1. Vuam nrog carbon hlau (piv txwv li, Q235, A36)
Ua tau: Muaj peev xwm ua tau zoo- carbon steel muaj lub zog qis thiab zoo weldability, sib xws nrog 09CuPCrNi-A's qis- alloy muaj pes tsawg leeg.
Yam Tseem Ceeb: Galvanic corrosion ntawm qhov sib koom ua ke (09CuPCrNi-A muaj kev tiv thaiv corrosion ntau dua li carbon steel; carbon steel yuav corrode nyiam nyob rau hauv qhov chaw ntub dej).
Cov kev ceev faj:
Filler Hlau Xaiv: Sivhuab cua-qib qis- hydrogen electrodes/wires(piv txwv li, E7016-G, ER50-6NiCu) es tsis txhob carbon steel muab tub lim. Qhov no ua kom cov hlau vuam muaj Cu / Cr / Ni alloying cov ntsiab lus kom phim 09CuPCrNi-A qhov kev tiv thaiv corrosion, txo galvanic corrosion.
Ncej -Kev kho Weld: Siv ib lub passivator lossis patina accelerator rau tag nrho cheeb tsam sib koom ua ke los txhawb cov txheej txheej xeb tsis sib xws. Rau kev siv sab nraum zoov, pleev xim rau sab carbon steel nrog tiv thaiv - xim xim kom cais tawm ntawm qhov chaw corrosive.
Thaum tshav kub kub input Control: Khaws cov khoom cua kub tsawg dua lossis sib npaug li 25 kJ / cm2 kom tsis txhob muaj cov pa roj carbon steel HAZ ntau dhau (kub- thaj tsam cuam tshuam).
2. Vuam nrog High-Lub zog qis-Alloy Steel (piv txwv li, Q355, A572 Gr 50)
Ua tau: Kev ua tau zoo- lawv lub zog thiab tshuaj lom neeg muaj pes tsawg leeg nyob ze rau 09CuPCrNi-A, txo qis cov cuab yeej cuab tam tsis sib haum.
Yam Tseem Ceeb: Txias tawg (siab- steel muaj zog dua hardenability; ceev txias tom qab vuam yuav ua rau martensite tsim nyob rau hauv HAZ).
Cov kev ceev faj:
Filler Hlau Xaiv: Siv cov fillers sib piv rau qhov siab dua - lub zog sab (piv txwv li, ER50-6NiCu rau Q355, E7018 rau A572 Gr 50) kom ntseeg tau tias lub zog tensile ntau dua lossis sib npaug rau qis dua - lub zog lub hauv paus hlau (09CuPCrNi-A).
Preheating & Interpass kub: Preheat to 80–150°C for plates >16 hli; tuav interpass kub tsawg dua los yog sib npaug li 200℃kom txo tau qhov txias txias thiab tsis txhob txias cracking.
Tshaj tawm - Weld Stress Relief: For thick plates (>20mm) los yog siab -cov qauv kev ntxhov siab, ua PWHT (550–620 degree) kom txo tau qhov kev ntxhov siab.
3. Vuam nrog Stainless hlau (xws li, 304, 316)
Ua tau: Ua tau tab sistsis pom zoo rau sab nraum zoov / corrosive ib puag ncig-Qhov sib txawv loj hauv electrochemical muaj peev xwm thiab thermal expansion coefficients ua rau hnyav galvanic corrosion thiab vuam deformation.
Yam Tseem Ceeb:
Galvanic corrosion: Stainless hlau yog corrosion ntau dua -resistant dua 09CuPCrNi-A; 09CuPCrNi-A yuav corrode sai ntawm qhov sib koom ua ke.
Thermal tawg: Stainless hlau muaj ntau dua thermal expansion; vuam shrinkage yuav ua rau tawg nyob rau hauv lub 09CuPCrNi-A HAZ.
Kev ceev faj (yog tias tsis tuaj yeem zam tau):
Filler Hlau Xaiv: Sivaustenitic stainless hlau fillers nrog cov ntsiab lus siab nickel(piv txwv li, ER309L) los tsim ib txheej tsis nyob nruab nrab ntawm ob lub hlau, txo galvanic corrosion.
Tus Qauv Tsim: Siv akev hloov pauv kev sib koom ua ke(xws li, 309L clad phaj) es tsis txhob welding ncaj qha rau cais ob hlau.
Tshaj tawm - Weld Isolation: Siv cov txheej tuab ntawm insulating txheej los yog sealant rau qhov sib koom ua ke los tiv thaiv electrolyte (moisture, ntsev tsuag) los ntawm kev sib cuag ob qho tib si hlau ib txhij.
4. General Vuam Principles for Dissimilar Steels
Ua ntej Corrosion Resistance Matching: Ib txwm xaiv cov hlau muab tub lim uas ua tau raws li qhov yuav tsum tau ua kom muaj kev tiv thaiv corrosion ntau dua (feem ntau yog cov huab cua sab hauv steel) kom tsis txhob muaj kev nyiam corrosion.
Tsis txhob vuam nrog cov hlau tsis yog- ferrous: Kev vuam ncaj qha nrog txhuas, tooj liab, thiab lwm yam, tsis tuaj yeem ua tau vim qhov sib txawv loj hauv cov ntsiab lus melting thiab thermal conductivity; siv cov khoom sib txuas (piv txwv li, bolts) hloov.
NDT Inspection: Ua 100% VT (kev kuaj pom) thiab UT / RT (ultrasonic / radiographic kuaj) ntawm cov pob qij txha sib txawv kom pom cov kab nrib pleb, porosity, lossis tsis tiav fusion.
