Ua rau Dub Streak Defects hauv Cov Txheej Txheem Rolling Ntawm TC4 Titanium Bars

TC4 (Ti-6Al-4V) yog martensitic a+/3 ob-theem titanium alloy nrog kev ua haujlwm zoo, thiab nws qhov kev pabcuam kub tuaj yeem ncav cuag 450, uas yog dav siv hauv cov qauv tseem ceeb ntawm cov khoom siv. aviation kev lag luam, xws li tis hniav thiab aero-engine disks. Txij li thaum TC4 titanium bar yog ob-theem titanium alloy, yog tias cov micro-zone muaj pes tsawg leeg tsis zoo ib yam, nws yuav ua rau muaj kev txawv txav hauv macro-organization thiab micro-organization, uas yuav ua rau muaj qhov sib txawv tseem ceeb hauv qhov nyuaj ntawm qhov txawv txav. cheeb tsam thiab cheeb tsam ib txwm, kom cov khoom siv nyob rau hauv tag nrho cov kev ua tau zoo ntawm qhov kev ua tau zoo ntawm qhov tsis sib xws, thiab thaum kawg sprouting qaug zog tawg qhov chaw, ua rau muaj peev xwm txaus ntshai rau kev nyab xeeb ntawm cov khoom siv, thiab txo cov kev pab cuam lub neej ntawm cov hlau. . Txhawm rau txiav txim siab yam tsis xws luag hauv cov teeb meem dub streak pom nyob rau hauv TC4 titanium alloy bar cov khoom thaum lub sij hawm tsis tshua muaj magnification, ib lub tshuab ntsuas metallurgical tau siv los soj ntsuam cov microstructure thiab txiav txim siab qhov txawv txav ntawm lub koom haum metallurgical; Lub tshuab ntsuas hluav taws xob ntsuas hluav taws xob (SEM) tau siv los txheeb xyuas thaj chaw dub streak raws li molybdenum-nplua nuj thiab txhuas-tsis muaj tshuaj los nag lossis dej tsis zoo; thiab ib qho kev sim micro-hardness tau ua los txiav txim siab tias cov nag lossis daus nyob hauv cov cheeb tsam dub yog cov nag lossis daus. Cov txiaj ntsig kev sim qhia tau hais tias, raws li cov txheej txheem saum toj no tuaj yeem txiav txim siab zoo TC4 titanium alloy kev sib cais sib cais thiab nws hom; thiab txiav txim siab tias hom kev tsis zoo no tsis cuam tshuam rau kev siv qhov kev txiav txim tuaj yeem xa tuaj. Cov teeb meem zoo li no tuaj yeem raug txo lossis tshem tawm los ntawm kev tswj hwm kev xaiv cov khoom siv raw rau titanium alloy ingots, kev sib xyaw thiab cov txheej txheem electrode, thiab qhov voltage thiab tam sim no hauv cov txheej txheem melting. Titanium alloy segregation, raws li qhov chaw sib cais thiab thaj chaw ib txwm muaj qhov nyuaj ntawm qhov sib txawv ntawm qhov siab thiab qis qis, tuaj yeem muab faib ua ib qho nyuaj segregation (hardness siab dua li thaj chaw ib txwm muaj, tseem hu ua brittle segregation) thiab mos sib cais (hardness yog qis dua qhov chaw ib txwm muaj, tseem hu ua kev sib cais tsis sib haum) ob pawg. Yog tias tsuas yog tsis muaj kev sib cais ntawm cov khoom lag luam, thiab qhov kev ua tau zoo raws li qhov yuav tsum tau ua ntawm cov qauv khoom, qhov kev txiav txim siab dav dav ntawm kev sib cais ntawm cov khoom tseem tuaj yeem xa tuaj rau kev siv; Kev sib cais tsis pub muab tshem tawm los ntawm kev xa khoom, tag nrho cov khoom yuav tsum tau muab pov tseg. Tus neeg sau tham txog kev tshuaj xyuas thiab kev txiav txim siab ntawm kev sib cais tsis sib haum xeeb tau ntsib hauv TC4 titanium alloy bar segregation, aiming muab kev siv rau kev tshuaj xyuas cov khoom los txhim kho cov khoom zoo.

a. Ntawm qhov pom kev pom ntawm TC4 titanium bar dub streak defects, kev siv metallurgical microscopy los soj ntsuam nws cov microstructure, qhov chaw tsis zoo tsis txawv ntau ntawm thaj chaw ib txwm muaj, tsis tuaj yeem txiav txim siab yam tsis xws luag; ntxiv scanning electron microscopy ntawm qhov chaw tsis raug ntawm titanium bar tshuaj lom neeg muaj pes tsawg leeg tsom xam, qhov chaw tsis zoo rau cov ntsiab lus ntawm aluminium-nplua nuj vantage ntawm cov tshuaj lom neeg ntawm kev sib cais; thiab thaum kawg ua ke nrog kev ntsuas micro-hardness los txiav txim seb hom kev sib cais ntawm TC4 titanium bar aluminium-nplua nuj tsis nkig segregation; brittle kev sib cais; thiab thaum kawg ua ke nrog kev sim micro-hardness los txiav txim seb hom kev sib cais tau ntsib hauv TC4 titanium bar segregation. Kev sib cais; los ntawm kev soj ntsuam microstructure, micro-chaw muaj pes tsawg leeg tsom xam thiab microhardness xeem ua ke txoj kev, tuaj yeem txiav txim siab zoo TC4 titanium alloy muaj pes tsawg leeg sib cais thiab nws hom.
b. Kev sib cais nyob rau hauv TC4 titanium alloy bar yog ib qho kev sib cais ntawm cov khoom siv txhuas-nplua nuj thiab txhuas-tsis zoo, uas tsis cuam tshuam rau kev siv, thiab tuaj yeem xa tuaj tom qab txiav; xws li tsis xws luag yuav raug txo los yog tshem tawm los ntawm kev tswj cov kev xaiv ntawm raw cov ntaub ntawv, mixing thiab electrode npaj tsis, thiab voltage thiab tam sim no nyob rau hauv lub melting txheej txheem.