Hastelloy yog Ni-Mo alloy uas tsis tshua muaj carbon thiab silicon cov ntsiab lus, uas txo cov nag lossis daus ntawm carbides thiab lwm theem nyob rau hauv qhov chaw vuam thiab kub-tshuaj, yog li xyuas kom zoo weldability txawm nyob rau hauv lub xeev welded. Corrosion kuj. Raws li peb txhua tus paub, Hastelloy muaj kev tiv thaiv corrosion zoo heev hauv ntau yam kev tshaj tawm, thiab tuaj yeem tiv taus qhov corrosion ntawm hydrochloric acid ntawm txhua qhov kub thiab txias thiab txhua qhov kev xav tau nyob rau hauv ib txwm muaj siab. Nws muaj corrosion kuj zoo heev nyob rau hauv nruab nrab-concentration non-oxidizing sulfuric acid, ntau yam phosphoric acid, high-temperature acetic acid, formic acid thiab lwm yam organic acids, bromic acid thiab hydrogen chloride gas. Nyob rau tib lub sijhawm, nws tseem tiv taus corrosion los ntawm halogen catalysts. Yog li ntawd, Hastelloy feem ntau yog siv ntau yam roj av hnyav thiab cov txheej txheem tshuaj, xws li distillation thiab concentration ntawm hydrochloric acid; alkylation ntawm ethylbenzene thiab low-pressure carbonylation ntawm acetic acid thiab lwm yam txheej txheem ntau lawm. Txawm li cas los xij, nws tau pom nyob rau hauv daim ntawv thov kev lag luam ntawm Hastelloy tau ntau xyoo:
(1) Muaj ob qhov chaw rhiab heev nyob rau hauv Hastelloy alloy uas muaj kev cuam tshuam loj heev rau kev tiv thaiv intergranular corrosion: thaj chaw kub kub ntawm 1200 ~ 1300 ° C thiab nruab nrab kub cheeb tsam ntawm 550 ~ 900 ° C;
(2) Vim lub dendrite sib cais ntawm cov hlau weld thiab tshav kub-cuam tshuam cheeb tsam ntawm Hastelloy alloy, intermetallic theem thiab carbides precipitate raws li grain ciam teb, ua rau lawv rhiab heev rau intergranular corrosion;
(3) Hastelloy tsis zoo thermal stability ntawm nruab nrab kub. Thaum cov ntsiab lus hlau nyob rau hauv Hastelloy alloy poob qis dua 2%, lub alloy yog rhiab heev rau kev hloov ntawm β theem (uas yog, Ni4Mo theem, ib qho kev txiav txim intermetallic compound). Thaum cov hlau nyob hauv qhov kub ntawm 650 ~ 750 ℃ rau ntev me ntsis, β theem yog tsim tam sim. Lub hav zoov ntawm β theem txo cov tawv ntawm Hastelloy alloy, ua rau nws rhiab heev rau kev ntxhov siab corrosion, thiab txawm ua rau Hastelloy alloy Zuag qhia tag nrho kev kho cua sov) thiab Hastelloy cov cuab yeej tawg hauv qhov chaw pabcuam. Tam sim no, cov txheej txheem kev ntsuas tus qauv rau kev tiv thaiv intergranular corrosion ntawm Hastelloy alloys tsim los ntawm kuv lub teb chaws thiab lwm lub teb chaws hauv ntiaj teb yog cov txheej txheem kub npau npau hydrochloric acid, thiab txoj kev ntsuam xyuas yog txoj kev poob phaus. Txij li Hastelloy yog ib qho alloy resistant rau hydrochloric acid corrosion, ib txwm siab boiling hydrochloric acid txoj kev yog heev insensitive mus ntsuam xyuas lub intergranular corrosion nyiam ntawm Hastelloy. Cov koom haum tshawb fawb hauv tsev siv cov txheej txheem kub-kub hydrochloric acid los kawm Hastelloy alloys thiab pom tias qhov kev tiv thaiv corrosion ntawm Hastelloy alloys tsis tsuas yog nyob ntawm nws cov tshuaj muaj pes tsawg leeg, tab sis kuj ntawm nws cov txheej txheem thermal ua. Thaum cov txheej txheem thermal ua tsis raug, tsis yog tsuas yog siv lead ua nplej ntawm Hastelloy alloys loj hlob, tab sis kuj yog theem σ nrog siab Mo yuav ua rau nag lossis daus ntawm cov nplej. , lub grain ciam etching qhov tob ntawm coarse-grained phaj thiab cov phaj ib txwm yog hais txog ob npaug.
Post lub sij hawm: May-15-2023
