Ndiyabulela ngokundwendwela i-Nature.com.Uguqulelo lwesikhangeli oyisebenzisayo lunenkxaso elinganiselweyo ye-CSS.Ukufumana amava angcono kakhulu, sincoma ukuba usebenzise i-browser ehlaziyiweyo (okanye ucime imodi yokuhambelana kwi-Internet Explorer). Okwangoku, ukuqinisekisa inkxaso eqhubekayo, siya kubonisa isayithi ngaphandle kwezitayela kunye neJavaScript.
Intsimbi ye-20MnTiB yeyona nto isetyenziswa kakhulu kwibholithi ephezulu yokuqina kwebhulorho kwilizwe lam, kwaye ukusebenza kwayo kubaluleke kakhulu ekusebenzeni okukhuselekileyo kweebhulorho. Ngokusekwe kuphando lwemekobume yomoya eChongqing, olu phononongo lwenze isisombululo somhlwa esilinganisa imozulu efumileyo yeChongqing, kwaye yaqhuba uvavanyo loxinzelelo lwemozulu epholileyo. I-Chongqing.Iimpembelelo zeqondo lobushushu, ixabiso le-pH kunye nokuxinana kwesisombululo se-corrosion efanisiweyo kukuziphatha koxinzelelo lwe-corrosion ye-20MnTiB ye-bolts high-power bolts yafundwa.
I-20MnTiB yensimbi iyona nto isetyenziswa kakhulu i-bolt high-sight-bolt material for steel structure bridges kwilizwe lam, kwaye ukusebenza kwayo kubaluleke kakhulu ekusebenzeni okukhuselekileyo kweebhulorho.Li et al. I-1 ivavanye iipropathi zentsimbi ye-20MnTiB eqhele ukusetyenziswa kwibakala le-10.9 iibholiti zokuqina okuphezulu kwinqanaba lobushushu obuphezulu be-20 ~ 700 ℃, kwaye yafumana i-curve yoxinzelelo-strain, amandla esivuno, amandla okuqina, imodyuli yoMncinci, kunye nobude. kunye ne-coefficient yokwandisa.Zhang et al. 2, Hu et al. I-3, njl., ngovavanyo lokubunjwa kweekhemikhali, uvavanyo lwepropathi yomatshini, uvavanyo lwe-microstructure, uhlalutyo lwe-macroscopic kunye ne-microscopic ye-thread surface, kunye neziphumo zibonisa ukuba esona sizathu sibalulekileyo sokuqhekeka kweebholiti zamandla aphezulu zihambelana neziphene zentambo, kunye nokuvela kweziphene zentambo Ukugxininiswa okukhulu koxinzelelo, ukugxininiswa kwe-crack tip kunye ne-open-air corrosion corrosion.
Iibholiti eziphezulu zentsimbi yeebhulorho zentsimbi zidla ngokusetyenziswa ixesha elide kwindawo efumileyo.Izinto ezifana nokufuma okuphezulu, ubushushu obuphezulu, kunye nentlenga kunye nokufunxwa kwezinto eziyingozi kwimo engqongileyo kunokubangela ukuba kube lula ukubola kwezakhiwo zentsimbi.I-Corrosion inokubangela ilahleko ephezulu yamandla ebholiti, okukhokelela ekuqhekekeni kunye neentanda ezininzi. ukunciphisa ubomi be-bolts-high-high and even cause them to break.Okwangoku, kukho izifundo ezininzi malunga nomphumo wokusingqongileyo kwi-corrosion ye-corrosion yokusebenza kwengcinezelo yezinto eziphathekayo.I-Catar et al4 iphande ngokuziphatha kwe-corrosion yoxinzelelo lwe-magnesium alloys kunye nemixholo eyahlukeneyo ye-aluminium kwi-acidic, i-alkaline kunye ne-neutral environments ngokucotha kwe-straining vavanyo lwe-altrocorsion kunye nokuhlolwa kwe-electrot ye-strain5. ukuziphatha kwe-Cu10Ni i-alloy kwi-3.5% isisombululo se-NaCl phambi koxinzelelo oluhlukeneyo lwee-ion ze-sulfide. U-Aghion et al.6 uvavanye ukusebenza kwe-corrosion ye-die-cast magnesium alloy MRI230D kwi-3.5% isisombululo se-NaCl ngovavanyo lokucwiliswa, uvavanyo lokutshiza ityuwa, uhlalutyo lwe-potentiodynamic alrocort yokuziphatha kunye nokuhlaziywa kokuziphatha kwe-polarization ye-stress. I-9Cr martensitic steel isebenzisa i-SSRT kunye nobuchule bemveli bokuvavanya i-electrochemical, kwaye ifumene umphumo we-chloride ion kwi-static corrosion behavior ye-martensitic steel kwiqondo lokushisa eliqhelekileyo.U-Chen et al.8 uphande ngokuziphatha kwe-corrosion ye-stress kunye ne-cracking ye-X70 yensimbi kwisisombululo sodaka lolwandle olufanisiweyo oluqulethe i-SRB kumaqondo ahlukeneyo obushushu obusetyenziswa yi-SSRTT kunye nefuthe lobushushu obusetyenzisiweyo yi-SSRTT.9 izinga loxinzelelo kuxinzelelo lwe-corrosion resistance kumanzi olwandle lwe-00Cr21Ni14Mn5Mo2N austenitic stainless steel stainless.Iziphumo zibonisa ukuba ubushushu kuluhlu lwe-35 ~ 65℃ alunampembelelo ebalulekileyo ekuziphatheni koxinzelelo lwe-corrosion yensimbi engenasici.Lu et al. I-10 ivavanye ukulibaziseka kwe-fracture susceptibility of samples with different tensile power grades by a dead loaded delayed fracture test and SSRT.Kucetyiswa ukuba ukuqina kokuqina kwe-20MnTiB yentsimbi kunye ne-35VB ye-bolts yentsimbi ephezulu kufuneka ilawulwe kwi-1040-1190MPa ye-MPa.Nangona kunjalo, ininzi ye-5 yesisombululo esisisiseko kwi-5% yesisombululo esilula. indawo engcolisayo, ngelixa indawo eyiyo yokusetyenziswa kweebholiti eziphezulu zokuqina zinzima kakhulu kwaye zinezinto ezininzi ezichaphazelayo, ezifana nexabiso le-pH ye-bolt.Ananya et al. I-11 ifunde umphumo weeparameters zokusingqongileyo kunye nezinto eziphathekayo kwindawo ephazamisayo kwi-corrosion kunye noxinzelelo lwe-corrosion cracking ye-duplex stainless steels.Sunada et al. I-12 iqhube iimvavanyo zokuqhekeka kweqondo lokushisa kwegumbi kwi-SUS304 intsimbi kwizisombululo ezinamanzi eziqulathe i-H2SO4 (0-5.5 kmol/m-3) kunye ne-NaCl (0-4.5 kmol/m-3) Uxinzelelo lwe-CO2 / CO, uxinzelelo lwegesi kunye nexesha lokubola kuxinzelelo lwe-corrosion susceptibility ye-A516 isitya soxinzelelo lwentsimbi. Ukusebenzisa isisombululo se-NS4 njengesisombululo sokulinganisa amanzi aphantsi komhlaba, u-Ibrahim et al. I-14 iphande isiphumo seeparamitha zokusingqongileyo ezifana ne-bicarbonate ion (HCO) yoxinaniso, i-pH kunye nobushushu kwi-stress corrosion cracking ye-API-X100 yentsimbi yombhobho emva kokuxobula i-coating.Shan et al. I-15 yafunda umthetho wokutshintsha koxinzelelo lwe-corrosion cracking susceptibility of austenitic stainless steel 00Cr18Ni10 kunye nobushushu phantsi kweemeko ezahlukeneyo zobushushu (30 ~ 250 ℃) phantsi kwemeko yamanzi amnyama aphakathi kwisityalo esifanisiweyo samalahle ukuya kwi-hydrogen nge-SSRT. Ukulibaziseka kovavanyo lwe-fracture kunye ne-SSRT.Zhao17 ifunde iziphumo ze-pH, i-SO42-, i-Cl-1 kwindlela yokuziphatha yoxinzelelo lwe-GH4080A i-alloy nge-SSRT.Iziphumo zibonisa ukuba ixabiso eliphantsi le-pH, ukunyanzeliswa koxinzelelo lwe-corrosion ye-GH4080A i-alloy.Inoxinzelelo olucacileyo kwi-corrosion ye-2 kunye ne-isonic corrosion. ubushushu begumbi.Nangona kunjalo, kukho izifundo ezimbalwa malunga nomphumo we-corrosion yendalo kwi-20MnTiB yentsimbi ye-bolts high-power bolts.
Ukuze ufumane izizathu zokungaphumeleli kweebholiti eziphezulu ezisetyenziswa kwiibhulorho, umbhali uye wenza uthotho lwezifundo.Iisampulu zebholithi zamandla aphezulu zakhethwa, kwaye izizathu zokungaphumeleli kwezi sampuli zaxoxwa ngemibono yokwakheka kweekhemikhali, i-fracture microscopic morphology, i-metallographic structure kunye ne-mechanical properties analysis19, i-20 phendong yophando kwiminyaka yakutshanje kwi-congqing yophando kwiminyaka yakutshanje. Kuyilwe isikimu somhlwa esilinganisa imozulu efumileyo yaseChongqing. Imifuniselo yoxinzelelo lwe-corrosion, imifuniselo ye-electrochemical corrosion kunye ne-corrosion fatigue experiments zeebholiti zamandla aphezulu e-Chongqing ezifanisiweyo zemozulu efumileyo zenziwe.Kolu phononongo, iziphumo zobushushu, ixabiso le-pH kunye nokuxinana kwesisombululo esifanisiweyo sokutya kwi-corrosion ye-20M ye-corrosion ye-20M yotyalo-mali. ngovavanyo lwepropathi yoomatshini, uhlalutyo olukhulu lwe-fracture kunye ne-microscopic, kunye neemveliso zokubola komphezulu.
IChongqing ikumzantsi-ntshona weChina, iindawo eziphezulu zoMlambo iYangtze, kwaye inemozulu efumileyo yemonsoon.Iqondo lobushushu lonyaka yi-16-18°C, umyinge wonyaka wokufuma kwesalamane ubukhulu becala yi-70-80%, iiyure zonyaka zokukhanya kwelanga ziiyure eziyi-1000-1400, kunye nepesenteji yelanga-35 kuphela.
Ngokweengxelo ezinxulumene nokukhanya kwelanga kunye nobushushu be-ambient e-Chongqing ukusuka ngo-2015 ukuya ku-2018, i-avareji yobushushu bemihla ngemihla e-Chongqing isezantsi nge-17°C kwaye iphezulu ukuya kuma-23°C. Elona qondo lobushushu liphezulu kumzimba webhulorho ye-Chaotianmen Bridge e-Chongqing linokufikelela kwi-50 ° C °C21,22. Ngoko ke, amanqanaba obushushu ovavanyo lwe-corrosion yoxinzelelo abekwe kwi-25 ° C kunye ne-50 ° C.
Ixabiso le-pH yesisombululo esilinganisiweyo somhlwa simisela ngokuthe ngqo ubungakanani be-H +, kodwa oko akuthethi ukuba ixabiso le-pH liphantsi, ukuhlwa kulula kwenzeka.Impembelelo ye-pH kwiziphumo iya kuhluka kwizinto ezahlukeneyo kunye nezisombululo. Ukuze ufunde kakuhle umphumo wesisombululo esilinganisiweyo somhlwa kwintsebenzo yoxinzelelo lwe-corrosion ye-high-high-stresion, i-pH ye-5 corrosion. kunye ne-7.5 ngokudibanisa nophando loncwadi23 kunye noluhlu lwe-pH yamanzi emvula yonyaka e-Chongqing.2010 ukuya ku-2018.
Ukuphakama koxinzelelo lwesisombululo se-corrosion esifanisiweyo, umxholo we-ion kwisisombululo esifanisiweyo sokuhlwa, kunye nempembelelo enkulu kwizinto eziphathekayo. Ukuze ufunde impembelelo yesisombululo se-corrosion esilinganisiweyo kwi-corrosion yoxinzelelo lwe-bolts, i-laboratory eyenziwe yakhawulezisa uvavanyo lwe-corrosion luye lwamiselwa, kunye ne-concentration ye-corrosion ye-corrosion yamiselwa, kunye ne-concentration ye-corrosion level. i-original simulated corrosion solution concentration (1 ×), i-20 × i-original simulated corrosion solution concentration (20 ×) kunye ne-200 × i-original simulated corrosion solution concentration (200 ×).
Imo engqongileyo enobushushu be-25℃, ixabiso le-pH le-5.5, kunye nokuxinwa kwesisombululo se-corrosion yasekuqaleni yeyona nto isondeleyo kwiimeko ezichanekileyo zokusetyenziswa kweebholiti eziphezulu zamandla eebhulorho.Nangona kunjalo, ukuze kukhawuleziswe inkqubo yovavanyo lwe-corrosion, iimeko zovavanyo kunye nobushushu be-25 °C, i-pH ye-5.20 × i-corrosion ye-concentration yayiyi-reference ye-5.5 × i-corrosion ye-original kunye ne-corrosion. iqela lokulawula.Xa iimpembelelo zeqondo lokushisa, ukugxininiswa okanye ixabiso le-pH yesisombululo esifanisiweyo sokugqwala kwintsebenzo yoxinzelelo lwe-corrosion ye-bolts high-power bolts iphandwa ngokulandelanayo, ezinye izinto zahlala zingatshintshi, ezisetyenziswe njengenqanaba lokulinga leqela lokulawula ireferensi.
Ngokwe-2010-2018 inkcazo yomgangatho wokusingqongileyo womoya ekhutshwe yi-Chongqing Municipal Bureau of Ecology and Environment, kwaye ibhekiselele kumacandelo emvula exelwe kwiZhang24 kunye nolunye uncwadi oluxelwe eChongqing, isisombululo somhlwa esisekwe ekonyuseni koxinzelelo lwe-SO42- sayilwa. isisombululo somhlwa esifanisiweyo siboniswe kwiTheyibhile 1:
Isisombululo se-corrosion esilinganisiweyo silungiswa nge-chemical ion concentration balance method usebenzisa i-reagents analytical kunye ne-distilled water.Ixabiso le-pH yesisombululo esilinganisiweyo somhlwa salungiswa nge-pH meter echanekileyo, isisombululo se-nitric acid kunye nesisombululo se-sodium hydroxide.
Ukuze ukulinganisa imozulu efumileyo eChongqing, umhloli wetyuwa wetyuwa uguqulwe ngokukodwa kwaye uyilwe 25. Njengoko kubonisiwe kuMzobo 1, izixhobo zokulinga zineenkqubo ezimbini: inkqubo yokutshiza ityuwa kunye nenkqubo yokukhanyisa. Inkqubo yokutshiza ityuwa ngumsebenzi oyintloko wezixhobo zokulinga, ezibandakanya inxalenye yokulawula, inxalenye yokutshiza kunye nenxalenye ye-induction. inxalenye iqulethwe ngezinto zokulinganisa ubushushu, ezibonisa ubushushu kwigumbi lovavanyo.Inxalenye yolawulo yenziwe yi-microcomputer, edibanisa inxalenye yokutshiza kunye nenxalenye yokungeniswa ukulawula yonke inkqubo yovavanyo.Inkqubo yokukhanyisa ifakwe kwigumbi lokuvavanya ityuwa yokutshiza ukulinganisa ukukhanya kwelanga.Inkqubo yokukhanyisa iqulethe izibane ze-infrared kunye nesilawuli sexesha.Ngexesha elifanayo lokuvavanya kwi-sensor yokushisa, i-monitor yesampulu efakwe kwi-test sensor kwi-test efakwe kwi-test sensor. Ixesha elilungile.
Iisampulu ze-Stress corrosion phantsi komthwalo oqhubekayo zicutshungulwe ngokuhambelana ne-NACE TM0177-2005 (Uvavanyo lweLabhoratri ye-Sulfide Stress Cracking kunye ne-Stress Corrosion Cracking Resistance of Metals in an H2S Environmental) Imizekelo ye-corrosion ye-Stress yahlanjululwa kuqala nge-acetone kunye ne-ultrasonic mechanical cleaned kunye ne-ultrasonic mechanical cleaning kunye ne-oil denhydrated yokucoca kunye ne-oil denhydrated yokucoca kunye ne-oil denhydrated yokucoca kunye ne-oil denhydrate. iisampulu ezicocekileyo kwigumbi lovavanyo lwesixhobo sovavanyo lokutshiza ityuwa ukulinganisa imeko yomhlwa kwindawo efumileyo yemozulu yeChongqing.Ngokutsho komgangatho we-NACE TM0177-2005 kunye nomgangatho wovavanyo lwetyuwa yokutshiza i-GB/T 10,125-2012, ixesha lovavanyo loxinzelelo lwe-corrosion rhoqo kolu phononongo luqhutywa ngokulinganayo kwi-test68 testhrosion. phantsi kweemeko zomhlwa ezahlukeneyo kwi-MTS-810 umatshini wokuvavanya ukuqina kwehlabathi, kunye neempawu zabo zoomatshini kunye ne-morphology ye-fracture corrosion yahlalutywa.
Umzobo we-1 ubonisa i-macro- kunye ne-micro-morphology ye-surface corrosion ye-high-strength-bolt stress stress corrosion specimens phantsi kweemeko ezahlukeneyo zokubola.2 kunye ne-3 ngokulandelanayo.
I-Macroscopic morphology ye-stress corrosion specimens ze-20MnTiB iibholiti zamandla aphezulu phantsi kweemeko-bume zomhlwa ezifanisiweyo ezahlukeneyo: (a) akukho mhlwa; (b) ixesha eli-1; (c) 20 ×; (d) 200 ×; (e) pH3.5; (f) pH 7.5; (g) 50°C.
I-Micromorphology yeemveliso ze-corrosion ye-20MnTiB i-bolts yamandla aphezulu kwiindawo ezahlukeneyo zokubola okufanisiweyo (100 ×): (a) ixesha le-1; (b) 20 ×; (c) 200 ×; (d) pH3.5; (e) pH7 .5; (f) 50°C.
Inokubonwa ukusuka Fig. 2a ukuba umphezulu uncorroded high-amandla bolt umfuziselo ubonisa ukukhazimla metallic eqaqambileyo ngaphandle corrosion.Noko ke, phantsi kwemeko yesisombululo yoqobo eyenziwe umhlwa (Fig. 2b), umphezulu isampulu yayigutyungelwe ngokuyinxenye kunye ne-tan kunye nomdaka-red-bomvu umhlwa iimveliso, kwaye ezinye iindawo ezicacileyo zemveliso yentsimbi kuphela, kwaye ezinye iindawo ezicacileyo zomphezulu wentsimbi, kwaye ezinye iindawo ezicacileyo zomphezulu wensimbi i-corrode kancinane, kunye nesisombululo somhlwa esifanisiweyo asizange sibe nempembelelo kumphezulu wesampuli. Iimpawu zezinto eziphathekayo zinempembelelo encinci.Nangona kunjalo, phantsi kwemeko ye-20 × yoqobo yoxinaniso lwesisombululo somhlwa (umzobo 2c), umphezulu wesampulu yebholithi ephezulu yokuqina igutyungelwe ngokupheleleyo sisixa esikhulu semveliso ye-tan corrosion kunye nesixa esincinci se-brown-red corrosion.product, akukho luster ecacileyo yesinyithi yafunyanwa, kwaye kukho imveliso emdaka kufutshane nomphezulu we-brown-blate. phantsi kwemeko ye-200 × yoqobo yoxinaniso lwesisombululo somhlwa esifanisiweyo (Umfanekiso 2d), umphezulu wesampulu ugutyungelwe ngokupheleleyo yimveliso ye-corrosion emdaka, kunye neemveliso zomhlwa ezimdaka zibonakala kwezinye iindawo.
Njengoko i-pH yehla ukuya kwi-3.5 (umzobo 2e), iimveliso ze-corrosion ezinemibala ye-tan yayiyeyona nto iphezulu phezu kweesampuli, kwaye ezinye zeemveliso ze-corrosion ziye zakhutshwa.
Umfanekiso we-2g ubonisa ukuba njengoko ubushushu bukhula ukuya kuma-50 ° C, umxholo weemveliso ezimdaka-ebomvu kumphezulu wesampuli uyancipha ngokukhawuleza, ngelixa iimveliso ze-corrosion ezikhanyayo zigubungela umphezulu wesampuli kwindawo enkulu.Imveliso yemveliso ye-corrosion ikhululekile, kwaye ezinye iimveliso ezimdaka-ezimnyama zixotshiwe.
Njengoko kubonisiwe kwi-Figure 3, phantsi kweemeko ezahlukeneyo ze-corrosion, iimveliso ze-corrosion kumphezulu we-20MnTiB i-bolt high-strength bolt stress corrosion specimens ngokucacileyo zihlanjululwe, kwaye ubukhulu be-corrosion layer inyuka ngokunyuka koxinzelelo lwesisombululo se-corrosion esifanisiweyo. isampuli inokwahlulwa ibe ngamacandelo amabini: uluhlu lwangaphandle lweemveliso ze-corrosion lusasazwa ngokulinganayo, kodwa inani elikhulu lokuqhekeka livela; umaleko wangaphakathi yiqela elikhululekileyo lemveliso ye-corrosion.Ngaphantsi kwemeko ye-20 × ye-concentration ye-corrosion ye-original efaniswayo (Umfanekiso we-3b), i-corrosion layer phezu kwesampulu inokwahlulwa ibe ngamaleko amathathu: umaleko ongaphandle uhlakazekile imveliso ye-corrosion ye-cluster, ekhululekile kunye ne-porous, kwaye ayinayo intsebenzo enhle; Uluhlu oluphakathi luluhlu lwemveliso ye-corrosion efanayo, kodwa kukho ukuqhekeka okucacileyo, kwaye i-ion ye-corrosion ingadlula kwiindawo eziqhekezayo kwaye ichithe i-substrate; umaleko wangaphakathi ngumaleko oshinyeneyo wemveliso ngaphandle kokuqhekeka okucacileyo, onesiphumo esihle sokukhusela kwi-substrate.Phantsi kwemeko ye-200 × yoqobo yoxinaniso lwesisombululo somhlwa (umzobo 3c), umaleko wokutya kumphezulu wesampulu unokwahlulwa ube ngamacandelo amathathu: umaleko ongaphandle ngumaleko obhityileyo kunye nofanayo; umaleko ophakathi ubukhulu becala i-petal-shaped and flake-shaped corrosion Umaleko wangaphakathi ngumaleko oshinyeneyo wemveliso ngaphandle kokuqhekeka okucacileyo kunye nemingxuma, enefuthe elihle lokukhusela kwi-substrate.
Ingabonwa kwi-Fig. 3d ukuba kwindawo efaniswayo ye-corrosion ye-pH 3.5, kukho inani elikhulu leemveliso ze-flocculent okanye iinaliti ezifana neenaliti kumphezulu we-20MnTiB i-bolt high-strength specimen. i-corrosion layer ineentanda ezicacileyo.
Inokubonwa kumfanekiso we-3f ukuba xa ubushushu bonyuka ukuya kuma-50 °C, akukho maleko exineneyo yangaphakathi efunyenweyo kwisakhiwo somaleko we-corrosion, ebonisa ukuba kukho izikhewu phakathi kwamaleko e-corrosion kwi-50 °C, nto leyo eyenza ukuba i-substrate ingagqunywanga ngokupheleleyo yimveliso ye-corrosion. Ibonelela ngokhuseleko ekwandeni kokutya komhlwa kwi-substrate.
Iipropathi zoomatshini zeebholithi zokuqina okuphezulu phantsi koxinzelelo loxinzelelo loxinzelelo oluqhubekayo kwiindawo ezahlukeneyo ezinomhlwa zibonisiwe kwiTheyibhile 2:
Inokubonwa kwiThebhile 2 ukuba iipropathi zoomatshini ze-20MnTiB zesampulu zebholithi yokuqina okuphezulu zisahlangabezana neemfuno ezisemgangathweni emva komjikelo owomileyo omanzi okhawulezileyo wovavanyo lokuthotywa kwiindawo ezahlukeneyo zomhlwa ezifanisiweyo, kodwa kukho umonakalo othile xa kuthelekiswa nezingagxwangayo.Isampuli. I-20 × okanye i-200 × i-concentration yesisombululo esilinganisiweyo, ukunyuswa kwesampulu yehla kakhulu.Iimpawu zomatshini zifana nokugxininiswa kwe-20 × kunye ne-200 × izisombululo ze-corrosion zangaphambili ezifanisiweyo.Xa ixabiso le-pH lesisombululo esilinganisiweyo se-corrosion sehla kwi-3.5, amandla okuqina kunye nokuphakama kwe-elongation ye-5 ° yehla kakhulu, i-elongation ye-elongation ye-5 ° iyancipha kakhulu kwaye i-elongation ye-elongation ye-C. kuncipha kakhulu, kwaye izinga lokuncipha kwendawo lisondele kakhulu kwixabiso eliqhelekileyo.
I-morphology ye-fracture ye-20MnTiB i-bolt high-strength-bolt stress corrosion specimens phantsi kweendawo ezahlukeneyo zokubola ziboniswa kwi-Figure 4, eyi-macro-morphology ye-fracture, i-fiber zone embindini we-fracture, i-micro-morphological lip ye-shear interface, kunye nomphezulu wesampuli.
I-Macroscopic kunye ne-microscopic fracture morphologies ye-20MnTiB imizekelo yebholithi yamandla aphezulu kwiindawo ezahlukeneyo ezifaniswayo ze-corrosion (500×): (a) akukho mhlwa; (b) ixesha eli-1; (c) 20 ×; (d) 200 ×; (e) pH3.5; (f) pH7.5; (g) 50°C.
Inokubonwa kumfanekiso wesi-4 ukuba ukwaphuka kwe-20MnTiB yoxinzelelo oluphezulu lwe-bolt corrosion specimen phantsi kweemeko ezahlukeneyo zokubola okufanisiweyo kubonisa ukuphuka kwekomityi eqhelekileyo. Xa kuthelekiswa ne-specimen engabonakaliyo (Umfanekiso we-4a), indawo ephakathi kwendawo yefiber crack incinci. , indawo yomlomo we-shear inkulu.Oku kubonisa ukuba iipropati ze-mechanical of the material zonakaliswe kakhulu emva kokugqwala.Ngokunyuka koxinzelelo lwesisombululo esifanisiweyo, imingxuma kwindawo ye-fiber kwindawo yokwaphuka yanda, kwaye i-seams ecacileyo yokukrazula ibonakala. isampuli, kwaye kwakukho ezininzi iimveliso zomhlwa phezu komhlaba.isampulu.
Kucatshulwa kwi-Figure 3d ukuba kukho ukuqhekeka okucacileyo kwi-corrosion layer kwi-surface yesampuli, engenalo impembelelo efanelekileyo yokukhusela kwi-matrix. Kwisisombululo se-corrosion esifanisiweyo se-pH 3.5 (Umfanekiso we-4e), umphezulu wesampuli ugxininiswe kakhulu, kwaye indawo yefiber ephakathi ngokucacileyo incinci. , Kukho inani elikhulu leengqungquthela ezingaqhelekanga zokukrazula kumbindi wendawo yefiber.Ngokonyuka kwexabiso le-pH yesisombululo sokutya okufanisiweyo, indawo yokukrazula kwindawo yefiber ephakathi kweqhekeza iyancipha, umgodi uyancipha ngokuthe ngcembe, kwaye ubunzulu bomgodi buyancipha ngokuthe ngcembe.
Xa ubushushu bonyuka ukuya kuma-50 ° C (umzobo 4g), indawo yomlomo wokucheba yokwaphuka kwesampulu yayiyeyona inkulu, imingxuma kwindawo yefiber esembindini yanda kakhulu, kwaye ubunzulu bomngxuma banda, kwaye ujongano phakathi komphetho womlomo wokucheba kunye nomphezulu wesampulu yanda. Iimveliso ze-Corrosion kunye nemingxuma ziye zanda, nto leyo eqinisekisa indlela enzulu ye-corrosion ye-substrate eboniswe kwi-Fig. 3f.
Ixabiso le-pH yesisombululo se-corrosion liya kubangela umonakalo kwiipropati zemishini ye-20MnTiB iibholiti zamandla aphezulu, kodwa umphumo awubalulekanga. Kwisisombululo se-corrosion ye-pH 3.5, inani elikhulu leemveliso ze-flocculent okanye iinaliti ezifana ne-corrosion zisasazwa kumphezulu wesampuli, kunye ne-corrosion, i-corrosion ye-corrosion ekhoyo i-substrate ecacileyo yokukhusela i-crack ecacileyo. imigodi ye-corrosion kunye nenani elikhulu lemveliso ye-corrosion kwi-morphology ye-microscopic ye-sample fracture.Oku kubonisa ukuba ukukwazi kwesampulu ukuxhathisa i-deformation ngamandla angaphandle kuncitshiswe kakhulu kwindawo ene-acidic, kwaye iqondo loxinzelelo lokuthambekela kwe-corrosion yezinto landa kakhulu.
Isisombululo somhlwa sokuqala esilinganisiweyo sasinempembelelo encinci kwiimpawu zoomatshini zeesampulu eziphezulu zamandla, kodwa njengoko uxinaniso lwesisombululo esilinganisiweyo se-corrosion senyuke saya kumaxesha angama-20 eso sisombululo somhlwa owenziweyo, iimpawu zomatshini zeesampulu zonakaliswe kakhulu, kwaye kwakukho ukubola okucacileyo kwi-fracture microstructure. imingxunya, iintanda zesibini kunye neemveliso ezininzi zokuhlwa.Xa i-corrosion solution efanisiweyo yoxinaniso yanda ukusuka kumaxesha angama-20 ukuya kumaxesha angama-200 oxinaniso lwesisombululo se-corrosion yasekuqaleni, umphumo wesisombululo se-corrosion concentration kwiipropati ze-mechanical of the material was weak.
Xa ubushushu obufanisiweyo bomhlwa bungama-25℃, amandla esivuno kunye namandla okuqina kwe20MnTiB imizekelo yebholithi yokuqina ayitshintshi kakhulu xa ithelekiswa nesampulu engagqwaliswanga. Nangona kunjalo, phantsi komgangatho owenziweyo wobushushu obuyi-50 °C, amandla okuqina kunye nokwandiswa kwesampulu yesampulu yehle kakhulu, iqondo lesampulu liye lancipha kakhulu, lehla kakhulu. umlebe wawungowona mkhulu, kwaye kwakukho i-dimples kwindawo ye-fiber ephakathi.Ukwanda ngokuphawulekayo, ubunzulu bomgodi banda, iimveliso zomhlwa kunye nemigodi ye-corrosion yanda.Oku kubonisa ukuba ubushushu be-synergistic corrosion bume bunempembelelo enkulu kwiipropati zomatshini ze-bolts eziphezulu, ezingabonakali kwiqondo lokushisa, kodwa kubaluleke ngakumbi xa ubushushu bufikelela kwi-50 ° C.
Emva kovavanyo olukhawulezileyo lwe-corrosion lwangaphakathi olulinganisa indawo ye-atmospheric e-Chongqing, amandla okuqina, amandla emveliso, ukunyusa kunye nezinye iiparamitha ze-20MnTiB iibholiti zamandla aphezulu zancitshiswa, kunye nomonakalo ocacileyo woxinzelelo. emigodini, kulula ukwenza umonakalo ocacileyo weplastiki kwiibholiti zokuqina okuphezulu, ukunciphisa amandla okumelana nokuguqulwa kwamandla angaphandle, kunye nokunyusa utyekelo lokurhweba koxinzelelo.
Li, G., Li, M., Yin, Y. & Jiang, S. Uphononongo loMfuniselo kwiipropathi zebholithi zokuqina okuphezulu ezenziwe ngentsimbi eyi-20MnTiB kwiqondo lobushushu eliphakamileyo.jaw.Civil engineering.J. 34, 100-105 (2001).
U-Hu, J., Zou, D. & Yang, Q. Uhlalutyo lokungaphumeleli kwe-fracture ye-20MnTiB yentsimbi ye-bolts yamandla aphezulu e-rails.unyango lokushisa.Metal.42, 185-188 (2017).
Catar, R. & Altun, H. Uxinzelelo lwe-corrosion cracking behavior of Mg-Al-Zn alloys phantsi kweemeko ezahlukeneyo ze-pH ngendlela ye-SSRT.Open.Chemical.17, 972-979 (2019).
Nazer, AA et al.Iziphumo ze-glycine kwi-electrochemical kunye noxinzelelo lwe-corrosion cracking behavior of Cu10Ni alloy in sulfide-contaminated brine.Industrial Engineering.Chemical.reservoir.50, 8796-8802 (2011).
I-Aghion, E. & Lulu, N. Iipropati ze-Corrosion ze-die-cast magnesium alloy MRI230D kwi-Mg (OH) 2-saturated 3.5% ye-NaCl isisombululo.alma mater.character.61, 1221-1226 (2010).
Zhang, Z., Hu, Z. & Preet, MS Impembelelo ye-chloride ion kwi-static kunye noxinzelelo lwe-corrosion behavior ye-9Cr martensitic steel.surf.Technology.48, 298-304 (2019).
I-Chen, i-X., i-Ma, i-J., i-Li, i-X., i-Wu, i-M. & iNgoma, i-B. Impembelelo ye-Synergistic ye-SRB kunye nobushushu kuxinzelelo lwe-corrosion cracking ye-X70 yentsimbi kwisisombululo sodaka lolwandle olwenziweyo. Chin.Socialist Party.coros.Pro.39, 477–484 (2019).
U-Liu, J., Zhang, Y. & Yang, S. Uxinzelelo lwe-corrosion behavior ye-00Cr21Ni14Mn5Mo2N insimbi engenasici emanzini olwandle.physics.thatha i-exam.test.36, 1-5 (2018).
Lu, C. Uphononongo olulibazisekileyo lokwaphuka kwebhulorho yokuqina okuphezulu kweebholithi.umhlathi.Isikolo semfundo.rail.science.2, 10369 (2019).
U-Ananya, B. Uxinzelelo lwe-corrosion cracking ye-duplex stainless steels kwi-caustic solutions.Doctoral Dissertation, Atlanta, GA, USA: Georgia Institute of Technology 137-8 (2008)
I-Sunada, S., Masanori, K., Kazuhiko, M. & Sugimoto, K. Iziphumo ze-H2SO4 kunye ne-naci concentrations kwi-stress corrosion cracking ye-SUS304 insimbi engenasici kwi-H2SO4-NaCl i-aqueous solution.alma mater.trans.47, 364-370 (2006).
I-Merwe, i-JWVD Impembelelo yokusingqongileyo kunye nezixhobo kuxinzelelo lwe-corrosion cracking yentsimbi kwi-H2O/CO/CO2 isisombululo.Inter Milan.J. Koros.2012, 1-13 (2012).
U-Ibrahim, M. & Akram A. Iziphumo zebicarbonate, ubushushu kunye ne-pH kwi-passivation ye-API-X100 yentsimbi yombhobho kwisisombululo samanzi aphantsi komhlaba.In IPC 2014-33180.
Shan, G., Chi, L., Ingoma, X., Huang, X. & Qu, D. Impembelelo yobushushu kuxinzelelo lwe-corrosion cracking susceptibility of austenitic stainless steel.coro.be ngokuchasene ne.Technology.18, 42-44 (2018).
Han, S. I-Hydrogen-eyenziwe ukulibaziseka kokuziphatha kokuphuka kweentsimbi ezininzi eziphezulu zokuqina (iYunivesithi yaseKunming yeSayensi kunye neTeknoloji, i-2014).
Zhao, B., Zhang, Q. & Zhang, M. Stress corrosion mechanism of GH4080A alloy for fasteners.cross.companion.Hey.treat.41, 102–110 (2020).