Nrog rau lub zog txhua yam (17.5-19.3 g / cm³), melting point (3422 g / cm³), thiab ultra-siab ceev, tungsten alloy tau lees paub hauv cov tub rog qib siab, aerospace, thiab nuclear engineering fields. Tab sis, nws. Nws tseem cuam tshuam nrog kev ua haujlwm siab. nyuaj. Qhov teeb meem no tshwm sim los ntawm qhov kub thiab txias oxidation, cov ntaub ntawv ua tiav 'tsis kam rau deformation, thiab qhov kub tsis tshua muaj. Yog li ntawd, tungsten tau nkig thiab poob qee qhov ductility, uas ua rau kev ua haujlwm nrog nws nyuaj heev. Raws li kev daws teeb meem, kev lag luam tau tsim cov thev naus laus zis tseem ceeb suav nrog cov hmoov hlau metallurgy, zoo deformation, thiab kev tsim cov yas. Nrog rau cov txheej txheem kom raug thiab sinter ntxiv dag zog, nws muaj peev xwm ua tiav qhov siab precision thiab tungsten nto kev ua haujlwm. Hauv qab no, peb piav qhia txog kev ua haujlwm ntawm tungsten alloy.
1. Powder Metallurgy: Lub hauv paus ntawm kev tsim khoom siab -Purity Billets. Xws li tab sis tsis txwv rau cov haujlwm tseem ceeb hauv qab no, hmoov metallurgy yog thawj kauj ruam hauv kev ua cov tungsten alloys.
1) Purification ntawm Raw Khoom thiab nws cov khoom sib xyaw
High purity tungsten hmoov yog xaiv uas ntau tshaj los yog sib npaug rau 99.95 feem pua thiab ces sib xyaw nrog cov alloying Cheebtsam Nickel, Hlau, thiab Cobalt nyob rau hauv lub chav kawm ntawm pob milling thiab tshuaj ntsuam. Lub formability ntawm cov hmoov yog nyob rau hauv 5 mus rau 10 micron ntau. Rau cov kev siv tshwj xeeb, xws li cov ntaub ntawv siv hauv kev sib xyaw ua ke nuclear, cov theem theem nrab xws li titanium carbide, TiC, thiab Yttrium oxide, Y2O3, yog siv los txhim kho kev sib cais- kom muaj zog tiv thaiv hluav taws xob.
2) Tsim thiab Pre-Sintering
Cov nqi yog npaj siv isostatic nias (siab dua lossis sib npaug ntawm 2500 MPa) lossis tuag- cov txheej txheem nias. Qhov loj me yog 12 × 12 × 400 mm bar lossis daim hlau. Ua ntej-sintering yog ua nyob rau ntawm 1200℃rau ib teev nyob rau hauv ib tug hydrogen cua los pib txhim kho billet zog thiab conductivity.
2. Plastic Processing: Tus yuam sij rau kev kov yeej lub brittleness Bottleneck. Tungsten alloys 'tsis tshua muaj ductility yuav tsum tau ua tiav los ntawm kev siab -kub yas sib sau:
1) Kub thiab sov dov
Kub dov pib ntawm qhov kub thiab txias ntawm 1350-1500 degree. Los ntawm ntau qhov dov hla, daim ntawv tuab yog txo los ntawm 8 hli mus rau 0.5 hli. Cov yob yuav tsum tau preheated rau 100-350℃kom txo tau deformation kuj. Sov rolling (1200 degree) ntxiv refines daim ntawv mus rau 0.2 hli. Graphite los yog molybdenum disulfide lubrication yog txau thoob plaws hauv cov txheej txheem los tiv thaiv kev tawg.
2) Swaging thiab hlau kos duab
Swaging yog ua nyob rau hauv ib qho chaw hydrogen ntawm 1400-1600 degree. Qhov no rotary forging hloov lub billet mus rau hauv ib tug uniform puag ncig bar (kawg txoj kab uas hla 3 hli) nrog ib tug ceev ntawm 18.8-19.2 g / cm³. Hlau kos duab siv cov txheej txheem "sov sov". Tom qab preheating rau 100-350 degree, daim ntawv yog maj mam rub los ntawm ib tug saw stretcher mus rau ib tug finer hlau thickness ntawm tsawg tshaj li 0.06 hli, haum rau daim ntaub ntawv nyob rau hauv electronics thiab teeb pom kev zoo.
3. Sintering txheej txheem: Txhim khu kev ceev thiab kev ua haujlwm zoo. Sintering yog ib qho tseem ceeb hauv kev nce qhov ceev thiab cov yam ntxwv ntawm tungsten alloys. Cov tseem ceeb yog:
(1) Vertical Melting (Nws tus kheej-Inhibited Sintering): Ib qho tam sim no raug xa ncaj qha los ntawm lub billet los tsim Joule cua sov. Raws li qhov tam sim no yog sintered los ntawm tam sim no uas melts. Nws tswj cov suav ntawm cov nplej kom txog li 10,000 txog 20,000 nplej ib mm² thiab qhov ceev ntawm 17.8 txog 18.6 grams ib cm³. Nws yog qhov zoo tagnrho rau cov hlau thiab cov khoom me me.
(2) Spark Plasma Sintering (SPS): Nws muab cov mem tes ntawm cov tam sim no ua ke nrog qee lub siab, thiab ua tiav qhov ceev ceev ntawm qis dua 2000 0 C, nrog cov nplej loj tswj tsawg dua 300 nm thiab kev txhim kho loj heev ntawm kev nkag siab.
3) Ob -Theem Pressureless Sintering: Kub tswj tau nyob rau theem (2300-2700 degree) nyob rau hauv lub tshuab nqus tsev lossis hydrogen cua, ua tiav qhov theoretical ntom ntau tshaj 98%. Nws yog qhov tsim nyog rau cov raj loj loj thiab tshwj xeeb zoo li qhov chaw.
4. Kev Kho Hniav thiab Tshaj Tawm -Kev Ua Haujlwm: Kev Ua Haujlwm thiab Kev Ua Haujlwm
1) Electroplating thiab txheej
Nyob rau hauv teb rau lub tuam txhab electroplating nias yuav tsum tau txo corrosion thiab hnav ntawm oilfield mechanisms, peb tau tsim tungsten alloy electroplating technology. Tungsten alloys muaj cov kua qaub thiab alkali corrosion zoo dua, thiab hnav tsis kam thiab hardness piv rau chrome electroplates. Kub- ntu ntu yuav tsum tau txau nrog oxidant- cov txheej tiv thaiv (xws li silicon-aluminide) kom txo qis kev puas tsuaj oxidation siab tshaj 1000℃.
2) Machining thiab kev kho cua sov
Thaum lub sij hawm txiav, thaum peb siv cov cuab yeej carbide, nws yog ib qho tseem ceeb uas yuav tsum tau nce lub Workpieces saum toj no 200-500 degree, uas yog cov ductile-nkig hloov kub, kom tshem tawm cov kev pheej hmoo ntawm tawg. Tus txheej txheem "aging" txhais tau hais tias lub workpiece yuav tsum tau mus txog ib theem pib ntawm kev hloov kho, uas yog tom qab ntawd los ntawm theem nrab. Piv txwv li, yog tias W-Re alloy yog rhuab mus rau 1500 degree, ces peb paub tias nyob rau hauv nws, peb yuav tsum mus txog rau ib tug kub ntawm 1650 degree.
5. Cov txheej txheem tshiab: Cov lus qhia tshiab hauv kev tshawb fawb
1) Hauv -Situ Reaction Method
Txoj hauv kev no ua rau hauv -situ cov tshuaj tiv thaiv ntawm tungsten hmoov nrog carbon thiab nitrogen los tsim cov tungsten carbide (WC) thiab tungsten nitride (WN) cov theem ntxiv. Cov tshuaj tiv thaiv no txo tus nqi ntawm kev tsim cov khoom sib xyaw.
2) Additive Manufacturing
Txoj kev no siv SLM (xaiv laser melting) tshuab, uas ncaj qha fabricates intricate geometrical qhov chaw. Ua ke nrog lwm cov tswv yim, SLM, nanopowders, thiab gradient tsim daws qhov kev txwv ntawm cov qauv siv.
Ntau qhov kev ua tau zoo, siab - cov ntaub ntawv ua tau zoo yog xav tau rau nuclear fusion reactors thiab hypersonic tsheb, thiab qhov no ua rau kev txhim kho ntawm tungsten alloy processing technology. Los ntawm kev sib koom tes hauv cov hmoov metallurgy, yas tsim, thiab sintering, thiab nyob rau hauv txhua lwm yam kev kho mob saum npoo av, DBTT (ductile -kho hloov kub) ntawm tungsten alloys raug coj los ntawm 400℃thiab qis dua chav tsev kub, txhim kho lawv cov tiv thaiv hluav taws xob thiab oxidation.
