswa ayifani.
Ixesha lokuposa: Nov-06-2023