Qhov cuam tshuam ntawm nickel

Cov nyhuv ntawm nickel rau cov ntaub so ntswg
Nickel yog ib yam khoom uas ruaj khov austenite thiab nthuav dav austenite theem cheeb tsam. Txhawm rau kom tau txais ib qho qauv austenite, qhov tsawg kawg nkaus nickel cov ntsiab lus yuav tsum tau thaum cov hlau muaj 0.1 feem pua ​​carbon thiab 18 feem pua ​​chromium yog li 8 feem pua, uas yog cov ntsiab lus ntawm cov nto moo tshaj plaws 18-8 chromium nickel austenitic stainless hlau. Nyob rau hauv austenitic stainless hlau, raws li cov ntsiab lus nickel nce, residual ferrite tuaj yeem raug tshem tawm tag nrho thiab txo qis σ Qhov nyiam ntawm theem tsim; Nyob rau tib lub sijhawm, qhov kub ntawm Martensite hydrocarbon hloov pauv txo qis, txawm tias tsis muaj λ → M theem kev hloov pauv, tab sis qhov nce ntawm cov ntsiab lus nickel yuav txo cov solubility ntawm carbon nyob rau hauv austenitic stainless hlau, yog li pab txhawb txoj kev nyiam rau carbide nag lossis daus.
Cov nyhuv ntawm nickel rau kev ua haujlwm
Qhov cuam tshuam ntawm npib tsib xee rau cov khoom siv ntawm austenitic stainless hlau, tshwj xeeb tshaj yog chromium nickel austenitic stainless hlau, feem ntau txiav txim siab los ntawm kev cuam tshuam ntawm npib tsib xee rau kev ruaj ntseg ntawm austenite. Tsis pub dhau qhov ntau ntawm cov ntsiab lus npib tsib xee hauv cov hlau uas yuav raug hloov pauv Martensite, nrog rau cov ntsiab lus npib tsib xee, lub zog ntawm cov hlau txo thiab plasticity nce. Chromium nickel austenitic stainless hlau nrog ruaj khov austenite qauv muaj zoo heev toughness (xws li kub tsis tshua muaj kub toughness), yog li nws yuav siv tau raws li tsis tshua muaj kub hlau, Nws yog paub zoo tias rau chromium manganese austenitic stainless hlau nrog ruaj austenite qauv, ntxiv ntawm npib tsib xee. tuaj yeem txhim kho nws qhov toughness ntxiv. Nickel kuj tseem tuaj yeem txo qis kev ua haujlwm txias txias ntawm austenitic stainless hlau, uas yog vim muaj kev ruaj ntseg ntawm austenite, txo lossis txawm tias tshem tawm Martensite hloov pauv hauv cov txheej txheem ua haujlwm txias. Nyob rau tib lub sijhawm, kev ua haujlwm txias ua haujlwm ntawm austenite nws tus kheej tsis pom tseeb, thiab kev cuam tshuam ntawm kev ua haujlwm txias hardening nyiam ntawm stainless hlau. Nickel txo qhov txias ua haujlwm hardening tus nqi ntawm austenitic stainless hlau, txo cov chav tsev kub thiab tsis tshua muaj kub lub zog ntawm hlau, thiab txhim kho plasticity, nce nyob rau hauv cov ntsiab lus npib tsib xee muaj txiaj ntsig rau qhov txias ua hauj lwm formability ntawm austenitic stainless hlau, thiab nce cov ntsiab lus nickel tuaj yeem ua tau. txo lossis txawm tshem tawm cov corrosion ntawm 18-8 thiab 17-14-2 hom chromium nickel austenitic stainless hlau δ Ferrite, yog li txhim kho nws cov khoom kub ua haujlwm, tab sis, δ Qhov txo qis ntawm ferrite tsis zoo rau cov weldability ntawm cov hlau no. , uas yuav ua rau kom muaj kev nyiam ntawm vuam kub tawg xov hlau. Tsis tas li ntawd, npib tsib xee kuj tseem tuaj yeem txhim kho kev ua haujlwm kub ntawm chromium manganese nitrogen (chromium manganese nickel nitrogen) austenitic stainless hlau, yog li txhim kho cov txiaj ntsig ntawm cov hlau. Nyob rau hauv austenitic stainless hlau, qhov sib ntxiv ntawm npib tsib xee thiab qhov nce ntawm cov ntsiab lus npib tsib xee ua rau qhov nce ntawm cov thermodynamic stability ntawm cov hlau, Yog li, austenitic stainless hlau muaj cov xeb zoo dua thiab tsis kam mus rau oxidizing xov xwm, thiab raws li cov ntsiab lus nickel nce, kev ua tau zoo. ntawm kev txo cov xov xwm yog ntxiv txhim kho. Nws yog tsim nyog taw qhia tias npib tsib xee tseem yog tib lub ntsiab lus tseem ceeb los txhim kho kev ua haujlwm ntawm austenitic stainless hlau rau transgranular kev nyuaj siab corrosion nyob rau hauv ntau yam xov xwm. Kev cuam tshuam ntawm npib tsib xee rau corrosion kuj ntawm austenitic stainless hlau nyob rau hauv ntau yam acid media yuav tsum tau taw qhia tias nyob rau hauv tej yam kev mob nyob rau hauv high-temperature thiab high-pressure dej, qhov nce ntawm cov ntsiab lus nickel yuav ua rau kom cov hlau thiab alloy rau intergranular. kev ntxhov siab corrosion, tab sis qhov kev tsis zoo no yuav txo qis lossis txwv vim qhov nce ntawm chromium cov ntsiab lus hauv cov hlau thiab hlau. Nrog rau qhov nce ntawm cov ntsiab lus npib tsib xee hauv daim npav sib nqus austenitic stainless hlau, cov ntsiab lus tseem ceeb ntawm cov pa roj carbon monoxide yuav txo qis, uas yog, qhov cuam tshuam ntawm cov hlau rau intergranular corrosion yuav nce. Raws li kev tiv thaiv rau pitting corrosion thiab Crevice corrosion ntawm austenitic stainless hlau, cov nyhuv ntawm npib tsib xee tsis tseem ceeb, thiab ntxiv rau, npib tsib xee kuj txhim kho qhov kub-kub oxidation tsis kam ntawm austenitic stainless hlau.