Titanium alloy forging tsis xws luag thiab lawv tiv thaiv

Thaum titanium alloy forging, vim cov txheej txheem tsis tsim nyog, cov khoom siv raw khoom zoo tswj tsis nruj thiab lwm yam laj thawj, forging yuav muaj ntau yam tsis xws luag. Cov tsis xws luag yog raws li nram no:
1, b rhiab
β embrittlement yog tshwm sim los ntawm overheating ntawm forging. α thiab (α + β) titanium alloys, tshwj xeeb tshaj yog (α + β) titanium alloys, yog hais tias lub forging cua sov kub yog siab dhau lawm, tshaj nws β hloov kub, ua rau lub forging ntawm tsawg lub sij hawm lub koom haum ntawm cov nplej yog loj, isometric. ; microstructure ntawm α-theem nag lossis daus raws li cov ciam teb ntawm cov ntxhib qub β cov nplej thiab cov intracrystalline yog striated. Qhov tshwm sim yog tias cov yas ntawm forging ntawm chav tsev kub yog txo, qhov tshwm sim no hu ua β embrittlement.
Lub overheating tsis xws luag ntawm titanium alloy forgings tsis tuaj yeem kho los ntawm kev kho cua sov, tab sis yuav tsum tau kho los ntawm reheating kom qis dua β-hloov kub (yog tias forging tso cai) rau cov yas deformation.
Txhawm rau tiv thaiv overheating los ntawm qhov tshwm sim, titanium alloy cua sov, lub qhov cub kub yuav tsum tau tswj nruj me ntsis, kev txiav txim siab tsis tu ncua ntawm qhov ntsuas kub ntawm qhov tsim nyog ntawm lub cub tawg chamber, qhov tsim nyog ntawm qhov chaw them nqi thiab tus nqi them tsis tuaj yeem. feem ntau. Thaum siv cov cua sov ua kom sov, lub cub tawg yuav tsum tau teem rau ntawm ob sab ntawm lub baffle, thiaj li tsis txhob overheating los ntawm cov billet ze ze ntawm silicon carbide pas nrig. Tshawb xyuas qhov tseeb β-kev hloov pauv kub ntawm txhua qhov cub tawg kuj yog ib qho kev ntsuas zoo los tiv thaiv overheating.

2, localized coarse siv lead ua
Nyob rau hauv lub rauj los yog xovxwm tuag forging, vim tsis zoo thermal conductivity ntawm titanium alloys, billet nto thiab pwm kev sib cuag txheej txheem kub yog txo ntau, ua ke nrog rau saum npoo ntawm lub billet thiab pwm kev sib txhuam ntawm lub sab sauv thiab sab pwm, lub billet nruab nrab. ib feem ntawm lub billet yog raug rau muaj zog deformation, nto ntawm deformation ntawm lub degree ntawm me me, thiaj li hais tias cov raw khoom ntawm lub koom haum yog khaws cia, tsim ib tug tshiab localized ntxhib. siv lead ua.
Txhawm rau kom tsis txhob titanium alloy hauv zos ntxhib siv lead ua tsis xws luag, cov kev ntsuas hauv qab no tuaj yeem ua: siv cov txheej txheem ua ntej forging, kom qhov kawg forging deformation uniformity; ntxiv dag zog rau lub lubrication, txhim kho kev sib txhuam ntawm cov billet thiab pwm; tag nrho preheat lub pwm kom txo tau cov billet nyob rau hauv cov txheej txheem forging ntawm qhov kub thiab txias.
3, Crack
Titanium alloy forging nto tawg yog tsuas yog tsim thaum qhov kawg forging kub yog qis dua tag nrho recrystallization kub ntawm titanium alloy. Nyob rau hauv cov txheej txheem tuag forging, lub sij hawm sib cuag ntawm lub billet thiab pwm yog ntev dhau lawm, vim qhov tsis zoo thermal conductivity ntawm titanium alloy, nws yooj yim los ua rau saum npoo ntawm lub billet txias hauv qab qhov kev tso cai zaum kawg forging kub, uas yuav ua rau tawg tawg. hauv forging. Yuav kom tswj tau qhov tshwm sim ntawm cov kab nrib pleb, thaum tuag forging ntawm cov xovxwm, iav lubricant yuav siv tau, los yog thaum forging rau rauj, sim ua kom luv lub sij hawm sib cuag ntawm qhov khoob thiab qis qis.
4, residual casting koom haum
Forging ntawm titanium alloy ingots, yog tias qhov sib piv forging tsis loj txaus lossis tsis tsim nyog forging txoj kev, forgings yuav raug tso tseg hauv lub koom haum casting. Txoj kev daws teeb meem no yog txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhawm rau txhaws).
5, Bright strip
Lub thiaj li hu ua titanium alloy forgings nyob rau hauv lub ci sawb, yog tam sim no nyob rau hauv lub qis-fold lub koom haum ntawm ib tug strip nrog ib tug txawv brightness pom rau qhov liab qab qhov muag band. Vim qhov sib txawv ntawm lub kaum sab xis ntawm lub teeb pom kev zoo, lub teeb ci ci tuaj yeem ci dua li lub hauv paus hlau, kuj tuaj yeem tsaus dua li lub hauv paus hlau. Hauv ntu ntu, nws yog nyob rau hauv daim ntawv ntawm cov dots lossis flakes; nyob rau hauv longitudinal seem, nws yog ib tug ntev du strip nrog ib tug ntev ntawm ntau tshaj kaum millimeters mus rau ob peb meters. Muaj ob lub ntsiab yog vim li cas rau lub ci tuav: ib qho yog cov tshuaj muaj pes tsawg leeg ntawm titanium alloy segregation, thiab qhov thib ob yog deformation ntawm cov txheej txheem forging thermal teebmeem.
Cov kab ci ci muaj qee yam cuam tshuam rau kev ua haujlwm ntawm titanium alloy, tshwj xeeb tshaj yog nyob rau hauv plasticity thiab kub ua haujlwm. Kev ntsuas los tiv thaiv qhov tshwm sim ntawm cov kab ci ntsa iab yog txhawm rau tswj xyuas cov smelting ntawm cov tshuaj muaj pes tsawg leeg ntawm kev sib cais; kev xaiv kom raug ntawm forging thermal specifications (cua sov kub, degree ntawm deformation, deformation ceev, thiab lwm yam), thiaj li yuav zam qhov kub ntawm forging pieces nyob txhua qhov chaw vim deformation ntawm thermal nyhuv ntawm qhov sib txawv yog loj heev.
6, α embrittlement txheej
α embrittlement txheej feem ntau yog titanium alloy ntawm qhov kub siab oxygen thiab nitrogen los ntawm cov tawv nqaij xoob oxide, mus rau sab hauv diffusion ntawm cov hlau, kom cov pa oxygen thiab nitrogen cov ntsiab lus ntawm cov hlau saum npoo nce, yog li nce tus naj npawb ntawm α-theem hauv lub lub koom haum nto. Thaum cov pa oxygen thiab nitrogen cov ntsiab lus ntawm cov hlau saum npoo mus txog ib qho nqi, lub koom haum saum npoo yuav ua tiav ntawm α theem. Nyob rau hauv txoj kev no, nto ntawm titanium alloy tsim ib txheej txheej nrog ntau dua α lossis tag nrho α theem. Cov txheej txheej saum npoo no muaj li ntawm α theem feem ntau hu ua α embrittlement txheej. Ib txheej tuab tuab heev ntawm α embrittlement nyob rau saum npoo ntawm titanium alloy billet tuaj yeem ua rau tawg ntawm lub pob zeb thaum lub sij hawm forging.
Lub thickness ntawm α embrittlement txheej yog ze ze rau hom cua sov rauv siv rau forging los yog kev kho cua sov, qhov xwm ntawm cov roj nyob rau hauv lub cub tawg, lub cua kub ntawm lub billet los yog ib feem, thiab lub sij hawm tuav. Nrog rau qhov nce hauv cua sov, tuav lub sij hawm nce lub thickness; nrog rau kev nce hauv cov pa oxygen thiab nitrogen cov ntsiab lus hauv cov pa roj thiab thickening. Yog li ntawd, txhawm rau kom tsis txhob muaj txheej txheej embrittlement yog tuab heev, forging lossis kev kho cua sov ntawm cov cua sov, tuav lub sij hawm thiab qhov xwm txheej ntawm lub cub tawg, thiab lwm yam, yuav tsum tau tswj kom zoo.
α, β thiab (α + β) titanium alloys yuav tsim α embrittlement txheej. Txawm li cas los xij, α titanium alloys tshwj xeeb tshaj yog rau kev tsim ntawm α embrittlement txheej, thaum β titanium alloys yuav tsis tsim α embrittlement txheej kom txog thaum lawv tau rhuab mus rau saum 980 ° C.

7, Hydrogen embrittlement
Muaj ob hom hydrogen embrittlement: strain time type thiab hydride type. Hydrogen atoms nyob rau hauv lub lattice qhov sib txawv nyob rau hauv kev nyuaj siab, tom qab ib tug tej lub sij hawm ntawm lub sij hawm diffusion sib sau ua ke mus rau qhov kev nyuaj siab concentration ntawm qhov sib txawv. Vim yog kev sib cuam tshuam ntawm hydrogen atoms thiab dislocations kom cov dislocations pinned, tsis tuaj yeem txav mus los ywj pheej, yog li ua rau matrix brittle phenomenon hu ua strain-aging type hydrogen embrittlement. Kub-kub yaj mus rau hauv cov khoom tov ntawm hydrogen, nrog rau qhov kub poob nyob rau hauv daim ntawv ntawm hydride nag lossis daus, thiab ua rau titanium alloy ua brittle phenomenon yog hu ua hydride-type hydrogen embrittlement. Ob hom hydrogen embrittlement tuaj yeem tshwm sim hauv titanium thiab titanium alloys.
Qhov teeb meem ntawm hydrogen embrittlement yog tshwm sim los ntawm ntau cov ntsiab lus hydrogen hauv titanium alloys. Yog li ntawd, cov ntsiab lus hydrogen ntawm industrial titanium alloys yuav tsum tau tswj tsis pub dhau 0.015%.
Txhawm rau tiv thaiv lossis txo qis hydrogen embrittlement, lub cub tawg yuav tsum tau ua kom me ntsis oxidizing cua thaum lub sij hawm forging lossis kev kho cua sov, thiab lub tshuab nqus tsev tuaj yeem nqa tawm kom tshem tawm cov hydrogen embrittlement rau titanium alloys nrog cov ntsiab lus hydrogen tshaj cov kev cai raws li qhov tseem ceeb titanium alloy qhov chaw. .