Hydrogen embrittlement brittle rupture tsis ua hauj lwm yog hais txog atomic hydrogen nkag mus rau sab hauv ntawm 316 stainless hlau yeeb nkab matrix raws li kev ua haujlwm tshwj xeeb. Hydrogen accumulates ntawm grain ciam teb, dislocations thiab micro- tsis xws luag nyob rau hauv cov khoom, tsim nyob rau hauv hydrogen siab thiab txo cov binding quab yuam ntawm cov hlau siv lead ua qauv. Nyob rau hauv qhov kev txiav txim ntawm lub siab sab hauv thiab sab nraud tensile kev ntxhov siab, cov kab nrib pleb me me tshwm sim thiab nthuav dav hauv cov yeeb nkab phab ntsa yam tsis muaj qhov pom tseeb ntawm cov yas deformation ntawm macroscopic nto, nws thiaj li ua rau nkig tawg thiab nruab nrab ntawm lub raj cua sov. Qhov kev ua tsis tiav no muaj zog heev sai sai thiab tsis muaj kev cia siab, feem ntau tshwm sim hauv cov kav dej nrog kev kho mob, kev tiv thaiv cathodic thiab hydrogen evolution corrosion ib puag ncig.
1. Hydrogen Permeation thiab Embrittlement Crack Propagation Mechanism
Nyob rau hauv acidic pickling nruab nrab los yog galvanic corrosion cathode cov tshuaj tiv thaiv, hydrogen ions tau txais electrons los tsim nascent atomic hydrogen nrog lub peev xwm nkag mus tau zoo heev. Cov me me - qhov loj ntawm hydrogen atoms tuaj yeem yooj yim dhau los ntawm cov zaj duab xis passive ntawm stainless hlau nto thiab diffuse mus rau hauv cov hlau lattice. Ib tug loj tus naj npawb ntawm hydrogen atoms sib sau ua ke nyob rau hauv micro voids thiab grain ciam teb, combining rau hauv hydrogen molecules thiab tsim loj loj expansion siab. Lub caij no, hydrogen txo cov intergranular bonding zog ntawm stainless hlau. Thaum cov kev ntxhov siab ua ke ntawm sab hauv hydrogen siab thiab pipeline hoop tensile stress tshaj cov khoom tawg toughness, intergranular los yog transgranular tawg daim ntawv thiab nthuav instantly. Tsis zoo li kev ntxhov siab corrosion cracking tsav los ntawm chloride ions, hydrogen embrittlement kev puas tsuaj yog dominated los ntawm sab hauv hydrogen intrusion es tsis yog sab nraud nruab nrab electrochemical etching.
2. Tej yam hauj lwm ua rau Hydrogen Embrittlement puas
Weld heat-affected zones with dense dislocations and more crystal defects, which are prone to hydrogen enrichment;
Cov kav dej tau raug xaiv thiab descaling yam tsis muaj kev tshem tawm hydrogen kom huv si;
Cathodic tiv thaiv thaj chaw ntawm cov kav dej uas txuas ntxiv hydrogen evolution cov tshuaj tiv thaiv tshwm sim ntawm cov hlau nto;
Txias- ua hauj lwm khoov lub luj tshib nrog siab residual nyob rau hauv kev ntxhov siab thiab siab hydrogen trapping efficiency;
Hauv zos pitting corrosion pits qhov twg microenvironment occluded tsis tu ncua ua hydrogen atoms.
3. Core Inducing Factors Accelerating Hydrogen Embrittlement Failure
Acid pickling descaling txheej txheem tsis muaj passivation thiab dehydrogenation ci txheej txheem tom qab ua haujlwm;
Kev teeb tsa tsis raug ntawm kev tiv thaiv cathodic tam sim no ua rau muaj kev hloov pauv hydrogen ntau dhau;
Qhov nruab nrab muaj cov acidic Cheebtsam, thiab cathode hydrogen evolution tshwm sim thaum lub sij hawm ntev - cov tshuaj tiv thaiv corrosion;
Lub raj xa dej muaj lub zog ua haujlwm ntau dhau thiab muaj zog tensile siab, uas muab lub zog tsav rau kev tawg;
Cov ntaub ntawv muaj ntau yam tsis xws luag xws li inclusions thiab pores, uas ua hydrogen aggregation ntxiab.
4. Tag nrho -Txuas Kev Tiv Thaiv thiab Tswj Kev Ntsuas Kev Ntsuas
① Ntxiv qis -concentration hydrogen recombination inhibitor thaum lub sijhawm ua haujlwm pickling
Txo cov tiam ntawm atomic hydrogen ntawm cov hlau nto los ntawm qhov chaw.
② Siv cov kev kho cua sov dehydrogenation thiab ua kom tiav cov yeeb yaj kiab passivation tom qab pickling thiab vuam
Force hydrogen hauv cov khoom kom khiav tawm thiab rov tsim kho cov txheej txheem tiv thaiv passive.
③ Ua kom zoo tshaj cathodic tiv thaiv qhov muaj peev xwm tsis nruj me ntsis kom tsis txhob dhau - tiv thaiv hydrogen evolution
Tswj cov tshuaj tiv thaiv cathode nyob rau hauv qhov chaw nyab xeeb yam tsis muaj dej nag lossis dej ntau dhau.
④ Txwv kev tsim kev ua haujlwm siab kom txo qis tensile kev ntxhov siab ntawm cov yeeb nkab phab ntsa matrix
Txiav cov neeg kho tshuab tsav tsheb rau kev pib tawg.
⑤ Ua tiav ultrasonic microscopic flaw nrhiav pom ntawm qhov tseem ceeb siab -cov kabmob cov kav dej tsis tu ncua
Nrhiav zais hydrogen-induced microcracks ua ntej nkag mus rupture.
5. Kev Tiv Thaiv Cov Teeb Meem Sib piv
表格
| Kev Kho Mob & Kev Ua Haujlwm Hom | Hydrogen Embrittlement Risk | Daim ntawv thov tswv yim |
|---|---|---|
| Direct pickling yam tsis muaj dehydrogenation + tshaj -ntau qhov kev tiv thaiv cathodic + kev ua haujlwm siab | Sudden brittle cracking tshwm sim nyob rau hauv lub sij hawm luv luv | Nres ua haujlwm rau dehydrogenation ci thiab kho cov kev tiv thaiv kev tiv thaiv |
| Pickling nrog hydrogen suppression + post-txheej txheem dehydrogenation kho + standardized tiv thaiv muaj peev xwm | Zoo thaiv hydrogen intrusion thiab sab hauv tawg propagation | Txuj kev tiv thaiv-hydrogen embrittlement specification rau pickling thiab tiv thaiv stainless hlau cua sov pipelines |
| Hauv -situ hydrogen concentration xyuas + post-weld heat treatment + periodic siab- rhiab heev flaw detection | Tsis tshua muaj brittle fracture muaj kev nyab xeeb | Cov txheej txheem nyiam rau cov txheej txheem acidic thiab cathodically tiv thaiv cua sov raj raj tshuab |
Xaus
Hydrogen embrittlement brittle rupture ntawm 316 stainless hlau cua sov raj yog tshwm sim los ntawm nascent hydrogen nkag mus rau hauv cov hlau sab hauv kom sib sau ua ke thiab tsim kom muaj siab, uas induces ceev nrooj propagation nyob rau hauv tensile kev nyuaj siab. Cov kev tiv thaiv tseem ceeb muaj xws li inhibiting hydrogen ntau lawm thaum lub sij hawm tshuaj ntxuav, npaj dehydrogenation ci thiab passivation kho, standardizing cathodic tiv thaiv kev tsim kho, tswj pipeline load kev nyuaj siab thiab ntxiv dag zog rau microscopic flaw soj ntsuam. Tag nrho- txheej txheem kaw- voj kev tswj xyuas cov kav dej tshuaj, tiv thaiv- kev tiv thaiv kev tiv thaiv kev tiv thaiv kab mob thiab cov khoom siv tshuaj xyuas ib ntus tuaj yeem tshem tawm qhov kev puas tsuaj ntawm kev nyab xeeb tshwm sim los ntawm hydrogen embrittlement ntawm cov kav dej cua sov.
