Munoziva, kana vanhu vari kunze kwekutengesa vachinzwa 'powder metallurgy', vanowanzosvetukira vakananga kudhindindiro - kubatanidzwa kwehupfu hwakatsetseka, hwakaoma kuita chikamu chinozikanwa 'chegirini'. Ndiwo chidimbu chinoonekwa. Asi iyo chaiyo alchemy, apo mweya wezvinhu unosarudzwa zvechokwadi, unoitika muchoto panguva sintering. Iri izwi rinonyengera rakareruka kune maitiro akazara ne nuance. Ita zvisizvo, uye hausi kungotarisa chikamu chisina simba; uri kutarisa zvimedu zvakapfuura nematanho akati wandei anodhura chete kuti zvikundikane pakupedzisira, kupisa kwehurdle. Hakusi chete 'kuchipisa'; Kutamba kunodzorwa kwekupararira, kuumbwa kwemutsipa, uye kutenderedzwa kwepore, zvese zvakarembera pakurongeka chaiko kwenguva, tembiricha, nemhepo.
Iyo Atmosphere Haisi Ingori Yekumashure Gasi
Pakutanga, ndakadzidza izvi nenzira yakaoma. Takanga tine batch ye low-alloy steel flanges, yakatsikirirwa zvakaisvonaka. Kutenderera kwechoto kwakaiswa kubva kune yekare chiyero resipi. Asi kudzora kwemhepo kwakange kuine zuva rekuzorora-kushanduka kudiki mukugadzirwa kwegasi rekupedzisira, dova rakawedzera pane kunaka. Zvakaguma nei? Surface decarburization pane dzakakomba dzinotakura zviso. Zvikamu zvaitaridzika zvakanaka, zvakapfuura chitarisiko, asi pasi pekuyedzwa kwe microhardness, vairatidza ganda rakapfava. Hazvibatsiri pakushandisa. Ndipo payakadzvanya: mhepo inoyerera haisi nharaunda inongogara; mutori wechikamu anoshingaira. Zvesimbi, ndezvekuchengetedza kabhoni. Kune isina tsvina, ndeye kudzivirira chromium oxide kuumbwa, izvo zvinogona kureva yakakwirira-kuchena hydrogen kana vacuum run. Ndinorangarira ndichitsvaga bhechi regasi kubva kune mupi wataivimba naye, uye mutsauko muchikamu chekupedzisira chaive husiku nemasikati.
Izvi zvinosungirirana nezvinhu zvatinowanzobata. PaQSY, nekwatakabva mukudyara kwekudyara uye kugadzira alloys akakosha senge nickel-based, pfungwa dzakafanana asi kuuraya kunosiyana. Kukandira kunobata nekuyerera kwesimbi yakanyunguduka; upfu metallurgy sintering inobata neiyo solid-state diffusion. Asi ruzivo rwezvinhu runodarika. Kana mutengi achiuya nechikumbiro checobalt-chromium chikamu chinoda kupfeka kwakanyanya kuramba, isu tinoziva kubva muchiitiko chedu chekukanda kuti maalloys aya ane hanya sei kune nhoroondo yekupisa. Kuturikira izvozvo kuPM nzira kunoreva kunzwisisa kuti sintering tembiricha yealloy yakadaro haisi imwe poindi asi hwindo nhete-yakanyanya kuderera, uye density inotambura; yakakwira zvakanyanya, uye unoisa panjodzi yekukura kwezviyo zvakanyanya kana kunyange kuumbwa kwechikamu chemvura chinokanganisa chikamu. Iyo mbiri yevira inova yakakosha.
Iwe haugone kutaura mamiriro ekunze usina kubata pavacuum furnaces. Ndivo godsend nokuda reactive zvinhu. Takamhanyisa mimwe miedzo ne 316L stainless poda compacts. Mumhepo yehydrogen, unogona kuwana mhedzisiro yakanaka, asi vacuum sintering? Yakagadzira zvikamu zvine miganhu yezviyo zvakachena uye nepamusoro-soro kudzivirira kukora, yakakosha kune zvimwe zvemugungwa zvatakabvunzwa nezvazvo. Iyo yakaderera ndiyo mutengo uye kutenderera nguva. Iyo inogara ichitengeserana-yekudzokorodza kuongororwa: kuita kunowanikwa kunopembedza mutengo wekugadzira? Ndiko kuverenga kwepasirese kwatinoita zuva nezuva, kwete mubvunzo webhuku.
Tembiricha uye Nguva: Inhoroondo, Kwete Kugadzika
Imwe gomba rinowanzoitika kubata tembiricha ye sintering senhamba imwechete yaunoseta nekubata. Muchokwadi, chiyero chekukwira, nguva dzekunyorova patembiricha yepakati (senge yebhainda kupiswa muzvikamu zvakaumbwa jekiseni reupfu), uye mwero wekutonhora zvese chikamu che'profile'. Ndinoyeuka purojekiti yegiya rakaomarara kwatakasangana nekutsemuka panguva yekutonhora. Mupari wemhosva? Kukurumidza kutonhora kubva kune sintering tembiricha. Iwo anopisa magradients akakurudzira kushushikana kuti ichiri-inobatanidza microstructure haigone kubata. Taifanira kugadzirisa purogiramu yevira kuti ibatanidze nzvimbo inodzorwa inononoka-inotonhorera. Yakawedzera maawa kutenderera asi yakachengetedza batch rese.
Apa ndipo panouya manzwiro anoshanda. Mabhuku ekuverenga anokupa madhiyagiramu echikamu uye theoretical density curves. Asi pauriri hwechitoro, uri kutarisa zviratidzo. Rudzi rwezvikamu zvinobuda, ruzha rwavanoita kana rwakabatwa zvishoma (kutinhira kunopesana nemhete isina simba), kunyange nzira yavanogara pane sintering tray-warpage ndiyo yakafa inopa kupisa kusina kuenzana kana kutsigirwa kusina kunaka panguva yekupisa. Aya macheki emhando, anokudzwa nekufamba kwenguva, anobata matambudziko pamberi peCMM kana tensile tester.
Kubatanidza izvi kumashure kune edu akabatanidzwa kugona pa Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), nhanho yekunyura haisi chitsuwa. Chikamu chinogona kubuda muchoto chiri pa95% theoretical density. Kune akawanda maapplication, zvakanaka. Asi kune hydraulic valve body inoda kunyuza-kusimba, ingangoda oparesheni yechipiri senge resin impregnation. Kana, inogona kuenda yakananga kune yedu CNC machining maseru ekupedzisa kweakakosha zviyero-kuchera maburi chaiwo, shinda, kugadzira nzvimbo dzekuisa chisimbiso. Icho chokwadi chekuti isu tinogadzirisa zvese sintering maitiro uye inotevera machining pasi pedenga rimwe zvinoreva kuti tinonzwisisa maitiro ayo sintered microstructure maitiro panguva yekucheka. Chikamu chisina kucheneswa chinogona kuve chinokanganisa uye kutsenga kuburikidza nemidziyo; anonyatso sintered imwe michina yakachena. Iyo yemhinduro loop pakati pechoto shopu uye machining centre yakakosha.
Nhaka yeGreen Chikamu
Zvese mu sintering zvakafanotemerwa nemamiriro egirinhi compact. Density gradient kubva mukutsikirira, chero kukanganisa kwemwenje, kufanana kwekugovaniswa kweupfu - izvi hazvipore muchoto; vanowedzerwa. Musiyano mudiki density unogona kutungamira mukudonha kwemutsauko, kushandura diki kudzvanya chikanganiso kuita huru dimensional kurambwa post-sinter. Takamboita nyaya nepini refu, nhete. Vakaramba vachibuda vakakotama. Mushure mekudzingirira ma profiles echoto, isu takazotarisa kumashure kune tooling. Kusarongeka kudiki mumuchina kwaikonzera kuti hupfu husina kuenzana huzadze uye, nekudaro, hunyoro hwegirini husina kuenzana. Gadzirisa kudhinda, gadzirisa sintered chikamu. Chidzidzo: sintering inowanzopomerwa mhosva yezvinetso zvakazvarwa kare kare mucheni yekuita.
Izvi ndezvechokwadi kunyanya kune zvimiro zvakaoma. Mukudyara kwekudyara, inova imwe QSY yakakosha kugona, mold inotsanangura chimiro. MuPM, iyo inofa inoitsanangura pakutanga, asi chikamu chinodzikira panguva yekunyura-uye haigare ichiderera isotropically. Kugadzira iyo yekushandisa kunoda kutarisira iyi anisotropic shrinkage, iyo inouya kubva kune yekutsikirira nzira uye particle orientation. Inyanzvi yehunyanzvi sesainzi. Tine maraibhurari e shrinkage zvinhu zvezvinhu zvakasiyana uye chikamu geometries, yakavakwa nekufamba kwemakore, inotungamira dhizaini yedu yekushandisa. Hauzowani nhamba idzodzo mubhuku rekushandisa.
Kana Zvinhu Zvichinyanya Kushata
Kukundikana kune ngwavaira—kunyunguduka, kumonyaniswa kukuru—zviri pachena. Iwo anonyengera ndiwo zvikanganiso zvisingaoneki. Kutanga kunyunguduka pamiganhu yezviyo nekuti wakasvebera pedyo zvakanyanya netambo ye solidus. Over-sintering inotungamira mukuzvimba, uko mapores akavharika anozvimba negasi rakavharirwa. Kana kuti pasi-sintering, ichisiya chikamu chisina simba rakakwana, chikanganiso chinogona kungo ratidza mukuneta kuyedza nguva refu mushure mekutumirwa. Ndiri kunyanya kungwarira nealloys. Basa redu rine alloys akakosha mukukanda rinotipa ruremekedzo rune hutano hwekugadzikana kwechikamu chavo. Kushandisa izvozvo kuna PM, sintering nickel-based superalloy component hakusi kwekungoita density; ndezvekuona iyo chaiyo gamma prime precipitate kuumbwa panguva yekutonhora, iyo inoraira kuita kwayo kwepamusoro-tembiricha. Izvo zvinoda chaiyo chaiyo post-sinter kupisa kurapwa, kazhinji kubatanidzwa mukutonhora kutenderera kwechoto pachako.
Kudzora kwemhando post-sinter hakusi kungotarisa mativi. Zviri metallography. Kucheka chikamu kubva muchoto chega chega mutoro, kukwira, kupukuta, uye kuchiisa kuti utarise chimiro chepore uye saizi yezviyo. Mapores akatenderedzwa uye akaparadzaniswa (akanaka) kana akabatana (akaipa)? Chimiro chezviyo chakura zvakanyanya here? Iyi ongororo yemaoko haigone kutaurirana. Ndiyo yekupedzisira report card ye sintering process. Dzimwe nguva, iwe unoona chimwe chinhu chisingatarisirwi-senge oxide inclusions kubva muhupfu hwakasvibiswa-uye tsvakiridzo inofanirwa kutsvaga kumashure kunyangwe isati yadzvanya.
Sintering as A Value Gate
Pakupedzisira, munzvimbo yemakwikwi, iyo sintering ndiyo gedhi guru rekuwedzera kukosha-kana kurasikirwa nayo. Iwe unogona kuve nehupfu hwakakwana, kudzvanya kwakaringana, asi mediocre sintering, uye unozopedzisira wava nechigadzirwa chepakati. Sezvineiwo, mastering sintering inogona kuvhura iyo yakazara mukana wezvinhu, zvichikubvumidza iwe kupa zvivakwa zvinokwikwidza kugadzirwa kana kukanda zvinhu, asi nemambure-chimiro chehupfumi mabhenefiti ePM. Kune kambani yakaita seQSY, iyo inotambanudzira kukanda, kugadzira, uye kuita nePM maitiro, maonero akazara. Isu tinoona sintering kwete senge yakasarudzika yekupisa nhanho, asi seyakajeka microstructural kugadzirwa chiitiko muPM ketani. Ndiko uko hupfu hwehupfu hunomira kuve vanhu uye huve hwakabatana, hunoshanda huinjiniya zvinhu. Kuzvigadzirisa ndiko kunopatsanura zvikamu zvinongovepo kubva kune zvinoita zvakavimbika mumunda. Uye izvo, pakupedzisira, ndizvo zvinogadzirwa nekugadzira.
