Momwe Mungapangire Tungsten Carbide?

    Zogulitsa za Tungsten Carbide zimagwiritsidwa ntchito pazinthu zambiri, kuphatikiza zida zodulira, kubowola, kukhomerera, ndi zina zambiri. Cemented Carbide imapereka kukana kovala bwino komanso kumatalikitsa moyo wa zida zosiyanasiyana izi zobvala ndi kudula. Chifukwa chigawo chake chachikulu ndi tungsten, chomwe ndi chinthu chosowa komanso chosasinthika, mtengo wa simenti wa carbide ndi wokwera kwambiri. Kuphatikiza apo, carbide yopangidwa ndi simenti imakhala yolimba kwambiri, ndipo mphamvu yopindika ndiyotsika kwambiri kuposa zitsulo zina, monga chitsulo. Pazifukwa ziwirizi, carbide yopangidwa ndi simenti iyenera kulumikizidwa ndi zitsulo zina mwanjira zosiyanasiyana, monga kulumikiza ulusi, kuwotcherera, ndi kuwotcherera. Nkhaniyi ikukamba za momwe mungapangire tungsten carbide pazitsulo zina.

1. Kodi tungsten carbide ndi chiyani?

    Tungsten carbide (WC), yomwe imatchedwanso cemented carbide, ndi chinthu chophatikizika chopangidwa ndi njira yotchedwa powder metallurgy. Ufa wa WC umasakanizidwa ndi chitsulo chomangira, nthawi zambiri cobalt kapena faifi tambala, wopangidwa ndi zida za preform, kenako ndikuwotchedwa mu ng'anjo. Mawu akuti "simenti" amatanthauza particles tungsten carbide kugwidwa mu zitsulo binder zakuthupi ndi "simenti" palimodzi, kupanga chomangira zitsulo pakati pa tungsten carbide particles ndi binder (WC-Co), mu ndondomeko sintering. Makampani opangidwa ndi simenti amatchula zinthu izi ngati "carbide", ngakhale mawu akuti tungsten carbide ndi simenti carbide amagwiritsidwa ntchito mosiyana.  Carbide imawonetsa mphamvu zopondereza kwambiri, imakana kupotoza, ndipo imasungabe kuuma kwake pakatentha kwambiri, chinthu chomwe chili chofunikira kwambiri pakudula zitsulo. 

2 . Mfundo ziwiri zowonetsetsa kuti mukuchita bwino pakuwotcha tungsten carbide

A. Kuwongolera kupsinjika komwe kumachitika chifukwa chakukula kosiyanasiyana

B. Kutsika mitengo ya zida za makolo ndi kunyowetsa kwa carbide ndi aloyi ya braze

    Panthawi yotentha ndi kuziziritsa, zitsulo zoyambira zimakulirakulira ndikucheperachepera kuposa carbide.  Tungsten carbide ili ndi kuchuluka kwa kutentha kwa pafupifupi 1/3 mpaka 1/2 yachitsulo.  Msonkhano wa brazed ukazizira, kupsinjika kotsalira kumatha kumangika mkati mwa carbide.  Kuzizira pang'onopang'ono kwa carbide kumalimbikitsidwa nthawi zonse kuti mupewe kupsinjika komanso kusweka kotheka. Kuzimitsa sikovomerezeka chifukwa kungayambitse ming'alu ya carbides chifukwa cha kugunda kwachangu kwazitsulo zazitsulo za makolo.

3. Momwe mungasankhire alloy braze

    Tungsten carbide ndizovuta kunyowa. Zosakaniza za siliva zokhala ndi zowonjezera zazing'ono za Nickel (Ni) zimagwiritsidwa ntchito popanga ma carbides kukhala chitsulo. Zoonadi, zonse ziwiri za carbide ndi zitsulo ziyenera kukhala zoyera kuti alloy yosungunuka imatha kunyowetsa malo okwerera kwathunthu. Kupukuta pamwamba pa carbide kuti pakhale malo oyera opangira brazing ndikofunikira. Kupera kumakhalanso ndi mwayi wowongolera pamwamba pa carbide, yomwe ingathandize ndi kunyowetsa alloy braze ndi kumamatira. Zida zachitsulo, mofananamo, ziyenera kutsukidwa kuti zichotse mafuta otsalira, mafuta, dothi, kapena zowononga zina.  

    ·Ma aloyi asiliva omwe amapezeka pamalonda okhala ndi nickel (Ni) ndi Manganese (Mn) amatha kunyowa mosavuta pamalo otetezedwa ndi simenti. Ma aloyi amkuwa awa amawonetsa kunyowetsa kwabwino kwa tungsten carbides.  Ndibwino kuti musankhe chitsulo chodzaza ndi brazing ndi kutentha kotsika kwambiri kuti muchepetse zovuta zotsalira mkati mwa mgwirizano.  

Za applima cations okhudzana ndi kuwomba kwa carbides akulu, aloyi ya sandwich braze imagwiritsidwa ntchito nthawi zambiri.  Ngati ma carbides ang'onoang'ono (1/2 inchi2) sangathe kugwiritsidwa ntchito, aloyi ya sandwich imathandiza kupewa kusweka ndi kuphulika kwa carbide. Ma trimetal awa amavekedwa ndi chodzaza chamkuwa chomangika mbali zonse za pachimake chamkuwa.  

    ·Ngakhale kuti zokambirana zambiri zakhala zikuzunguliridwa ndi tungsten carbide (WC), tingakhale olakwika ngati sitinatchulepo polycrystalline diamondi kapena PCD. Kutentha kwamphamvu kwa PCD nthawi zambiri kumasungidwa pansi pa 1382 ° F (750 ° C) kupewa kuwonongeka kwa diamondi.  Nthawi zambiri, opanga malangizo a PCD ku matupi achitsulo amagwiritsa ntchito chitsulo chotsika kwambiri, chapamwamba cha siliva, monga BAg-24 braze alloy.  Ena opanga amagwiritsa ntchito alloy braze popanda faifi tambala kapena manganese, monga BAg-5 kapena BAg-7 braze alloy, ndi kutentha kutsika kusungunuka komanso kunyowetsa pang'ono kwa carbide ndi chitsulo.

    Kuthamanga kwa brazing kumagwiritsidwa ntchito poletsa makutidwe ndi okosijeni a malo omwe amalumikizidwa pakuwotcha kwa msonkhano.  Flux ufa amagwiritsidwa ntchito ndi ma alloys wamba asiliva braze.  Ufa wakuda wakuda umalimbikitsidwa ndi opanga braze ndi flux popeza uli ndi kuwonjezera kwa boron ndipo ndi wothandiza kwambiri pakutentha kwambiri.

    Pali ma alloys angapo omwe amagwiritsidwa ntchito popanga carbide. Zachikale ndi BAG-3, 50% siliva ndi Cadmium.  Ichi ndi chinthu chabwino kwambiri, koma chili ndi Cadmium. Nthawi zambiri amagwiritsidwa ntchito ndi BAG-7, 56% siliva yokhala ndi Tini, chifukwa imanyowa mosavuta; komabe, ndi aloyi ofooka kwambiri, ndipo kulephera kwamagulu kumakhala kofala ndi aloyiyi. Aloyi yamphamvu kwambiri yopanda Cadmium ndi BAG-22, siliva 49% yokhala ndi manganese, koma imakhala ngati chingamu. BAG-24, 50% Silver, alibe cadmium ndipo ndi kunyengerera.  Imayenda bwino koma ndi pafupifupi 40% yofooka kuposa BAG-3 ndi BAG-22.

    Timakonda kwambiri Black Flux, ngakhale ambiri amalimba bwino ndi White Flux. Muzochitika zonsezi, ndizowoneka bwino kutentha kwapamwamba. Kuphatikiza apo, n timapeza kuti Black Flux yoyeretsedwa imapereka kuyenda kwabwinoko komanso malo olumikizirana mwamphamvu kuposa Black Flux wamba.  

    Malo omaliza omwe zolakwika zimakhala zofala ndizomwe zimapangidwira pamodzi. Owotcherera ophunzitsidwa nthawi zambiri amafuna kusonkhanitsa zigawozo kenako ndikuyendetsa mkanda. Akamawombera, amafuna kusonkhanitsa zigawozo ndiyeno amawotcha aloyi yachitsulo mu mgwirizano.   

    Mukawotcha carbide, nthawi zambiri zimakhala zogwira mtima kwambiri kusuntha mbali ndi pansi pa notch, ndikuyika zidutswa za waya wa alloy pansi pa carbide.  Zonse zomwe mumachita ndi kutentha mpaka carbide itakhazikika.   

    Muyezo uyenera kukhala kuti carbide imaphulika kapena zitsulo zimang'ambika kuti mgwirizano uwonongeke.