Hydrogen embrittlement brittle fracture yog hais txog hydrogen atoms nkag mus rau sab hauv ntawm titanium matrix nyob rau hauv ib qho kub thiab nruab nrab ib puag ncig. Hydrogen reacts nrog titanium los ua brittle titanium hydride precipitates, uas rhuav tshem qhov txuas ntxiv ntawm hlau microstructure. Nyob rau hauv lub siab sab hauv thiab thermal kev nyuaj siab, nkig nkig sprouts sprout thiab nthuav sai sai nyob rau hauv lub yeeb nkab phab ntsa yam tsis pom tseeb yas deformation ntawm qhov chaw, nws thiaj li ua rau nkig rupture thiab nruab nrab to ntawm titanium cua sov raj. Qhov kev ua tsis tiav no yog los ntawm hydrogen-induced cov khoom intrinsic brittleness puas tsuaj, uas nquag tshwm sim nyob rau hauv titanium pipelines pab nyob rau hauv pickling ib puag ncig, ntub hydrogen- muaj nruab nrab thiab cathodic tiv thaiv systems.
1. Hydrogen Penetration thiab Embrittlement Mechanism
Titanium muaj peev xwm nqus hydrogen muaj zog ntawm qhov kub thiab txias. Thaum cov raj xa mus rau cov kua qaub kua qaub los yog hydrogen- cov txheej txheem nplua nuj, hydrogen ions nyob rau hauv nruab nrab tau txais electrons thiab tig mus rau hauv atomic hydrogen. Cov me me - loj hydrogen atoms tau yooj yim dhau los ntawm titanium passivation zaj duab xis thiab diffuse mus rau hauv cov hlau lattice. Raws li hydrogen concentrations mus rau saturation, koob -zoo li brittle titanium hydride theem sib cais tawm raws li cov ciam teb. Cov theem hydride no muaj qhov tsis tshua muaj zog thiab dhau los ua qhov chaw tawg. Nyob rau hauv tensile kev nyuaj siab generated los ntawm lub siab bearing thiab kub hloov, cov kab nrib pleb propagate raws hydride faib chaw ntawm ib tug ceev ceev ceev, ua rau cleavage puas nrog yuav luag tsis muaj ductile deformation. Sib txawv ntawm galvanic corrosion thiab crevice corrosion uas yog cov khoom tawg, hydrogen embrittlement yog cov txheej txheem brittleness deterioration los ntawm cov khoom siv sab hauv, thiab cov yeeb nkab lub cev tsis muaj qhov pom tseeb poob ua ntej tawg.
2. Tej yam hauj lwm ua rau Hydrogen Embrittlement puas
Cov kav xa dej tau ntim rau hauv cov kua qaub kua qaub thaum lub sij hawm tshuaj ntxuav thiab kev tsim kho passivation;
Cov yeeb nkab ntu txuas nrog cathodic los tiv thaiv- cov khoom siv tiv thaiv corrosion uas muaj peev xwm tiv thaiv ntau dhau;
Cov kav dej tuag nyob qhov twg hydrogen- muaj qhov nruab nrab yog kaw thiab hydrogen tsis tu ncua dissolves thiab accumulates;
Welded pob qij txha nrog xoob grain qauv thiab sai hydrogen diffusion tus nqi;
Tsawg- qhov kub thiab txias kaw qhov chaw uas hydrogen solubility poob thiab hydride precipitates hauv ntau.
3. Core Inducing Factors Accelerating Hydrogen Embrittlement
Kev tswj tsis tau lub sij hawm pickling thiab acid concentration thaum lub sij hawm ntawm -site pipeline tu, ua rau hydrogen nqus dej ntau dhau;
Kev teeb tsa tsis zoo ntawm kev tiv thaiv cathodic tam sim no, ua rau muaj kev tiv thaiv ntau dhau thiab yuam hydrogen evolution;
Ntev - lub sij hawm kaw yam tsis muaj qhov khoob hydrogen- nplua nuj nruab nrab hauv cov kav dej kom tsis txhob muaj hydrogen enrichment;
Ua haujlwm nruab nrab muaj hydrogen sulfide, nascent hydrogen thiab lwm yam khoom uas yooj yim rau dissociate hydrogen atoms;
Tsis muaj dehydrogenation tshav kub kho tom qab vuam thiab pickling kom tshem tawm cov yaj hydrogen hauv cov khoom.
4. Tag nrho -Txuas Kev Tiv Thaiv thiab Tswj Kev Ntsuas Kev Ntsuas
① Tsim cov qauv luv luv - lub sij hawm pickling txheej txheem nrog corrosion inhibitor ntxiv nruj me ntsis
Txwv acid soaking ntev kom txo hydrogen permeation rau hauv titanium substrate.
② Precisely kho cathodic tiv thaiv muaj peev xwm kom tsis txhob overprotection hydrogen evolution cov tshuaj tiv thaiv
Teem lub peev xwm sab sauv txhawm rau thaiv kev tsim hydrogen los ntawm qhov chaw.
③ Npua thiab hloov qhov nruab nrab seem hauv cov kav xa dej tom qab ntev - lub sijhawm kaw haujlwm
Tshem tawm cov khoom siv hydrogen los tiv thaiv hydride nag lossis daus ntawm qhov kub thiab txias.
④ Siv qis-kub dehydrogenation annealing kho tom qab vuam thiab kua qaub ntxuav
Tsav tawm cov dej tsis sib xws hauv cov titanium hlau lattice.
⑤ Kev tshuaj xyuas cov khoom siv tsis tu ncua txhawm rau txheeb xyuas hydride nag lossis daus℃ntawm cov yeeb nkab tseem ceeb
Hloov cov khoom hnyav ua ntej ua ntej ua ntej pob txha tsis ua haujlwm.
5. Kev Tiv Thaiv Cov Teeb Meem Sib piv
表格
| Kev ua haujlwm & kev tiv thaiv hom | Hydrogen Embrittlement Risk | Daim ntawv thov tswv yim |
|---|---|---|
| Unrestricted pickling + overprotection + tsis muaj dehydrogenation kho | Sudden brittle cracking tshwm sim tom qab ob peb lub voj voog ua haujlwm | Txiav cov yeeb nkab ua tsis tiav thiab ua tag nrho dehydrogenation tshav kub kho |
| Kev tswj xyuas kev tsim kho kev tsim kho + kev tiv thaiv muaj peev xwm + lub sijhawm nruab nrab hloov pauv | Zoo inhibit hydrogen absorption thiab hydride tiam | Txuj kev ua haujlwm tshwj xeeb rau kev tiv thaiv -corrosion titanium cua sov pipeline txij nkawm |
| Inhibitor tag nrho - txheej txheem ntxiv + tiag - lub sijhawm saib xyuas + kev tshawb pom metallographic tsis tu ncua | Tsis tshua muaj brittle fracture zais txaus ntshai | Cov txheej txheem nyiam rau cov khoom siv titanium nyob rau hauv ntev - cov tshuaj lom neeg nruab nrab ua haujlwm |
Xaus
Hydrogen embrittlement tsis ua hauj lwm ntawm titanium cua sov raj yog tshwm sim los ntawm hydrogen atom infiltration thiab titanium hydride nag lossis daus hauv matrix, uas txo cov khoom toughness thiab ua rau muaj kev ntxhov siab -induced sudden brittle fracture. Cov tswv yim tiv thaiv tseem ceeb suav nrog kev tswj xyuas cov pickling thiab tiv thaiv - kev tiv thaiv corrosion los txiav tawm hydrogen nkag channel, raws sij hawm tshem tawm hydrogen- nplua nuj nruab nrab, thiab tshem tawm cov hydrogen sab hauv los ntawm kev kho cua sov dehydrogenation. Kaw -Txoj kev tswj lub raj xa dej huv, tiv thaiv- kev txhim kho corrosion, kaw kev txij nkawm thiab kev tshuaj xyuas cov khoom tuaj yeem tiv thaiv kev puas tsuaj ntawm kev nyab xeeb tshwm sim los ntawm hydrogen embrittlement ntawm titanium cua sov raj.
