Titanium thiab titanium- clad steel daim hlau yog nyiam nyob rau hauv xav tau sectors xws li aerospace thiab kev kho mob technology rau lawv tshwj xeeb lub zog - mus rau - luj piv thiab superior corrosion kuj. Txawm li cas los xij, kev ua tiav flawless welds feem ntau cuam tshuam los ntawm kev sib tw tseem ceeb: tawg. Qhov teeb meem tsis tu ncua no cuam tshuam cov qauv kev ncaj ncees thiab ua rau muaj kev cuam tshuam loj rau kev tsim kev ntseeg siab. Qhov tob tob rau hauv cov hauv paus hniav metallurgical ua rau pom tias hydrogen embrittlement yog thawj antagonist, nrog rau nws cov teebmeem loj los ntawm kev ntxhov siab thiab tsis muaj kev tswj xyuas thermal.
Lub hauv paus txheej txheem tom qab weld cracking yog hydrogen -induced txias cracking. Hydrogen, tsim los ntawm cov khoom paug xws li ya raws, roj, lossis huab cua av noo, yaj mus rau hauv lub pas dej molten weld thaum lub sij hawm siab -kub arc theem. Raws li cov hlaws weld solidifies thiab txias, hydrogen solubility plummets. Tshaj hydrogen, daig los ntawm cov cua txias ceev, ua supersaturated nyob rau hauv weld hlau microstructure. Qhov no entrapped hydrogen ces tsiv mus nyob rau thaj tsam ntawm high tri-axial stress, hnyav embrittling cov hlau thiab drastic txo nws ductility, yog li pib micro-fissures.
Cov txheej txheem embrittlement no tau nrawm nrawm los ntawm kev sib koom ua ke ntawm kev ntxhov siab concentrators thiab hauv zos hydrogen tsub zuj zuj. Notches, xws li cov los ntawm cov ntse undercuts los yog tsis tiav fusion, tsim cov kev ntxhov siab hauv zos. Thaum supersaturated hydrogen diffuses mus rau qhov siab - cov cheeb tsam kev ntxhov siab, nws txo qis qhov kev ntxhov siab tseem ceeb uas yuav tsum tau ua rau kev tawg tawm. Kev sib xyaw ua ke ntawm microstructure brittle thiab concentrated tensile stress tsim ib qho chaw zoo meej rau kev tawg thiab kev loj hlob.
Ib puag ncig tej yam kev mob, tshwj xeeb tshaj yog thaum lub caij txias, exacerbate cov kev pheej hmoo. Qhov ntsuas kub qis dua txhawb cov dej noo condensation ntawm cov khoom siv, qhia txog qib siab ntawm hydrogen. Tsis tas li ntawd, lub siab thermal diffusivity ntawm cov ntaub ntawv zoo li nyias - ntsuas titanium ua rau cov cua kub sai heev. Qhov no ceev ceev txias npaum li cas thaum vuam hnyav curtails lub qhov rais muaj rau hydrogen kom effuse los ntawm solidifying weld, yuam nws tuav nyob rau hauv ib tug supersaturated lub xeev thiab siab cracking susceptibility.
Lub tswv yim kev txo qis kom muaj zog xav tau ib txoj hauv kev uas tsom mus rau kev tswj hwm hydrogen thiab thermal tswj. Thawj kab ntawm kev tiv thaiv yog immaculate nto npaj. Ob lub hauv paus hlau thiab muab tub lim hlau yuav tsum tau ua tib zoo kho txhua yam thiab tshuaj ntxuav kom tshem tawm tag nrho cov kab mob hydrocarbon thiab hydroxide, yog li kaw thawj qhov chaw hydrogen ntawm nws keeb kwm.
Ib puag ncig thiab thermal tswj ua tus ncej tseem ceeb thib ob. Kev tuav tswj qhov chaw vuam yog qhov tseem ceeb los tiv thaiv atmospheric noo noo kom tsawg. Rau titanium-clad steel, preheating lub substrate steel interface ua hauj lwm ob lub hom phiaj: nws zoo tsav tawm adsorbed ya raws thiab, qhov tseem ceeb tshaj, txo qhov vuam tus nqi txias. Lub voj voog qeeb qeeb no tso cai rau cov dej hydrogen txaus rau lub sij hawm kom diffuse tawm ntawm qhov vuam ua ntej nws yuav raug daig, ua kom muaj peev xwm ua kom muaj zog.
Thaum kawg, cov txheej txheem welding zoo tshaj plaws yog qhov tseem ceeb. Precise calibration ntawm tshav kub input los ntawm tsis xws li tam sim no, voltage, thiab mus txawv tebchaws ceev ncaj qha tswj lub weld lub thermal profile. Lub hom phiaj yog los tsim kom muaj kev tswj hwm, qis qis qis qis uas ua rau muaj kev cuam tshuam hydrogen egress yam tsis muaj kev cuam tshuam rau cov qauv metallurgical lossis txhawb kev loj hlob ntau dhau. Hauv kev xaus, kev tiv thaiv titanium vuam cov kab nrib pleb tsis yog ib qho kev daws teeb meem nkaus xwb tab sis ib qho kev sib koom ua ke ntawm kev cuam tshuam cov khoom siv hydrogen, tswj cov thermal dynamics, thiab cov txheej txheem vuam zoo los xyuas kom muaj kev sib koom ua ke thiab kev ua haujlwm ntev -.
