(1) Weldability ntawm hlau thiab txhuas thiab nws cov alloys
Hlau, manganese, chromium, npib tsib xee thiab lwm yam hauv cov hlau tuaj yeem sib xyaw nrog txhuas hauv cov kua hauv lub xeev kom tsim cov tshuaj tsis muaj zog, thiab tseem tsim cov tshuaj sib xyaw ua ke. Cov pa roj carbon hauv cov hlau kuj tuaj yeem tsim cov tebchaw nrog txhuas, tab sis lawv yuav luag tsis sib haum nrog ib leeg hauv lub xeev. yaj. Nyob nruab nrab ntawm cov ntsiab lus sib txawv ntawm txhuas thiab hlau, ntau yam nkig intermetallic tebchaw tuaj yeem tsim, ntawm cov FeAls yog cov nkig tshaj plaws.
Nws muaj qhov cuam tshuam loj rau cov khoom siv ntawm cov welded pob qij txha ntawm cov hlau thiab txhuas, nrog rau microhardness. Tsis tas li ntawd, txij li cov khoom siv thermophysical ntawm cov hlau, txhuas thiab lawv cov alloys kuj sib txawv heev, cov weldability ntawm steel thiab aluminium yog deteriorated.
(2) Vuam txheej txheem ntawm hlau thiab txhuas thiab nws cov alloys
Los ntawm cov kev soj ntsuam saum toj no ntawm steel-aluminium weldability, nws yuav luag tsis tuaj yeem txo qis ntawm cov hlau thiab txhuas thiab nws cov alloys los ntawm kev sib txuas ncaj qha welding.
Nws yuav luag tsis yooj yim sua kom siv cov hlau lossis hlau uas nws lub cev muaj zog thermal yog nruab nrab ntawm cov hlau thiab txhuas thiab uas tuaj yeem ua tau metallurgically sib xws nrog ob qho tib si ua cov hlau muab tub lim rau kev vuam ncaj qha.
Nyob rau hauv kev xyaum ntau lawm, muaj ob txoj kev: txheej txheej indirect fusion vuam thiab intermediate hloov daim indirect fusion vuam.
1) Txheej txheej indirect welding txoj kev Ua ntej steel thiab txhuas yog welded, ib los yog ob peb txheej ntawm hlau uas yuav metallurgically fused nrog ib tug tsim nyog muab tub lim hlau yog pre-coated rau saum npoo ntawm cov hlau los tsim ib tug pre-txheej txheej, thiab ces. siv Gas tungsten arc vuam txoj kev Ib txoj kev ntawm vuam coated steel rau txhuas.
Ua pov thawj los ntawm kev xyaum thiab kev xeem:
Ib txheej txheej txheej tsuas tuaj yeem tiv thaiv oxidation ntawm lub hauv paus hlau, tab sis tsis tuaj yeem tiv thaiv lub cim ntawm intermetallic compounds, thiab nws lub zog sib koom ua ke tseem tsawg heev. Yog li ntawd, argon arc vuam ntawm cov hlau thiab txhuas yuav tsum tau nqa tawm nrog cov txheej txheem sib xyaw.
Muaj ntau cov ntaub ntawv hlau rau txheej, xws li Ni, Cu, Ag, Sn, Zn thiab lwm yam. Cov khoom siv hlau txheej yog txawv, thiab qhov tshwm sim tom qab vuam kuj txawv. Cov kab nrib pleb yog yooj yim tsim rau Ni, Cu, Ag txheej txheej; Ni, Cu, Sn composite txheej yog zoo dua; Ni, Zn composite txheej muaj cov nyhuv zoo tshaj plaws.
Lub argon arc vuam ntawm cov sib xyaw coated carbon steel thiab txhuas thiab nws cov alloys yog thawj txheej txheej ntawm cov hlau xws li tooj liab lossis nyiaj ntawm cov hlau sab, thiab tom qab ntawd txheej txheej zinc. Thaum welding, zinc melts ua ntej (vim lub melting point ntawm vuam hlau yog siab tshaj li zinc), thiab ntab rau ntawm cov kua nto.
Aluminium reacts nrog tooj liab los yog nyiaj plating nyob rau hauv lub zinc txheej, thiab nyob rau tib lub sij hawm cov tooj liab thiab los yog nyiaj dissolves nyob rau hauv lub txhuas, uas yuav tsim ib tug zoo welded sib koom. Nws tuaj yeem ua kom lub zog ntawm steel-aluminium welded pob qij txha rau 197 ~ 213MPa.
Tom qab cov khoom siv hlau yog coated, qhov saum npoo ntawm cov hlau thiab txhuas tuaj yeem kho tau. Kev kho saum npoo ntawm txhuas qhov chaw yog eroded nrog 15% ~ 20% NaOH los yog KOH tov kom tshem tawm cov oxide zaj duab xis, rinsed nrog dej huv, ces passivated nyob rau hauv 20% HNO3, yaug, thiab npaj kom qhuav ua argon arc vuam.
Vuam cov ntaub ntawv - xaiv cov ntshiab aluminium welding hlau nrog cov ntsiab lus silicon tsawg, kom cov pob qij txha zoo tuaj yeem tau txais. Nws tsis tsim nyog siv magnesium-muaj welding hlau (LFS), vim tias nws yuav txhawb kev loj hlob ntawm intermetallic tebchaw thiab tsis tuaj yeem lav lub zog ntawm kev sib koom ua ke.
Vuam txoj kev - tus txheeb ze txoj hauj lwm ntawm workpiece, vuam hlau thiab tungsten electrode thaum vuam.
Txhawm rau tiv thaiv kev kub hnyiab ntxov ntawm cov hlau txheej txheej, thaum vuam thawj zaug, vuam arc yuav tsum tau khaws cia rau ntawm cov hlau muab tub lim; Rau cov welds tom ntej, lub arc yuav tsum tau khaws cia rau ntawm cov xaim xaim thiab cov hlau tsim, kom nws tuaj yeem zam lub arc ncaj qha rau ntawm txheej.
Tsis tas li ntawd, lub arc txav mus rau saum npoo ntawm txhuas sab thiab aluminium vuam hlau txav raws li cov hlau sab, kom cov kua txhuas ntws mus rau qhov zawj ntawm cov hlau sib xyaw, thiab cov txheej tsis tuaj yeem hlawv ua ntej thiab poob. nws cov nyhuv.
Vuam specification - argon arc vuam ntawm cov hlau thiab txhuas siv AC lub zog, ib qho yog ntaus cov oxide zaj duab xis thiab tawg nws, thiab nws tseem tuaj yeem tshem tawm cov oxide zaj duab xis rau saum npoo ntawm lub pas dej molten, kom cov hlau molten weld tuaj yeem ua tau. zoo fused.
Lub vuam tam sim no raug xaiv raws li qhov tuab ntawm qhov vuam. Feem ntau, thaum lub phaj thickness yog 3 hli, qhov vuam tam sim no yog 110-130A; Thaum lub phaj thickness yog 6-8 hli, vuam tam sim no yog 130-160A;
2) Indirect fusion vuam txoj kev rau nruab nrab hloov daim. Txoj kev vuam no yog muab lub prefabricated steel-aluminium composite vaj huam sib luag nyob rau hauv nruab nrab ntawm lub steel-aluminium sib koom ua lawv tus kheej cov pob qij txha, uas yog, steel-steel thiab aluminium-aluminium pob qij txha. Tom qab ntawd siv cov txheej txheem fusion welding cov txheej txheem los txuas cov hlau tib yam ntawm ob qho kawg.
Thaum vuam, xyuam xim rau vuam aluminium pob qij txha nrog loj shrinkage thiab yooj yim thermal tawg ua ntej, thiab ces welding steel pob qij txha.
Post lub sij hawm: Mar-22-2023
