Tsawg-Tsuas Toughness Optimization Technology thiab Adaptation Solutions rau High-Qhov siab thiab txias Regions rau National Standard Rails
Dab tsi yog qhov tseem ceeb ntawm cov tshuaj muaj pes tsawg leeg hloov ntsuas rau qis -kub toughness optimization ntawm lub teb chaws tus qauv rails?
Lub hauv paus tshuaj muaj pes tsawg leeg hloov ntsuas ntsuas rau qis -kub toughness optimization ntawm lub teb chaws tus qauv rails yogprecisely tswj cov ntsiab lus carbon thiab ntxiv microalloying ntsiabkom sib npaug lub zog thiab qis -kub toughness ntawm cov ntsia hlau. Cov ntsiab lus carbon yuav tsum tswj ntawm 0.65%-0.75%. Cov ntsiab lus carbon ntau dhau yuav txhim kho txoj kev tsheb ciav hlau tab sis txo qis -kub toughness, ua rau nkig tawg ntawm txoj kev tsheb ciav hlau ntawm qhov kub tsawg; Cov ntsiab lus qis carbon ntau dhau tsis tuaj yeem ua tau raws li qhov yuav tsum tau muaj zog ntawm txoj kev tsheb ciav hlau. Cov ntsiab lus ntxiv microalloying feem ntau suav nrog nickel, vanadium thiab niobium. Nickel tuaj yeem kho cov nplej thiab txhim kho qhov qis- qhov kub thiab txias cuam tshuam ntawm txoj kev tsheb ciav hlau, nrog rau cov nyiaj ntxiv tswj ntawm 0.2%-0.3%; vanadium thiab niobium tuaj yeem tsim carbonitrides, pin lis ciam teb thiab cuam tshuam kev loj hlob, nrog vanadium ntxiv nyiaj ntawm 0.03% -0.05% thiab niobium ntxiv nyiaj ntawm 0.01% -0.02%. Nyob rau tib lub sij hawm, cov ntsiab lus ntawm impurity ntsiab xws li sulfur thiab phosphorus yuav tsum nruj me ntsis tswj, nrog rau cov ntsiab lus sulfur tsawg dua los yog sib npaug rau 0.015% thiab phosphorus cov ntsiab lus tsawg dua los yog sib npaug rau 0.02%, tsis txhob cais cov impurity ntsiab ntawm cov ciam teb nplej thiab txo qis kub toughness. Kev kho tsheb ciav hlau muaj kev cuam tshuam lub zog Ntau dua lossis sib npaug rau 30J ntawm -40 degree, ntau dua li 15J ntawm cov tsheb ciav hlau.
Dab tsi yog cov ntsiab lus tseem ceeb ntawm cov txheej txheem kho cua sov rau qis -kub toughness optimization ntawm lub teb chaws tus qauv rails?
Cov txheej txheem kev kho cua sov tseem ceeb rau qis -kub toughness optimization ntawm lub teb chaws tus qauv rails yog siv cov txheej txheem sib xyaw ntawmtswj dov thiab tswj kom txias + qis-kub temperingtxhawm rau txhim kho microstructure ntawm txoj kev tsheb nqaj hlau. Cov txheej txheem tswj dov thiab tswj kev ua kom txias yog qhov tseem ceeb. Qhov kub dov yog tswj ntawm 850-900 degree, nrog ob-dav dov, thiab dov deformation yog tswj ntawm 30%-40% los ua kom cov nplej austenite. Tom qab dov, cov tshuaj tsuag txias tau txais yuav, thiab qhov cua txias yog tswj ntawm 5-8℃/ s, hloov lub microstructure ntawm txoj kev tsheb ciav hlau mus rau hauv zoo{12}}grained pearlite, tsis txhob ntxhib-cov qauv nplej thiab txhim kho qis{18}} kub toughness. Cov txheej txheem kub-kub qis ua kom sov lub tsheb ciav hlau mus rau 200-250 degree, ua kom sov li 2-3 teev, thiab tom qab ntawd cua-txias mus rau chav sov. Cov txheej txheem no tuaj yeem tshem tawm cov kev ntxhov siab uas tshwm sim thaum lub caij tsheb ciav hlau dov, thaum tswj kev ruaj ntseg ntawm pearlite qauv, zam kev txo lub zog los ntawm kev kub siab heev. Qhov cuam tshuam ntawm qhov kub-kho rail ntawm -40℃yog nce los ntawm ntau tshaj 50%, thiab lub zog yog khaws cia siab tshaj 1100MPa, ua tau raws li qhov yuav tsum tau siv ntawm cov cheeb tsam alpine.
Dab tsi yog qhov kev ua tau zoo sib txawv ntawm lub teb chaws tus qauv kev tsheb ciav hlau rau thaj tsam alpine thiab lub teb chaws tus qauv zoo tib yam?
Qhov kev ua tau zoo sib txawv ntawm lub teb chaws tus qauv tsheb ciav hlau rau thaj tsam alpine thiab lub teb chaws tus qauv kev tsheb ciav hlau feem ntau yog tshwm sim hauv peb yam:qis-kub tej yam toughness, tawg tiv thaiv kev pab them nqi thiab lub zog stability. Lub zog cuam tshuam ntawm lub teb chaws tus qauv kev tsheb ciav hlau rau thaj tsam alpine yog ntau dua lossis sib npaug ntawm 30J ntawm -40 degree, thaum lub teb chaws tus qauv qauv tsuas yog 20J ntawm -20℃thiab yuav poob qis dua 15J ntawm -40 degree, nws yuav ua rau tawg tawg. Nyob rau hauv cov nqe lus ntawm kev tawg tsis kam, qhov qaug zog tawg ntawm kev loj hlob ntawm lub teb chaws tus qauv kev tsheb ciav hlau rau thaj tsam alpine yog 30% -40% qis dua li ntawm cov qauv hauv teb chaws zoo tib yam, uas tuaj yeem cuam tshuam cov tiam thiab kev nthuav tawm ntawm cov kab nrib pleb hauv qhov chaw qis qis; qhov kev loj hlob ntawm qhov tawg ntawm lub teb chaws tus qauv zoo tib yam yog ceev ceev ntawm qhov kub thiab txias, nws yooj yim rau rail tawg. Nyob rau hauv cov nqe lus ntawm lub zog stability, qhov sib txawv ntawm tensile lub zog ntawm lub teb chaws tus qauv rails rau alpine cheeb tsam yog tsawg tshaj li los yog sib npaug li 5% nyob rau hauv qhov kub thiab txias ntawm -40℃-20 degree, thaum lub sij hawm ntawm lub teb chaws tus qauv zoo tib yam rails yuav ncav cuag 10%, thiab kub hloov yuav ua rau lub zog tsis ruaj khov. Tsis tas li ntawd, qhov sib txawv ntawm qhov sib txawv ntawm lub teb chaws tus qauv kev tsheb ciav hlau rau thaj tsam alpine yog qhov zoo dua, nrog rau qhov sib txawv ntawm qhov sib txawv tsawg dua los yog sib npaug rau HRC2, thaum lub teb chaws tus qauv zoo tib yam tuaj yeem ncav cuag HRC5.
Dab tsi yog qhov hloov kho kev ntsuas ntawm vuam txheej txheem rau lub teb chaws tus qauv rails nyob rau hauv alpine cheeb tsam?
Kev hloov kho kev ntsuas ntawm vuam txheej txheem rau lub teb chaws tus qauv rails nyob rau hauv alpine cheeb tsam yog tsuas yog raws li nyob rau hauvtxo vuam kub gradient thiab txhim kho tom qab-weld kub khokom tsis txhob qis -kub brittleness ntawm welded pob qij txha. Ua ntej welding, lub tsheb ciav hlau sib koom yuav tsum tau preheated rau 250-300 degree, nrog preheating ntau ntawm 100mm ntawm ob sab ntawm kev sib koom tes, 50{10}}100℃siab dua qhov kub ntawm preheating ntawm cov ntsia hlau zoo tib yam, txo qhov kub qhov sib txawv ntawm cov vuam thiab lub hauv paus hlau thiab txo cov welding residual stress. Vuam adopts flash pob tw vuam txheej txheem, nrog vuam tam sim no tswj ntawm 300-350A thiab vuam ceev tswj ntawm 100-150mm/min, txo qhov dav ntawm vuam tshav kub- cuam tshuam cheeb tsam, uas yog tswj ntawm 20- coaffected cheeb tsam nyob rau hauv 30mm. Kev kho cua sov tom qab siv cov txheej txheem kub qis, ua kom sov qhov sib koom ua ke rau 200-250℃thiab ua kom sov li 3-4 teev, tshem tawm cov vuam seem ntawm kev ntxhov siab thiab txhim kho qhov kub tsis tshua muaj kev cuam tshuam toughness ntawm kev sib koom tes. Tsis tas li ntawd, qhov sib koom ua ke yuav tsum tau kuaj xyuas qhov tsis zoo ntawm ultrasonic kom tsis txhob muaj qhov tsis xws luag, thiab qhov kev kuaj pom qhov tsis zoo yog siab dua li cov ntsia hlau zoo tib yam, tsis tas yuav muaj cov kab nrib pleb, qhov pores thiab lwm yam tsis xws luag hauv qhov vuam.
Dab tsi yog qhov ntawm - qhov chaw tso thiab tu cov ntsiab lus ntawm lub teb chaws tus qauv kev tsheb ciav hlau hauv thaj tsam alpine?
Qhov ntawm - qhov chaw tso thiab kev saib xyuas ntawm lub teb chaws tus qauv kev tsheb ciav hlau hauv cheeb tsam alpine yuav tsum tau tsom mus rauqhov kub thiab txias tso tawm thiab qis -kev tiv thaiv kub tawgkom muaj kev ruaj ntseg ntawm txoj kab. Kev tso tawm yuav tsum tau ua thaum qhov kub siab tshaj -10 degree, tsis txhob muaj qhov kub thiab txias ntawm txoj kev tsheb ciav hlau tshwm sim los ntawm kev tso ntawm qhov kub tsawg. Txoj kev tsheb ciav hlau dav dav rau kev tsheb ciav hlau nteg yog tswj ntawm 10-15mm, 5-10mm wider tshaj li nyob rau hauv cov cheeb tsam zoo tib yam, tshwj xeeb kub expansion qhov chaw los tiv thaiv txoj kev tsheb ciav hlau los ntawm kev tawg vim tensile stress generated los ntawm kub hloov. Tom qab tso, kev kho kev ntxhov siab yuav tsum tau ua, siv cov txheej txheem kev pab cuam rau cov menyuam kom sib npaug ntawm qhov kub thiab txias ntawm txoj kev tsheb ciav hlau, thiab qhov ntsuas kub ntawm lub tsheb ciav hlau kaw tom qab kev ntxhov siab yog tswj ntawm -5℃-5 degree. Thaum lub sij hawm txij nkawm, nws yog ib qho tsim nyog yuav tsum tsis tu ncua xyuas cov kab nrib pleb thiab hnav ntawm qhov chaw tsheb ciav hlau nrog kev tshuaj xyuas lub voj voog ntawm 3 lub hlis, 3 lub hlis luv dua li hauv cheeb tsam zoo tib yam. Txoj kev tsheb ciav hlau yuav tsum tau ua hauv av los yog hloov lub sijhawm thaum qhov tawg qhov ntev tshaj 5 hli. Tsis tas li ntawd, cov tshuaj tiv thaiv corrosion yuav tsum tau siv rau sab ntawm txoj kev tsheb ciav hlau los tiv thaiv kev xeb ntawm txoj kev tsheb ciav hlau los ntawm cov dej khov, daus thiab ntsev tsuag hauv thaj tsam alpine.