Anthu akamva mawu akuti "mu powder metallurgy", nthawi zambiri amajambula mwaudongo, wamakono --press powder, sinter, done. Zowona m'malo ogulitsira ndizovuta kwambiri, zodzaza ndi zosagwirizana ndipo 'zimadalira' nthawi zomwe mapepala samabisa.
Kusiyana Pakati pa Spec ndi Zowona
Tengani kachulukidwe, mwachitsanzo. Aliyense amathamangitsa theoretical 100% dense gawo. Koma muzochita, kukwaniritsa kachulukidwe yunifolomu, makamaka mu ma geometries ovuta, ndi nkhondo yosalekeza. Mutha kukhala ndi mayitanidwe apadera a 7.2 g/cm3, ndipo mumagunda pafupifupi. Komabe, gawaniza gawolo, ndipo mupeza ma gradients - zigawo zoonda kwambiri zikuyenda mosiyana ndi malo akulu akulu. Uku sikulephera kwa ndondomekoyi mu powder metallurgy mwa munthu, koma chikhalidwe chofunikira. Kapangidwe ka zida, kudzaza, kugunda kwa atolankhani - zonse zimasiya zala zawo. Ndawonapo zigawo zikudutsa QA pamiyeso ndi kachulukidwe wapakati, ndikulephera pakuyesa kutopa chifukwa cha kachulukidwe kakang'ono kamene kali pamtunda. Ndi pamene ntchito yeniyeni imayambira.
Izi zikugwirizana ndi malingaliro olakwika a kasitomala. Amatumiza chojambula cha gawo lopangidwa ndi makina ndikufunsa, Kodi mungapange izi kudzera pa PM kuti mupulumutse mtengo? Nthawi zina, inde. Koma nthawi zambiri, mapangidwewo amakhala ndi ngodya zakuthwa, makulidwe a khoma osafanana, kapena mawonekedwe omwe amafunikira makina achiwiri. Mtengo weniweni mu powder metallurgy ikukonzekera ndondomekoyi kuyambira pachiyambi-kuphatikiza zojambula, kukhathamiritsa kusintha kwa khoma, ndikuwonetseratu kulolerana komwe ndondomekoyi ingathe kugwira popanda kuisintha kukhala pulojekiti yokonza makina. Ndi njira yolumikizirana yomwe nthawi zambiri imadumphidwa pothamangira mawu.
Kusankha kwazinthu ndi malo ena okhwima ndi nuance. Zosakaniza zachitsulo-mkuwa-carbon ndi zogwirira ntchito, koma mukafuna kukana dzimbiri kapena kutentha kwambiri, mumalowa muzitsulo zokhala ndi alloyed kapena zosapanga dzimbiri. Nayi mwatsatanetsatane: ndi 316L ufa wosapanga dzimbiri, mpweya wozizira umakhala wovuta. Kudontha kwakung'ono m'ng'anjo, mpweya wotsalira pang'ono, ndipo simumangosintha mawonekedwe - mumapeza mapangidwe a chromium oxide omwe amachotsa kukana kwa dzimbiri kuchokera pachimake. Izo zikuwoneka bwino kutuluka mu ng'anjo, koma izo zichita dzimbiri. Mumaphunzira kukhulupirira ma analyzer a dew point kuposa maso anu.
Kumene PM Amakumana ndi Unyolo Wambiri Wopanga
Apa ndipamene ukadaulo wa wopanga ntchito zonse umakhala wofunikira. Gawo silimabadwira mu ng'anjo yoyaka moto ndipo limatchedwa lathunthu. Tengani sprocket kapena zida zopangidwa mu powder metallurgy. Zingafunikire kubowoledwa kuti mutsirize bwino, njira yotsekera, kapena kugwetsa mano. Ngati sintering sichiwongoleredwa kuti muchepetse kusokonekera, ntchito zachiwirizo zimakhala zokwera mtengo, zomwe zimawononga ndalama zoyambira. Ndagwirapo ntchito ndi anzanga omwe amamvetsetsa bwino kuphatikiza uku. Mwachitsanzo, Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), ndi zaka makumi akuponya ndi makina, amamvetsa kusintha kumeneku pakati pa njira mwachidwi. Ngakhale maziko awo ali mu chipolopolo cha chipolopolo ndi kupanga ndalama, mfundo zoyendetsera khalidwe lachinthu ndi makina olondola achiwiri amasamutsidwa mwachindunji. Mukayendera malo ngati awo, mumawona makina a CNC okonzeka kutsiriza mbali zooneka ngati ukonde, kaya zimachokera ku nkhungu yoponyera kapena PM compact. Kuthekera kotsikirako kumatengera momwe mumayendetsera njira yakumtunda kwa PM.
Ponena za ma ops achiwiri, chithandizo cha kutentha pambuyo pa sintering ndi dziko lakelo. Kuumitsa gawo la PM sikuli ngati kuumitsa chitsulo chopangidwa. The porosity imagwira ntchito ngati maukonde ang'onoang'ono olimbikitsira. Ngati simusamala ndi momwe ma carburizing amakhalira komanso kuchuluka kwa kuzimitsa, mutha kulimbikitsa makutidwe am'malire a tirigu m'mphepete mwa pore, ndikupangitsa gawolo kukhala lolimba. Taphunzira izi movutikira pagulu la zida zopatsirana. Anadutsa macheke a kuuma koma anayamba kusweka pansi pa torque. Kusanthula kulephera kunalozera ku intergranular oxidation iyi. Kukonza? Kutentha kosinthika kokhala ndi kuwongolera kolimba kwambiri munthawi yakukula kwamphamvu. Zinawonjezera mtengo ndi nthawi, koma zinali zimenezo kapena kuchotseratu ntchito yonse.
Nthawi zina, yankho silikhala njira yochulukirapo, koma kusintha kwazinthu. Tinali ndi pulojekiti yopangira gawo lovala kwambiri pamakina opangira chakudya. Chitsulo cholimba cha PM sichinakhazikike. Tinkayang'ana kulowerera ndi mkuwa, koma zinthu zovuta. Kenako tinayamba kugwiritsa ntchito ufa wosakanizidwa womwe umatha kukhala ndi mafuta olimba, ngati kuchuluka kwa graphite, komwe kumalowetsedwa mu matrix. Icho chinapanga khalidwe lodzipaka mafuta lomwe linawonjezera kwambiri moyo wautumiki. Sinali buku loyamba kusankha, koma zidabwera chifukwa chomvetsetsa kuti ntchitoyo - kuchepetsa kukangana ndi kukwiya - inali yofunika kwambiri kuposa kuthamangitsa mphamvu zolimba.
The Tooling Grind ndi Prototype Hurdles
Palibe chomwe chimabweretsa chiphunzitso padziko lapansi ngati chida. Kupanga ndi kukonza seti ya die ndi pomwe lingaliro la gawo limakhala lenileni. Kuchotsera kumayezedwa mu magawo zikwi khumi a inchi. Kusokonekera pang'ono pamalumikizidwe a ndodo yapakati, ndipo mumayamba kutha mbali imodzi, zomwe zimapangitsa kuti pakhale vuto la kutulutsa ndi kulephera kwa zida mwachangu. Mtengo ndi nthawi yotsogolera yogwiritsira ntchito zida ndiye zopinga zazikulu pakupanga ma prototyping mu PM. Sizili ngati makina pomwe mumangokonzanso njira. Izi zimapangitsa kuti azimitsidwa mwadongosolo kwambiri. Ndikukumbukira fanizo lomwe limayendetsa nyumba ya sensa komwe kasitomala amangokhalira kusuntha malo okwera. Pambuyo pa kusinthidwa kwachitatu kwa zida, mtengo wake unaposa ndalama zonse zomwe zidasungidwa mchaka choyamba. Tidayenera kukankhira mmbuyo ndikumaliza mapangidwewo, kufotokoza kuti kulimba mtima kwa PM kumabwera pambuyo poti zida zatsimikiziridwa, osati panthawi yomwe idapangidwa.
Chotchinga chachikulu ichi cholowera ma prototypes ndichifukwa chake ambiri amayang'ana makampani omwe ali ndi kuthekera kofananira. Ngati chigawocho sichikugwira ntchito bwino, chingakhale chanzeru kuchifanizira kudzera munjira yosinthika monga kuyika ndalama kapena makina a CNC kuchokera ku bar stock kuti atsimikizire mawonekedwe, kukwanira, ndi magwiridwe antchito. Mapangidwewo akatsekedwa, ndiye kuti mumagulitsa zida za PM kuti mupange voliyumu. Kampani ngati QSY, ikugwira ntchito m'njira zingapo (https://www.tsingtaocnc.com), ali ndi udindo wolangiza paulendo womwewu. Amatha kuthana ndi mawonekedwewo kudzera m'masitolo awo opangira zinthu kapena CNC, kenako ndikusintha mapangidwe okhwima kukhala PM kuti azitha kupanga, ndikusunga kusasinthika kwazinthu zakuthupi ndi makulidwe ofunikira kudzera m'makina awo amkati.
Kuvala zida sizochitika zofananira; ndikuwonongeka kwapang'onopang'ono komwe kumasintha mochenjera gawolo. Mutha kuyamba kupanga zida pamwamba pa gulu la tolerance, ndipo makina osindikizira oposa 100,000, amasunthika mpaka pansi. Njira yabwino imaphatikizapo kufufuza ndi kukonza zida, koma mumaphunziranso zizindikiro-kuwonjezeka pang'ono kwa mphamvu ya ejection, burr yaying'ono pamphepete mwapadera. Kuchigwira ndiye kupulumutsa phiri la kusanja ndi zidutswa pambuyo pake.
Atmosphere and Sintering: The Invisible Hand
Mng'anjo yotentha ndiye mtima wa opareshoni, ndipo mlengalenga ndi moyo wake. Kuthamanga 90/10 nitrogen-hydrogen mix ndi muyezo, koma chiyero ndi nkhani. Kuchuluka kwa okosijeni kapena chinyezi, ndipo mukukwera ngalawa zambiri. Tidayika makina owunikira nthawi yeniyeni titataya kupanga kwa tsiku lonse ku botolo la gasi loyipa. Zambirizi zinali zotsegula m'maso - mumatha kuwona mame akuwomba mphindi zingapo zisanawonekere vuto lililonse. Tsopano ndi gawo lomwe silingakambirane pakukhazikitsa.
Sintering kutentha ndi nthawi ndi kuvina. Mabuku amakupatsirani mitundu, kunena kuti 1120 ° C kwa mphindi 30 pachitsulo china. Koma ng'anjo yanu yotentha, gawo lanu lodzaza kachulukidwe pa lamba, ngakhale chinyezi chozungulira chomwe chimakhudza magawo obiriwira akamalowa - zonse zimasintha malo abwinowo. Mumapanga njira yopangira gawo lililonse la banja, koma nthawi zonse mumasintha. Kodi liwiro la lamba ndikugwira mwachangu kwambiri? Kodi zigawo zapakati pa lamba zimafika kutentha? Mumaphunzira kuwerenga mtundu wa sintered ndi mphete ya gawo lojambulidwa patebulo momwe mumawerengera pyrometer.
Mlingo wozizira ndi chinthu chomwe sichikambidwanso. Kuziziritsa mwachangu kumatha kutulutsa zitseko mwachangu, koma kwa ma aloyi ena, kumatha kutsekereza kupsinjika kapena kulepheretsa kupangika kwathunthu kwa magawo ofunikira azitsulo. Nthawi zina mumafunika kuziziritsa kozizira, komwe kumalepheretsa kutulutsa kwang'anjo. Ndi kupanga tingachipeze powerenga vs. khalidwe malonda-kuchoka kuti amathetsedwa osati ndi buku, koma ndi ntchito gawo m'munda. Ngati mbali zikubwerera ndi micro-ming'alu, malo oyamba kuyang'ana ndi malo ozizira.
Kuganiza Mopitirira Atolankhani
Pamapeto pake, kupambana mu powder metallurgy ndikuwona gawolo ngati dongosolo mkati mwa dongosolo. Sichigawo chapadera. Kodi zimalumikizana bwanji ndi shaft? Kodi ndizokwanira, ndipo ngati ndi choncho, porosity imakhudza bwanji kuwerengera kosokoneza? Tidakhala ndi vuto pomwe chitsamba chowoneka bwino cha PM chidasweka pa msonkhano wa atolankhani. Vuto silinali tchire; chinali chotengera cholimba chonyamulira chonyamulidwa kuchokera pamapangidwe opangidwa. Tidayenera kuwerengeranso zoyenera kutengera kulimba kwenikweni kwa zinthu zaporous, osati kachulukidwe ake olimba.
Kawonedwe kadongosolo kameneka ndi komwe kamalekanitsa wogulitsa magawo ndi mnzake wopanga. Ndiko kufunsa kuti, Kodi gawoli liyenera kuchita chiyani? osati chabe, Kodi tingapange mawonekedwe awa? Zimakhudzanso kumvetsetsa njira zonse zogulitsira, kuyambira pakufufuza ufa (kumene kusasinthasintha kumakhala koyenera) mpaka kuperekera komaliza. Ichi ndichifukwa chake opanga omwe akhalapo nthawi yayitali, kaya amayang'ana kwambiri pa PM, kuponyera, kapena kupanga makina, nthawi zambiri amakhala ndi chidziwitso chozama kwambiri. Iwo awona zolephera, amayendetsa kusowa kwa zinthu, ndikusintha njira kuti mizere igwire ntchito. Zomwe zinachitikira, mtundu womwe unamangidwa zaka 30 monga tafotokozera mu machitidwe a QSY kudutsa kuponyera ndi kupanga makina, amadziwitsa sitepe iliyonse-kuyambira kusankha zinthu ndi ndondomeko ya ndondomeko mpaka kuwunika komaliza-kuwonetsetsa kuti gawolo silimangosindikiza, koma limapulumuka mu dziko lenileni.
Kotero, pamene ine ndikuganiza za ntchito mu powder metallurgy, ndi zochepa za ndondomeko buku ndi zambiri za kusanjikiza anasonkhanitsa kusintha zothandiza. Ndi gawo lomwe nthawi zonse mumayang'anira mafiziki abwino ndi zenizeni zazachuma zopanga komanso zovuta zakuthupi. Ufa ndi poyambira chabe.
