Gas corrosion: txhais, nta thiab txoj kev los daws qhov teeb meem

2024 Tus sau: Howard Calhoun | [email protected]. Kawg hloov kho: 2023-12-17 10:28

Ntau qhov kev lag luam thiab kev tsim kho siv cov txheej txheem thev naus laus zis uas muaj cov roj sib tov. Qhov no tuaj yeem yog, piv txwv li, kev ua haujlwm ntawm cov khoom hauv qab propane burners lossis tsim kev tiv thaiv ib puag ncig thaum vuam kom cais cov haujlwm ntawm cov pa oxygen. Raws li qee qhov xwm txheej, cov txheej txheem zoo li no tuaj yeem ua rau muaj roj corrosion - tshwj xeeb, ntawm qhov kub siab lossis siab. Kev ua tshuaj lom neeg nce ntxiv, uas cuam tshuam tsis zoo rau cov qauv ntawm cov hlau thiab alloys. Yog li ntawd, cov txheej txheem tshwj xeeb tau tsim los tiv thaiv cov xwm txheej zoo li no thiab tawm tsam qhov tshwm sim ntawm corrosion ntawm hom no.

Kev txiav txim siab ntawm cov roj corrosion

Hom kev puas tsuaj corrosion no yog tshuaj lom neeg deformation ntawm cov hlau ntawm qhov kub thiab txias. Feem ntau, xws li phenomena muaj nyob rau hauv metallurgical, petrochemical thiab tshuaj industries. RauPiv txwv li, corrosion tuaj yeem tshwm sim thaum lub sij hawm tsim cov sulfuric acid, thaum lub sij hawm synthesis ntawm ammonia thiab tsim hydrogen chloride. Tsis tas li ntawd, roj corrosion ntawm cov hlau yog cov txheej txheem oxidative cov tshuaj tiv thaiv uas tshwm sim nyob rau hauv tej yam kev mob nrog ib tug tej yam humidity coefficient nyob rau hauv ib puag ncig huab cua. Txawm li cas los xij, tsis yog txhua lub roj tuaj yeem ua rau corrosion. Cov khoom sib xyaw ua ke tshaj plaws hauv qhov kev hwm no yog nitrogen oxides, sulfur dioxide, oxygen, hydrogen, thiab halogens. Raws li rau cov khoom ntawm kev puas tsuaj, ntxiv dag zog rau cov cub tawg thiab boilers, cov kav dej sib txuas, qhov chaw ntawm cov roj turbines, cov ntsiab lus ntawm cov cav combustion sab hauv thiab cov alloys uas raug kev kho cua sov hauv metallurgy.

txheej txheem nta

Thaum thawj theem ntawm cov tshuaj tiv thaiv, oxygen atoms yog chemisorbed rau ntawm hlau nto. Nws yog nyob rau hauv qhov tshwj xeeb ntawm kev sib cuam tshuam ntawm oxygen nrog cov hlau uas lub ntsiab feature ntawm no corrosion lies. Qhov tseeb yog tias cov tshuaj tiv thaiv muaj cov yam ntxwv ntawm kev sib cuam tshuam ionic thiab qhov no txawv ntawm cov txheej txheem tshuaj lom neeg hauv dioxide. Daim ntawv cog lus muaj zog dua vim tias cov pa atoms cuam tshuam los ntawm thaj chaw ntawm cov hlau atoms hauv qab. Tsis tas li ntawd, cov txheej txheem oxygen adsorption tshwm sim, thiab nyob rau hauv cov xwm txheej ntawm thermodynamic stability, chemisorption txheej tau hloov pauv sai sai rau hauv oxide zaj duab xis. Thaum kawg, roj corrosion tuaj yeem tsim cov ntsev, sulfides thiab oxides ntawm cov hlau. Qhov kev siv ntawm cov txheej txheem ntawm kev puas tsuaj corrosion yog cuam tshuam los ntawm cov khoom ntawm oxidizing tus neeg sawv cev (gaseous nruab nrab),microclimatic tsis (kub, siab thiab av noo), nrog rau lub xeev tam sim no ntawm cov tshuaj tiv thaiv cov khoom nws tus kheej.

Kev tiv thaiv roj corrosion los ntawm alloying

Ib txoj hauv kev zoo tshaj plaws ntawm kev tiv thaiv hlau los ntawm txhua yam txheej txheem corrosive. Txoj kev no yog los ntawm kev hloov cov khoom ntawm cov qauv ntawm cov hlau corroding. Nyob rau hauv nws tus kheej, alloying koom nrog kev hloov kho ntawm cov hlau los ntawm kev qhia cov khoom uas ua rau passivation ntawm nws cov qauv. Tshwj xeeb, tungsten, npib tsib xee, chromium, thiab lwm yam tuaj yeem siv tau, tshwj xeeb tshaj yog rau cov roj tiv thaiv corrosion, cov ntsiab lus yog siv los ua kom cov cua sov thiab cov cua sov ua haujlwm ntawm cov hlau. Cov txheej txheem alloying tuaj yeem ua tiav ob qho tib si los ntawm kev siv cov coatings tshwj xeeb thiab los ntawm immersing lub workpiece nyob rau hauv cov roj theem ntawm kev hloov cov khoom. Hauv ob qho tib si, qhov tsis kam ntawm cov hlau rau cov txheej txheem oxidative nce. Piv txwv li, txhawm rau kom txo qis tus nqi ntawm oxidation ntawm ib feem ntawm cov hlau ntawm 900 ° C, nws yog ib qho tsim nyog yuav tsum alloy nws nrog qib A1 alloy ntawm 3.5%, thiab rau plaub zaug txo, nrog rau A1 hloov kho ntawm 5.5%.

Tiv thaiv huab cua raws li kev tiv thaiv corrosion

Lwm cov txheej txheem los tiv thaiv cov hlau tsis muaj hlau thiab hlau los ntawm kev puas tsuaj los ntawm cov roj oxidation. Cov huab cua tiv thaiv tuaj yeem tsim los ntawm argon, nitrogen, thiab carbon media. Cov roj sib tov tshwj xeeb yog siv rau txhua qhov hlau. Piv txwv li, cam khwb cia hlau yog tiv thaiv los ntawm argon los yogcarbon dioxide tebchaw, thiab steel interacts zoo nrog hydrogen thiab nitrogen. Hauv kev saib xyuas cov kav dej loj, qhov kev tiv thaiv zoo li no yog siv thaum ua kev sib dhos ua haujlwm vuam. Hauv kev ua haujlwm tas li, kev tiv thaiv hluav taws xob ntawm cov hluav taws xob sib txuas tiv thaiv corrosion yog siv ntau dua, uas yog technically ua los ntawm semiconductors nrog cable circuits. Qhov no yog ib hom electrochemical anti-corrosion plhaub, uas suav nrog cov ntsiab lus ntawm anode-tiv thaiv galvanic tiv thaiv hauv cov qauv.

Kev siv tshuaj tiv thaiv corrosion tshav kub-resistant txheej

Txoj kev no kuj muaj nyob rau hauv kev txo tus nqi ntawm cov txheej txheem corrosion, tab sis ntawm tus nqi ntawm cov txheej txheem tshwj xeeb kub-resistant. Ib qho txheej txheem siv feem ntau rau kev siv hlau-aluminium thermal diffusion txheej yog hu ua thermochromizing. Ceramic-hlau ua cov hlau qhov chaw thiab cov qauv kuj muab kev tiv thaiv zoo. Qhov zoo ntawm xws li kev tiv thaiv roj corrosion tsis yog tsuas yog txhim khu kev qha thermal thiab mechanical txheej, tab sis kuj muaj peev xwm hloov pauv hloov pauv ntawm lub cev lub cev ntawm lub plhaub. Ob lub refractory oxides thiab hlau Cheebtsam xws li molybdenum thiab tungsten tuaj yeem siv los ua ib feem ntawm cov txheej txheem ua haujlwm.

Zaj lus

Cov kws tshaj lij tau koom nrog hauv lub koom haum tswj kev tiv thaiv kev tiv thaiv corrosion, tsim thiab pom zoo cov haujlwm rau cov khoom tshwj xeeb. Nyob rau hauv Russia, JSC Mosgaz yog ib lub tuam tsev loj tshaj plaws rau kev tiv thaiv cov roj network los ntawm corrosion. Cov neeg ua haujlwmntawm cov qauv no tau koom nrog kev pabcuam roj av, tswj xyuas qhov zoo ntawm cov chaw ua haujlwm. Hauv particular, lub koom haum ua haujlwm xws li kev teeb tsa ntawm cov khoom siv hluav taws xob tiv thaiv hluav taws xob, kev ntsuam xyuas kev phom sij ntawm cov kav dej hauv av, kev tshuaj xyuas qhov kev siv ntawm corrosiveness ntawm cov ntaub ntawv, thiab lwm yam. Rau feem ntau ntawm kev ua hauj lwm, cov khoom siv niaj hnub metrological yog siv los ua cov khoom siv. Ua kom raug thiab ua tiav tshuaj xyuas cov hom phiaj rau corrosion los ntawm nws.