Siab zog nkoj phaj nro stratification tswj
Nyob rau hauv xyoo tas los no, nrog rau kev loj hlob sai ntawm Tuam Tshoj txoj kev lag luam shipbuilding, ntau lub tsev steel mills yog nyob rau hauv txoj kev loj hlob thiab zus tau tej cov high-strength nkoj phaj steel, xws li Baosteel, Wisco, thiab lwm yam., tab sis high-lub zog nkoj phaj yuav tshwm sim vim yog. tensile test tom qab qhov chaw tawg tawg, uas yog, nro stratification thiab seem phenomenon. Cov txiaj ntsig tau pom tias tsis muaj qhov xoob xoob xoob, kev sib cais ntawm C thiab Mn cov ntsiab lus hauv nruab nrab, strip MnS suav nrog, thiab kev sib xyaw ua ke ntawm MnS, Al2O3 thiab TiO2 nyob rau hauv nruab nrab ntawm lub zog siab nkoj phaj thickness yog qhov ua rau muaj kev sib txhuam delamination.
Cov kev tswj xyuas cuam tshuam yog:
1. Txo S cov ntsiab lus
Nkoj phaj hlau yog hom hlau manganese siab, thaum Mn cov ntsiab lus yog li ntawm 1. tswj hauv qab no 0.005%.
2. Pub cov silicon calcium hlau
Cov sulfide inclusions, tshwj xeeb tshaj yog cov MnS inclusions, tuaj yeem denatured los ntawm kev pub cov silicon-calcium hlau, thiab lawv cov duab tuaj yeem tswj tau ua kheej kheej, uas tsis tshua muaj kev phom sij rau cov hlau, thiaj li txo qhov nro delamination tshwm sim.
3. Optimize nruam casting
1) Superheat
Nyob rau hauv cov ntaub ntawv uas tsis muaj dej khov ntawm lub nozzle, lub tuab phaj casting tshuab yuav tsum tau nchuav nrog tsawg superheat kom deb li deb tau, thiab lub superheat yog tswj ntawm 15-25 degree .
2) rub ceev
Raws li qhov kev pom zoo tsis cuam tshuam rau cov zis, qhov rub nrawm yuav tsum tsis txhob loj dhau, thiab qhov rub nrawm yuav tsum tswj ntawm 0.9-1.1m/min.
3) Secondary txias
Lub zog txias txias tuaj yeem ua rau qeeb ntawm txoj kev loj hlob ntawm cov kab nrib pleb, ua kom cov equiaxed siv lead ua tus nqi, thiab txo qhov tshwm sim ntawm qhov chaw sib cais thiab qhov chaw porosity.
4) Electromagnetic stirring
Kev siv cov cua txias electromagnetic stirring tuaj yeem txhim kho qhov zoo ntawm cov billet, txo qhov kev sib cais ntawm txhua lub caij thiab txo qhov chaw xoob ntawm lub billet.
4. optimize cua sov thiab tswj dov thiab txias
1) Kub kub
Qhov sov so ntau dua thiab lub sijhawm ntub dej ntev dua yog qhov tsim nyog rau qhov sib txawv ntawm cov khoom sib cais, thiab qhov qhib dov tuaj yeem tswj tau ntawm 1100-1180 degree .
2) Tswj dov thiab txias
Los ntawm kev nce tus nqi txo, qhov kev ntxhov siab permeability tuaj yeem nce ntxiv, cov teeb meem uas tsim tawm hauv cov hlau nplaum tuaj yeem raug welded, thiab cov lamination tsis xws luag ntawm cov phaj hlau tuaj yeem txo.
Thaum lub caij txias, C atom nyob rau hauv Mn pluag cheeb tsam tuaj yeem ua tiav qhov kev hloov pauv ntawm austenite mus rau ferrite ua ntej nws yuav lig dhau mus rau thaj tsam Mn nplua nuj, thiab kev faib tawm ntawm ferrite thiab perlite tsis tshwm sim, thiab kev tsim ntawm banded qauv yog inhibited.
