Carbide ndiye gulu lomwe limagwiritsidwa ntchito kwambiri pazida zothamanga kwambiri (HSM), zomwe zimapangidwa ndi njira zopangira zitsulo ndipo zimakhala ndi tinthu tating'onoting'ono ta carbide (kawirikawiri tungsten carbide WC) komanso chitsulo chofewa. Pakadali pano, pali mazana a ma carbides opangidwa ndi simenti opangidwa ndi WC okhala ndi nyimbo zosiyanasiyana, omwe ambiri amagwiritsa ntchito cobalt (Co) ngati chomangira, faifi tambala (Ni) ndi chromium (Cr) ndizomwe zimagwiritsidwanso ntchito kwambiri, ndipo zina zitha kuwonjezedwa. . zinthu zina alloying. Chifukwa chiyani pali magiredi ambiri a carbide? Kodi opanga zida amasankha bwanji chida choyenera pa ntchito inayake yodula? Kuti tiyankhe mafunsowa, tiyeni tione kaye zinthu zosiyanasiyana zomwe zimapanga simenti ya carbide kukhala chida choyenera.
kuuma ndi kulimba
WC-Co cemented carbide ili ndi maubwino apadera pakuuma komanso kulimba. Tungsten carbide (WC) ndi yolimba kwambiri (kuposa corundum kapena alumina), ndipo kuuma kwake sikucheperachepera pamene kutentha kwa ntchito kumawonjezeka. Komabe, ilibe kulimba kokwanira, chinthu chofunikira pakudula zida. Pofuna kupezerapo mwayi pa kuuma kwakukulu kwa tungsten carbide ndikuwongolera kulimba kwake, anthu amagwiritsa ntchito zomangira zachitsulo kuti amangire tungsten carbide palimodzi, kotero kuti zinthuzi zimakhala zolimba kwambiri kuposa zitsulo zothamanga kwambiri, pomwe zimatha kupirira kudula kwambiri. ntchito. kudula mphamvu. Kuphatikiza apo, imatha kupirira kutentha kwakukulu komwe kumayambitsidwa ndi makina othamanga kwambiri.
Masiku ano, pafupifupi mipeni yonse ya WC-Co ndi zoyikapo zidakutidwa, kotero kuti gawo la zinthu zoyambira likuwoneka ngati losafunika. Koma kwenikweni, ndi modulus yotanuka kwambiri ya zinthu za WC-Co (muyeso wa kuuma, womwe ndi pafupifupi katatu kuposa wachitsulo chothamanga kwambiri pa kutentha kwa firiji) womwe umapereka gawo lapansi losapunduka la zokutira. Matrix a WC-Co amaperekanso kulimba kofunikira. Izi ndizomwe zimayambira pazida za WC-Co, koma zida zake zimathanso kusinthidwa posintha kapangidwe kazinthu ndi ma microstructure popanga ufa wa simenti wa carbide. Chifukwa chake, kukwanira kwa magwiridwe antchito pamakina ena kumadalira kwambiri pakupanga mphero koyambirira.
Njira yogaya
Tungsten carbide powder imapezeka ndi carburizing tungsten (W) ufa. Makhalidwe a tungsten carbide ufa (makamaka tinthu kukula kwake) makamaka zimadalira tinthu kukula kwa zopangira tungsten ufa ndi kutentha ndi nthawi carburization. Kuwongolera kwamankhwala ndikofunikira, ndipo zomwe zili mu kaboni ziyenera kukhala zokhazikika (pafupi ndi mtengo wa stoichiometric wa 6.13% polemera). Kuchuluka kwa vanadium ndi/kapena chromium kutha kuwonjezeredwa ku mankhwala a carburizing kuti athe kuwongolera kukula kwa tinthu ting'onoting'ono kudzera m'njira zotsatila. Kusiyanasiyana kwa njira zakutsikira pansi ndi kugwiritsiridwa ntchito kosiyanasiyana kumafunikira kuphatikizika kwa tinthu tating'ono ta tungsten carbide, zomwe zili mu kaboni, zomwe zili ndi vanadium ndi chromium, zomwe zimatha kupanga mitundu yosiyanasiyana ya ufa wa tungsten carbide. Mwachitsanzo, ATI Alldyne, wopanga ufa wa tungsten carbide, amapanga magiredi 23 a ufa wa tungsten carbide, ndipo mitundu ya ufa wa tungsten carbide womwe umasinthidwa malinga ndi zomwe wogwiritsa ntchito umafuna ukhoza kupitilira kasanu kuposa kuchuluka kwa tungsten carbide ufa.
Mukasakaniza ndi kupera tungsten carbide ufa ndi chitsulo chomangira kuti mupange mtundu wina wa ufa wa simenti wa carbide, kuphatikiza kosiyanasiyana kungagwiritsidwe ntchito. Zomwe zimagwiritsidwa ntchito kwambiri ndi cobalt ndi 3% - 25% (chiwerengero cha kulemera), ndipo ngati pakufunika kupititsa patsogolo kukana kwa dzimbiri kwa chida, m'pofunika kuwonjezera faifi tambala ndi chromium. Kuonjezera apo, chomangira chachitsulo chikhoza kupitilizidwa bwino powonjezera zigawo zina za alloy. Mwachitsanzo, kuwonjezera ruthenium ku WC-Co cemented carbide kumatha kukulitsa kulimba kwake popanda kuchepetsa kuuma kwake. Kuchulukitsa zomwe zili mu binder kumathandizanso kulimba kwa simenti ya carbide, koma kumachepetsa kuuma kwake.
Kuchepetsa kukula kwa tungsten carbide particles kungapangitse kuuma kwa zinthuzo, koma kukula kwa tinthu ta tungsten carbide kuyenera kukhala kofanana panthawi ya sintering. Pa sintering, tungsten carbide particles amaphatikizana ndikukula kupyolera mu kusungunuka ndi kubwezeretsanso. Mu ndondomeko yeniyeni sintering, kuti apange zinthu wandiweyani mokwanira, zitsulo chomangira amakhala madzi (otchedwa madzi gawo sintering). Kukula kwa tinthu tating'onoting'ono ta tungsten carbide kumatha kuwongoleredwa powonjezera ma carbides ena osinthika, kuphatikiza vanadium carbide (VC), chromium carbide (Cr3C2), titanium carbide (TiC), tantalum carbide (TaC), ndi niobium carbide (NbC). Ma carbide azitsulowa nthawi zambiri amawonjezeredwa pamene tungsten carbide powder amasakanikirana ndi kuphwanyidwa ndi zitsulo zachitsulo, ngakhale kuti vanadium carbide ndi chromium carbide zimatha kupangidwanso pamene tungsten carbide powder ndi carburized.
Tungsten carbide ufa amathanso kupangidwa pogwiritsa ntchito zinyalala zobwezerezedwanso ndi simenti zida za carbide. Kubwezeretsanso ndi kugwiritsiranso ntchito scrap carbide kwakhala ndi mbiri yakale mumakampani opanga simenti ya carbide ndipo ndi gawo lofunikira pazachuma chonse chamakampani, kuthandiza kuchepetsa ndalama zakuthupi, kupulumutsa zachilengedwe ndikupewa kuwononga zinthu. Kutaya kovulaza. Carbide yokhala ndi simenti imatha kugwiritsidwanso ntchito ndi njira ya APT (ammonium paratungstate), njira yobwezeretsa zinki kapena kuphwanya. Tungsten carbide powders "obwezerezedwanso" awa nthawi zambiri amakhala ndi kachulukidwe kabwinoko, kodziwikiratu chifukwa amakhala ndi malo ang'onoang'ono kuposa ufa wa tungsten carbide wopangidwa mwachindunji kudzera munjira ya tungsten carburizing.
Zomwe zimapangidwira pakugaya kosakanikirana kwa tungsten carbide ufa ndi zitsulo zomangira ndizofunikanso kwambiri. Njira ziwiri zomwe zimagwiritsidwa ntchito kwambiri mphero ndi mphero ya mpira ndi micromilling. Onse njira zimathandiza yunifolomu kusanganikirana wa milled ufa ndi kuchepetsedwa tinthu kukula. Kuti apange workpiece yomwe yatsatiridwa pambuyo pake ikhale ndi mphamvu zokwanira, kusunga mawonekedwe a workpiece, ndikupangitsa woyendetsa kapena woyendetsa kuti atenge ntchitoyo kuti agwire ntchito, nthawi zambiri zimakhala zofunikira kuwonjezera chomangira cha organic panthawi yopera. The mankhwala zikuchokera chomangira zingakhudze kachulukidwe ndi mphamvu ya mbamuikha workpiece. Kuti muthandizire kuwongolera, ndikofunikira kuwonjezera zomangira zolimba kwambiri, koma izi zimapangitsa kuti pakhale kuchepa kwapang'onopang'ono ndipo zitha kutulutsa zipsera zomwe zingayambitse zolakwika pazomaliza.
Pambuyo mphero, ufa nthawi zambiri utsi-zouma kupanga ufulu-oyenda agglomerates wogwiridwa pamodzi ndi organic binders. Ndi kusintha zikuchokera organic binder, ndi flowability ndi mlandu kachulukidwe wa agglomerates izi akhoza ogwirizana monga ankafuna. Ndi kuwunika kunja coarser kapena bwino particles, ndi tinthu kukula kugawa agglomerate akhoza zina ogwirizana kuonetsetsa otaya bwino pamene yodzaza mu nkhungu patsekeke.
Kupanga ntchito
Carbide workpieces amatha kupangidwa ndi njira zosiyanasiyana. Kutengera ndi kukula kwa workpiece, mulingo wa zovuta mawonekedwe, ndi kupanga mtanda, ambiri kudula amaika ndi kuumbidwa pogwiritsa ntchito pamwamba ndi pansi-anzanu okhwima amafa. Pofuna kusunga kugwirizana kwa workpiece kulemera ndi kukula pa kukanikiza kulikonse, m'pofunika kuonetsetsa kuti kuchuluka kwa ufa (misa ndi voliyumu) oyenderera mu patsekeke ndi chimodzimodzi. The fluidity wa ufa makamaka ankalamulidwa ndi kukula kugawa agglomerates ndi katundu wa organic binder. Zopangira zoumba (kapena "zopanda kanthu") zimapangidwa pogwiritsa ntchito mphamvu ya 10-80 ksi (kilo pounds pa phazi lalikulu) ku ufa wolowetsedwa mu nkhungu.
Ngakhale pansi kwambiri akamaumba kupanikizika, zolimba tungsten carbide particles sadzasintha kapena kusweka, koma organic binder mbamuikha mu mipata pakati pa tungsten carbide particles, potero kukonza malo a particles. Kuthamanga kwapamwamba, kumamatira kumangiriza kwa tinthu tating'ono ta tungsten carbide ndipo kumapangitsanso kachulukidwe kake ka workpiece. The akamaumba zimatha sukulu ya simenti ufa carbide zingasiyane, kutengera zili zitsulo binder, kukula ndi mawonekedwe a tungsten carbide particles, mlingo wa agglomeration, ndi zikuchokera ndi Kuwonjezera organic binder. Pofuna kupereka chidziwitso chochuluka chokhudza kuphatikizika kwa ufa wa carbide, mgwirizano pakati pa kachulukidwe kameneka ndi kukakamiza kowumba nthawi zambiri kumapangidwa ndikupangidwa ndi wopanga ufa. Chidziwitsochi chimatsimikizira kuti ufa woperekedwa umagwirizana ndi njira yopangira zida.
Zogwirira ntchito zazikuluzikulu za carbide kapena zogwirira ntchito za carbide zokhala ndi mawonekedwe apamwamba (monga ziboliboli za mphero ndi zobowolera) nthawi zambiri zimapangidwa kuchokera ku ufa wa carbide woponderezedwa m'chikwama chosinthika. Ngakhale kuti njira yopangira njira yopondereza yokhazikika ndi yayitali kuposa njira yopangira, mtengo wopangira chida ndi wotsika, kotero njira iyi ndi yoyenera kupanga magulu ang'onoang'ono.
Njirayi ndiyo kuyika ufa mu thumba, ndikusindikiza pakamwa pa thumba, ndikuyika thumba lodzaza ndi ufa mu chipinda, ndikugwiritsira ntchito mphamvu ya 30-60ksi kudzera mu chipangizo cha hydraulic kuti musindikize. Ma workpieces oponderezedwa nthawi zambiri amapangidwa ndi ma geometries ena asanawombedwe. Kukula kwa thumba kumakulitsidwa kuti agwirizane ndi kuchepa kwa zogwirira ntchito panthawi yophatikizika ndikupereka malire okwanira pogaya. Popeza kuti workpiece iyenera kukonzedwa pambuyo pa kukanikiza, zofunikira kuti zisagwirizane ndi zolipiritsa sizili zolimba monga za njira yopangira, komabe ndizofunikira kuonetsetsa kuti ufa womwewo umayikidwa mu thumba nthawi iliyonse. Ngati kuchulukitsitsa kwa ufawo kuli kochepa kwambiri, kungayambitse ufa wosakwanira m'thumba, zomwe zimapangitsa kuti chogwiriracho chikhale chochepa kwambiri ndipo chiyenera kuchotsedwa. Ngati kachulukidwe kachulukidwe ka ufa ndi wochuluka kwambiri, ndipo ufa womwe umayikidwa mu thumba ndi wochuluka, chogwirira ntchito chiyenera kukonzedwa kuti chichotse ufa wochuluka pambuyo popanikizidwa. Ngakhale ufa wowonjezera womwe umachotsedwa ndikutayidwa ukhoza kubwezeretsedwanso, kutero kumachepetsa zokolola.
Carbide workpieces amathanso kupangidwa pogwiritsa ntchito extrusion kufa kapena jekeseni kufa. The extrusion akamaumba ndondomeko ndi oyenera kwambiri kupanga misa axisymmetric mawonekedwe workpieces, pamene jekeseni akamaumba ndondomeko nthawi zambiri ntchito kupanga unyinji wa workpieces mawonekedwe zovuta. M'njira zonse ziwirizi, ufa wa cemented carbide umayimitsidwa mu organic binder yomwe imapangitsa kusakanikirana kwa mankhwala otsukira mano kusakanikirana ndi simenti ya carbide. Pawiri ndiye mwina extruded kudzera dzenje kapena jekeseni mu dzenje kuti apange. Makhalidwe a kalasi ya simenti ufa carbide kudziwa momwe akadakwanitsira chiŵerengero cha ufa kuti binder mu osakaniza, ndi chidwi kwambiri pa flowability wa osakaniza mwa dzenje extrusion kapena jekeseni mu patsekeke.
Pambuyo pa workpiece apangidwa ndi akamaumba, isostatic kukanikiza, extrusion kapena jekeseni akamaumba, organic binder ayenera kuchotsedwa workpiece isanafike sintering siteji yomaliza. Sintering imachotsa porosity kuchokera pa workpiece, ndikupangitsa kuti ikhale yodzaza (kapena kwambiri) wandiweyani. Pa sintering, zitsulo chomangira mu atolankhani anapanga workpiece amakhala madzi, koma workpiece lokhalabe mawonekedwe ake pansi pa ophatikizana zochita za capillary mphamvu ndi tinthu kugwirizana.
Pambuyo pa sintering, geometry ya workpiece imakhala yofanana, koma miyeso imachepetsedwa. Kuti mupeze kukula kofunikira kwa workpiece pambuyo pa sintering, mlingo wa shrinkage uyenera kuganiziridwa popanga chida. Gulu la ufa wa carbide womwe umagwiritsidwa ntchito popanga chida chilichonse uyenera kupangidwa kuti ukhale ndi shrinkage yolondola ikaphatikizidwa pansi pa zovuta zoyenera.
Pafupifupi nthawi zonse, chithandizo cha post-sintering cha sintered workpiece chimafunika. Chithandizo chofunikira kwambiri cha zida zodulira ndikunola m'mphepete. Zida zambiri zimafunikira kugaya ma geometry awo ndi miyeso yawo pambuyo pa sintering. Zida zina zimafuna kugaya pamwamba ndi pansi; zina zimafuna kugaya zotumphukira (monga kapena popanda kunola m'mphepete mwake). Tchipisi zonse za carbide zochokera kukupera zitha kubwezeredwa.
Chophimba cha workpiece
Nthawi zambiri, ntchito yomalizidwa iyenera kuphimbidwa. Chophimbacho chimapereka lubricity ndi kuwonjezeka kuuma, komanso chotchinga kufalikira kwa gawo lapansi, kuteteza makutidwe ndi okosijeni pamene akutentha kwambiri. Gawo la simenti la carbide ndilofunika kwambiri pakugwira ntchito kwa zokutira. Kuphatikiza pa kukonza zinthu zazikulu za ufa wa matrix, mawonekedwe a pamwamba a matrix amathanso kukonzedwa ndi kusankha mankhwala ndikusintha njira ya sintering. Kupyolera mu kusamuka kwa cobalt, cobalt wochuluka akhoza kulemeretsedwa kunja wosanjikiza wa tsamba pamwamba pa makulidwe a 20-30 μm poyerekeza ndi zina zonse workpiece, potero kupereka pamwamba pa gawo lapansi mphamvu bwino ndi kulimba, kupangitsa kuti kwambiri. kugonjetsedwa ndi deformation.
Kutengera njira zawo zopangira (monga njira yothira matope, kuchuluka kwa kutentha, nthawi ya sintering, kutentha ndi voteji ya carburizing), wopanga zida atha kukhala ndi zofunika zina zapadera pagawo la ufa wa carbide wogwiritsidwa ntchito. Ena opanga zida amatha kuyimitsa chogwiriracho mu ng'anjo ya vacuum, pomwe ena angagwiritse ntchito ng'anjo yotentha ya isostatic (HIP) (yomwe imakakamiza chogwirira ntchito chakumapeto kwa njira kuti achotse zotsalira) pores). Zogwirira ntchito zomwe zimayikidwa mu ng'anjo ya vacuum zingafunikirenso kutenthedwa mwachisawawa kudzera munjira yowonjezera kuti muwonjezere kachulukidwe ka ntchitoyo. Opanga zida ena atha kugwiritsa ntchito kutentha kwa vacuum sintering kuti awonjezere kuchuluka kwa zosakaniza zomwe zili ndi cobalt yotsika, koma njira iyi imatha kukulitsa mawonekedwe awo. Kuti musunge kukula kwambewu, ma ufa okhala ndi tinthu tating'onoting'ono ta tungsten carbide amatha kusankhidwa. Kuti zigwirizane ndi zida zenizeni zopangira, ma dewaxing ndi voteji ya carburizing alinso ndi zofunikira zosiyanasiyana pazakudya za kaboni mu ufa wa simenti wa carbide.
Gulu la kalasi
Kusintha kophatikizana kwamitundu yosiyanasiyana ya ufa wa tungsten carbide, kuphatikizika kosakanikirana ndi zitsulo zomangira zitsulo, mtundu ndi kuchuluka kwa zoletsa kukula kwambewu, ndi zina zotere, zimapanga mitundu yosiyanasiyana ya simenti ya carbide. Izi magawo adzazindikira microstructure wa simenti carbide ndi katundu wake. Kuphatikizika kwina kwazinthu kwakhala kofunikira kwambiri pamapulogalamu ena apadera, zomwe zimapangitsa kuti zikhale zomveka kuyika magulu osiyanasiyana opangidwa ndi simenti ya carbide.
Mitundu iwiri ya carbide yomwe imagwiritsidwa ntchito kwambiri pamakina opangira makina ndi makina a C ndi mawonekedwe a ISO. Ngakhale palibe dongosolo lomwe likuwonetsa bwino zinthu zomwe zimakhudza kusankha kwa simenti ya carbide, zimapereka poyambira kukambirana. Pagulu lililonse, opanga ambiri ali ndi magiredi awo apadera, zomwe zimapangitsa kuti pakhale mitundu yosiyanasiyana ya carbide.
Makalasi a Carbide amathanso kugawidwa molingana ndi kapangidwe kake. Makalasi a Tungsten carbide (WC) amatha kugawidwa m'mitundu itatu: yosavuta, microcrystalline ndi alloyed. Makalasi a Simplex makamaka amakhala ndi tungsten carbide ndi cobalt binders, koma atha kukhalanso ndi zoletsa zoletsa kukula kwambewu. Gulu la microcrystalline limapangidwa ndi tungsten carbide ndi cobalt binder zowonjezeredwa ndi masauzande angapo a vanadium carbide (VC) ndi (kapena) chromium carbide (Cr3C2), ndipo kukula kwake kwambewu kumatha kufika 1 μm kapena kuchepera. Makalasi a aloyi amapangidwa ndi tungsten carbide ndi cobalt zomangira zomwe zili ndi titanium carbide (TiC), tantalum carbide (TaC), ndi niobium carbide (NbC). Zowonjezera izi zimadziwikanso kuti cubic carbides chifukwa cha mawonekedwe awo a sintering. The chifukwa microstructure amasonyeza inhomogeneous magawo atatu dongosolo.
1) Makalasi osavuta a carbide
Makalasi odula zitsulo awa amakhala ndi 3% mpaka 12% cobalt (kulemera kwake). Kukula kwa mbewu za tungsten carbide nthawi zambiri kumakhala pakati pa 1-8 μm. Monga momwe zimakhalira ndi magiredi ena, kuchepetsa kukula kwa tungsten carbide kumawonjezera kuuma kwake komanso kuphulika kwamphamvu (TRS), koma kumachepetsa kulimba kwake. Kuuma kwa mtundu woyera nthawi zambiri kumakhala pakati pa HRA89-93.5; mphamvu yoduka yodutsa nthawi zambiri imakhala pakati pa 175-350ksi. Ufa wamaguluwa ukhoza kukhala ndi zinthu zambiri zobwezerezedwanso.
Magiredi osavuta amtundu amatha kugawidwa mu C1-C4 mu dongosolo la C giredi, ndipo amatha kugawidwa molingana ndi mndandanda wa K, N, S ndi H mu dongosolo la ISO. Magiredi a Simplex okhala ndi zinthu zapakatikati atha kugawidwa ngati magiredi acholinga chambiri (monga C2 kapena K20) ndipo atha kugwiritsidwa ntchito potembenuza, mphero, kupanga mapulani ndi kutopa; magiredi okhala ndi timbewu tating'onoting'ono kapena zocheperako za cobalt komanso kuuma kwakukulu zitha kuwerengedwa ngati zomaliza (monga C4 kapena K01); magiredi okhala ndi tirigu wokulirapo kapena kuchuluka kwa cobalt komanso kulimba kwabwinoko kumatha kugawidwa ngati magiredi ovuta (monga C1 kapena K30).
Zida zopangidwa m'makalasi a Simplex zitha kugwiritsidwa ntchito popanga chitsulo chosapanga dzimbiri, 200 ndi 300 mndandanda wazitsulo zosapanga dzimbiri, aluminiyamu ndi zitsulo zina zopanda chitsulo, ma superalloys ndi zitsulo zolimba. Magirediwa atha kugwiritsidwanso ntchito popanga zitsulo zopanda zitsulo (mwachitsanzo ngati zida zobowola miyala ndi miyala), ndipo magirediwa ali ndi kukula kwambewu kwa 1.5-10μm (kapena kukulirapo) ndi cobalt 6% -16%. Wina wopanda zitsulo kudula ntchito yosavuta carbide giredi ndi kupanga kufa ndi nkhonya. Magirediwa nthawi zambiri amakhala ndi tirigu wapakatikati wokhala ndi cobalt 16% -30%.
(2) Microcrystalline simenti carbide sukulu
Maphunziro oterewa amakhala ndi 6% -15% cobalt. Panthawi ya sintering yamadzimadzi, kuwonjezera kwa vanadium carbide ndi/kapena chromium carbide kumatha kuwongolera kukula kwambewu kuti mupeze mbewu yabwino yokhala ndi tinthu ting'onoting'ono tochepera 1 μm. Gulu lopangidwa bwinoli lili ndi kuuma kwambiri komanso mphamvu zong'ambika zodutsa pamwamba pa 500ksi. Kuphatikizika kwamphamvu kwambiri komanso kulimba kokwanira kumapangitsa kuti magirediwa agwiritse ntchito ngodya yokulirapo, yomwe imachepetsa mphamvu zodulira ndikupanga tchipisi tocheperako podula osati kukankhira zitsulo.
Kudzera okhwima khalidwe chizindikiritso cha zipangizo zosiyanasiyana zopangira kupanga sukulu simenti ufa carbide, ndi kulamulira okhwima sintering zinthu ndondomeko kupewa mapangidwe abnormally lalikulu mbewu mu microstructure zakuthupi, n'zotheka kupeza zinthu zoyenera zakuthupi. Pofuna kusunga kukula kwa mbewu zazing'ono ndi yunifolomu, ufa wobwezerezedwanso uyenera kugwiritsidwa ntchito pokhapokha ngati pali kulamulira kwathunthu kwa zopangira ndi kuchira, komanso kuyesa kwakukulu kwa khalidwe.
Magiredi a microcrystalline amatha kugawidwa molingana ndi mndandanda wa M kalasi ya ISO. Kuonjezera apo, njira zina zamagulu mu C grade system ndi ISO grade system ndizofanana ndi magiredi oyera. Magiredi a Microcrystalline angagwiritsidwe ntchito kupanga zida zomwe zimadula zida zofewa, chifukwa pamwamba pa chidacho zimatha kupangidwa bwino kwambiri ndipo zimatha kukhala zodula kwambiri.
Magiredi a Microcrystalline atha kugwiritsidwanso ntchito kupangira ma superalloys opangidwa ndi faifi tambala, chifukwa amatha kupirira kutentha mpaka 1200 ° C. Pokonza ma superalloys ndi zida zina zapadera, kugwiritsa ntchito zida za kalasi ya microcrystalline ndi zida zoyera zomwe zili ndi ruthenium zimatha kusintha nthawi imodzi kukana kwawo kuvala, kukana mapindikidwe komanso kulimba. Magiredi a Microcrystalline ndi oyeneranso kupanga zida zozungulira monga kubowola komwe kumapangitsa kumeta ubweya wa ubweya. Pali kubowola kopangidwa ndi mitundu yambiri ya simenti ya carbide. M'magawo enaake a kubowola komweko, zomwe zili mu cobalt zimasiyanasiyana, kotero kuti kuuma ndi kulimba kwa kubowola kumakongoletsedwa malinga ndi zofunikira pakukonza.
(3) Aloyi mtundu simenti carbide sukulu
Maphunzirowa amagwiritsidwa ntchito kwambiri podula zigawo zachitsulo, ndipo zomwe zili ndi cobalt nthawi zambiri zimakhala 5% -10%, ndipo kukula kwambewu kumachokera ku 0.8-2μm. Powonjezera 4% -25% titanium carbide (TiC), chizolowezi cha tungsten carbide (WC) kuti chifalikire pamwamba pa tchipisi tachitsulo chikhoza kuchepetsedwa. Mphamvu ya zida, kukana kuvala kwa crater ndi kukana kugwedezeka kwamafuta kumatha kupitilizidwa powonjezera mpaka 25% tantalum carbide (TaC) ndi niobium carbide (NbC). Kuwonjezera amenewa kiyubiki carbides kumawonjezera wofiira kuuma kwa chida, kuthandiza kupewa mapindikidwe matenthedwe chida mu kudula katundu kapena ntchito zina kumene kudula m'mphepete adzapanga kutentha kwambiri. Kuphatikiza apo, titaniyamu carbide imatha kupereka malo a nucleation panthawi ya sintering, kuwongolera kufanana kwa kugawa kwa cubic carbide mu workpiece.
Nthawi zambiri, kuuma kwamtundu wa aloyi-mtundu wa simenti wa carbide ndi HRA91-94, ndipo mphamvu yodutsa yosweka ndi 150-300ksi. Poyerekeza ndi magiredi abwino, ma alloy giredi samatha kuvala bwino komanso mphamvu zochepa, koma amakana kuvala zomatira. Aloyi magiredi akhoza kugawidwa mu C5-C8 mu C giredi dongosolo, ndipo akhoza m'gulu la P ndi M kalasi mndandanda mu dongosolo ISO giredi. Makalasi a aloyi okhala ndi zinthu zapakatikati amatha kugawidwa ngati magiredi ofunikira (monga C6 kapena P30) ndipo atha kugwiritsidwa ntchito kutembenuza, kugogoda, kukonza ndi mphero. Magiredi ovuta kwambiri amatha kugawidwa ngati magiredi omaliza (monga C8 ndi P01) pomaliza ntchito zotembenuza ndi zotopetsa. Magiredi awa nthawi zambiri amakhala ndi kukula kwambewu kakang'ono komanso kutsika kwa cobalt kuti apeze kulimba kofunikira komanso kukana kuvala. Komabe, zinthu zofananira zimatha kupezeka powonjezera ma cubic carbides. Magiredi olimba kwambiri amatha kugawidwa ngati magiredi ovuta (mwachitsanzo C5 kapena P50). Magiredi awa nthawi zambiri amakhala ndi tirigu wapakatikati komanso kuchuluka kwa cobalt, zokhala ndi zowonjezera zochepa za ma cubic carbides kuti akwaniritse kulimba komwe kumafunikira poletsa kukula kwa crack. Pakutembenuka kosokonekera, ntchito yodulira imatha kupitilizidwa bwino pogwiritsa ntchito magiredi olemera a cobalt omwe tawatchulawa omwe ali ndi cobalt yapamwamba pazida.
Aloyi magiredi okhala ndi titanium carbide yotsika amagwiritsidwa ntchito popanga chitsulo chosapanga dzimbiri ndi chitsulo chosungunula, komanso amathanso kugwiritsidwa ntchito popanga zitsulo zopanda chitsulo monga ma superalloys opangidwa ndi faifi tambala. Kukula kwa mbewu zamaguluwa nthawi zambiri kumakhala kosakwana 1 μm, ndipo cobalt ndi 8% -12%. Magiredi olimba, monga M10, atha kugwiritsidwa ntchito potembenuza chitsulo chosungunuka; magiredi olimba, monga M40, atha kugwiritsidwa ntchito pogaya ndi kupanga zitsulo, kapena kutembenuza chitsulo chosapanga dzimbiri kapena ma superalloys.
Aloyi-mtundu cemented carbide giredi angagwiritsidwenso ntchito osati zitsulo kudula, makamaka kupanga ziwiya kuvala kuvala. Kukula kwa tinthu tamaphunzirowa nthawi zambiri ndi 1.2-2 μm, ndipo cobalt ndi 7% -10%. Popanga magirediwa, kuchuluka kwa zinthu zokazinganso nthawi zambiri kumawonjezeredwa, zomwe zimapangitsa kuti pakhale zotsika mtengo kwambiri pazigawo zovala. Zida zobvala zimafunikira kukana bwino kwa dzimbiri komanso kuuma kwakukulu, komwe kungapezeke powonjezera faifi tambala ndi chromium carbide popanga magirediwa.
Kuti akwaniritse zofunikira zaukadaulo ndi zachuma za opanga zida, ufa wa carbide ndiye chinthu chofunikira kwambiri. Ufa wopangidwira zida zopangira zida za opanga zida ndi magawo opangira amawonetsetsa kuti ntchito yomalizidwayo imagwira ntchito ndipo zapangitsa kuti ma carbide achulukane. Mkhalidwe wobwezerezedwanso wa zinthu za carbide komanso kuthekera kogwira ntchito mwachindunji ndi ogulitsa ufa amalola opanga zida kuti azitha kuwongolera bwino mtundu wawo wazinthu ndi mtengo wazinthu.
Nthawi yotumiza: Oct-18-2022
