Muaj ntau cov ntsiab lus hauv titanium alloys, uas muaj kev cuam tshuam rau lub cev ntawm titanium. Cov pa roj carbon monoxide yog ib qho impurity hauv titanium thiab titanium alloys. Thaum cov ntsiab lus carbon tsawg dua 0.13%, cov pa roj carbon yog sib sib zog nqus hauv titanium, thiab lub zog vuam yog txwv. Muaj qee qhov kev txhim kho thiab qee qhov txo qis hauv plasticity, tab sis tsis muaj zog npaum li cov nyhuv ntawm oxygen thiab nitrogen. Txawm li cas los xij, thaum cov ntsiab lus carbon ntawm cov vuam txuas ntxiv, lub network TiC tshwm hauv qhov vuam, thiab tus lej nce nrog cov ntsiab lus ntawm cov pa roj carbon ntau, ua rau cov yas ntawm cov vuam poob qis, thiab cov kab nrib pleb yog qhov tshwm sim hauv qhov kev txiav txim. ntawm welding kev nyuaj siab.
1. Kev cuam tshuam ntawm cov ntsiab lus carbon
Titanium thiab titanium alloys kuj ruaj khov thaum lub sij hawm vuam txheej txheem ntawm chav tsev kub. Cov kua dej thiab cov pas dej molten hlau muaj peev xwm nqus tau hydrogen, oxygen, thiab nitrogen, thiab nyob rau hauv cov khoom muaj zog, cov roj no tau cuam tshuam nrog lawv. Raws li qhov kub thiab txias, lub peev xwm ntawm titanium thiab titanium alloys nqus hydrogen, oxygen, thiab nitrogen kuj nce ntxiv. Titanium pib nqus hydrogen ntawm 250 degree, oxygen ntawm 400 degree, thiab nitrogen ntawm 600 degree. Tom qab cov roj tau absorbed, nws yuav ncaj qha ua rau lub vuam sib txuas mus rau embrittle, uas yog ib qho tseem ceeb heev cuam tshuam rau lub vuam zoo.
2. Kev cuam tshuam ntawm hydrogen
Qhov laj thawj tseem ceeb yog tias cov ntsiab lus ntawm cov foob pob hydrogen nce nrog cov seam. Hydrogen yog qhov tseem ceeb tshaj plaws uas muaj feem cuam tshuam loj tshaj plaws ntawm cov khoom siv ntawm titanium ntawm cov pa impurities. Kev hloov pauv hauv cov ntsiab lus hydrogen ntawm cov weld muaj qhov cuam tshuam loj tshaj plaws ntawm cov khoom siv ntawm cov vuam. Lub flake los yog koob zoo li TiH2 precipitated nyob rau hauv lub weld nce. Lub zog ntawm TiH2 yog qhov tsawg heev, yog li cov nyhuv ntawm flaky lossis koob zoo li HiH2 yog tias cov khoom cuam tshuam tau txo qis; qhov kev hloov pauv hauv cov ntsiab lus hydrogen ntawm cov vuam tsis tshua muaj kev cuam tshuam rau kev txhim kho lub zog thiab txo qis ntawm plasticity.
3. Cov nyhuv ntawm cov pa oxygen
Lub hardness thiab tensile lub zog ntawm weld nce ntau, thiab cov pa oxygen ntawm cov weld pib nce linearly nrog qhov nce ntawm cov pa oxygen ntawm cov roj argon. Lub plasticity yog txo qis. Txhawm rau kom ntseeg tau tias qhov kev ua tau zoo ntawm cov pob qij txha welded, oxidation ntawm vuam seam thiab vuam qhov chaw kub-tshem yuav tsum tau nruj me ntsis tiv thaiv thaum lub vuam txheej txheem.
4. Cov nyhuv ntawm nitrogen
Nitrogen reacts hnyav nrog titanium daim hlau ntawm qhov kub siab tshaj 700 degree . Kev tsim cov nkig thiab tawv titanium nitride (TiN) thiab cov degree ntawm lattice distortion tshwm sim los ntawm kev tsim ntawm interstitial khoom tov ntawm nitrogen thiab titanium yog hnyav dua li qhov tshwm sim los ntawm tib tus nqi ntawm cov pa. Yog li ntawd, nitrogen tuaj yeem txhim kho qhov ua haujlwm ntawm kev lag luam ntshiab titanium welds. Lub zog tensile, hardness, thiab cov khoom yas ntawm cov vuam yog txo qis dua li cov pa oxygen. Thaum cov ntsiab lus nitrogen ntawm cov weld yog siab dua 0.13%, lub vuam yuav tawg vim yog cov brittleness ntau dhau.
