Uyazi, lapho abantu abangaphandle kohwebo bezwa 'i-powder metallurgy', bavame ukugxumela baqonde ekucindezeleni—ukuhlanganiswa kwaleyo mpushana ecolekileyo, eyomile ibe ingxenye eyaziwayo 'eluhlaza'. Yilokho okuncane okubonakalayo. Kodwa i-alchemy yangempela, lapho umphefumulo wezinto ezibonakalayo unqunywa khona ngempela, kwenzeka esithandweni ngesikhathi ukucula. Itemu elilula elikhohlisayo lenqubo egcwele ukuhluka. Yenza iphutha, futhi awubheki nje ingxenye ebuthakathaka; ubheka i-scrap edlule ezinyathelweni ezimbalwa ezibizayo ukuze wehluleke ekugcineni, isithiyo esishisayo. Akukhona nje 'ukuyishisisa'; umdanso olawulwayo wokusabalalisa, ukwakheka kwentamo, nokuzungeza kwezimbotshana, konke kulenga ekuphathweni okunembile kwesikhathi, izinga lokushisa, nomoya.
I-Atmosphere Akuyona Nje Igesi Yasemuva
Ekuqaleni, ngafunda lokhu kabuhlungu. Sasinenqwaba yamaflange ensimbi ene-alloy, ecindezelwe kahle. Umjikelezo wesithando somlilo wawusethwe kusukela kuresiphi evamile evamile. Kodwa ukulawulwa komkhathi kwakunosuku olungasebenzi—ukushintshashintsha kancane kwegesi ye-endothermic, indawo yamazolo engaphezulu kunokufanelekile. Umphumela? I-Decarburization ebusweni ebusweni obuthwala umthwalo obalulekile. Izingxenye zibukeka zilungile, zadlula ukubuka okuvamile, kodwa ngaphansi kokuhlolwa kokuqina okuncane, zabonisa isikhumba esithambile. Ayinamsebenzi kuhlelo lokusebenza. Kungaleso sikhathi lapho eyachofoza khona: umkhathi we-sintering awuyona indawo yokungenzi lutho; ungumhlanganyeli osebenzayo. Okwezinsimbi, kumayelana nokugcina amandla ekhabhoni. Ngokungenasici, imayelana nokuvimbela ukwakheka kwe-chromium oxide, okungase kusho ukuhlanzeka okuphezulu kwe-hydrogen noma i-vacuum run. Ngikhumbula ngithola iqoqo elikhethekile legesi kumhlinzeki esimethembayo, futhi umehluko engxenyeni yokugcina engaguquguquki wawubusuku nemini.
Lokhu kuhlotshaniswa nezinto esivame ukuziphatha. Kwa-QSY, ngesizinda sethu sokutshala izimali kanye nokwenza ama-alloys akhethekile afana nalawo asekelwe ku-nickel, ingqondo iyafana kodwa ukusebenza kuyehluka. Ukusakaza kusebenzisana nokugeleza kwensimbi encibilikisiwe; i-powder metallurgy sintering ibhekene nokusatshalaliswa kwesimo esiqinile. Kodwa ulwazi lwezinto ezibonakalayo luyawela. Uma iklayenti liza nesicelo sengxenye ye-cobalt-chromium edinga ukumelana nokugqokwa okuphezulu, siyazi ngokuhlangenwe nakho kwethu kokusakaza ukuthi lawa ma-alloys azwela kangakanani kumlando oshisayo. Ukuhumushela lokho kumzila we-PM kusho ukuqonda ukuthi izinga lokushisa le-sintering ku-alloy enjalo aliyona iphuzu elilodwa kodwa iwindi elincane—liphansi kakhulu, futhi ukuminyana kuyaphazamiseka; phezulu kakhulu, futhi usengozini yokukhula okusanhlamvu ngokweqile noma ukwakheka kwesigaba soketshezi okuhlanekezela ingxenye. Iphrofayili yesithando somlilo iba bucayi.
Awukwazi ukukhuluma nge-atmosphere ngaphandle kokuthinta ama-vacuum furnaces. Ziyi-godsend yezinto ezisebenzayo. Senze ezinye izivivinyo nge-316L yempushana engagqwali. Emkhathini we-hydrogen, ungathola imiphumela emihle, kodwa i-vacuum sintering? Ikhiqize izingxenye ezinemingcele ehlanzekile yokusanhlamvu kanye nokumelana nokugqwala okuphakeme, okubalulekile kwezinye zezinto zasolwandle esibuzwe ngazo. Okubi yizindleko nesikhathi somjikelezo. Ukuhlola njalo kokuhwebelana: ingabe ukuzuza kokusebenza kuyavumelana nezindleko zokukhiqiza? Leso isibalo somhlaba wangempela esisenza nsuku zonke, hhayi nje umbuzo wencwadi yokufunda.
Izinga lokushisa nesikhathi: Kuyiphrofayela, Akusona Isilungiselelo
Omunye umgodi ovamile ukuphatha izinga lokushisa le-sintering njengenombolo eyodwa oyisethayo futhi oyibambayo. Eqinisweni, izinga lokukhuphuka, izikhathi zokucwiliswa emazingeni okushisa aphakathi nendawo (njengokushiswa kwe-binder ezingxenyeni ezibunjwe ngomjovo oyimpushana), kanye nezinga lokupholisa konke kuyingxenye 'yephrofayela'. Ngikhumbula iphrojekthi yegiya eliyinkimbinkimbi lapho sabhekana khona nokuqhekeka ngesikhathi sokupholisa. Umlandu? Ukupholisa okushesha kakhulu kusuka kuzinga lokushisa elishisayo. I-gradient eshisayo idale ingcindezi i-microstructure esahlanganisayo ayikwazanga ukuyiphatha. Kudingeke ukuthi silungise uhlelo lwesithando somlilo ukuze sifake indawo elawulwayo epholile kancane. Yengeze amahora kumjikelezo kodwa yalondoloza yonke inqwaba.
Yilapho umuzwa ongokoqobo ungena khona. Izincwadi zokufunda zikunikeza imidwebo yesigaba kanye namajika okuminyana kwethiyori. Kodwa phansi esitolo, ubheke izimpawu. Umbala wezingxenye eziphumayo, umsindo eziwenzayo lapho uchofozwa kancane (i-thud efiphele ngokumelene nendandatho epholile), ngisho nendlela abahlala ngayo kuthreyi ye-sintering-warpage iyisipho esifile sokushisisa okungalingani noma ukusekelwa okubi phakathi nomjikelezo oshisayo. Yilawa masheke wekhwalithi, alolongwa ngokuhamba kwesikhathi, abamba izinkinga ngaphambi kokuthi i-CMM noma umhloli we-tensile enze.
Ukuxhumanisa lokhu emuva emandleni ethu ahlanganisiwe ku I-Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), Isinyathelo se-sintering akusona isiqhingi. Ingxenye ingase iphume esithandweni ngo-95% wokuminyana kwethiyori. Ezinhlelweni eziningi, lokho kulungile. Kodwa ngomzimba we-hydraulic valve odinga ukuqina kokuvuza okuphelele, ungadinga ukuhlinzwa kwesibili njengokufakwa kwe-resin. Noma, ingase iqonde ngqo kumaseli ethu omshini we-CNC ukuze aqedele usayizi obalulekile—ukubhoboza izimbobo ezinembile, ukuhlanganisa, ukudala izindawo zokuvala. Iqiniso lokuthi silawula kokubili inqubo ye-sintering kanye nokukhanda okulandelayo ngaphansi kophahla olulodwa kusho ukuthi siyaqonda ukuthi i-sintered microstructure iziphatha kanjani ngesikhathi sokusika. Ingxenye ene-sintered kabi ingaba ne-abrasive futhi ihlafune ngokusebenzisa amathuluzi; imishini efakwe kahle ihlanzekile. Leyo ndlela yempendulo phakathi kwesitolo somlilo kanye nesikhungo somshini ibaluleke kakhulu.
Ifa Lengxenye Eluhlaza
Konke ku-sintering kunqunywa kusengaphambili isimo se-compact eluhlaza. Ukuminyana kusukela ekucindezelweni, noma yimaphi amaphutha okukhanyisa, ukufana kokusatshalaliswa kwempushana—lokhu akuphiliswa esithandweni; bayakhuliswa. Ukwehluka okuncane kokuminyana kungaholela ekuncipheni okuhlukile, kuphendule iphutha elincane lokucindezela libe ukulahlwa kwe-post-sinter ye-dimensional enkulu. Sake saba nezinkinga ngephini elide, elincanyana. Babelokhu bephuma begobile. Ngemuva kokujaha amaphrofayili esithandweni somlilo, ekugcineni sabheka emuva ekusetshenzisweni kwamathuluzi. Ukungaqondani kahle okuncane emaphephandabeni bekubangela ukugcwaliswa kwempushana okungalingani futhi, ngenxa yalokho, ukuminyana okuluhlaza okungalingani. Lungisa umshini wokunyathelisa, lungisa ingxenye ye-sintered. Isifundo: Ukucula kuvame ukusolwa ngezinkinga ezizalwe ngaphambi kwesikhathi kakhulu ohlelweni lwenqubo.
Lokhu kuyiqiniso ikakhulukazi kumajamo ayinkimbinkimbi. Ekwenziweni kokutshalwa kwezimali, okungenye ikhono eliyinhloko le-QSY, isikhunta sichaza umumo. Ku-PM, i-die ichaza ekuqaleni, kodwa ingxenye iyancipha ngenkathi i-sintering-futhi ayihlali incipha ngokwe-isotropically. Ukuklama ithuluzi kudinga ukulindela lokhu kuncipha kwe-anisotropic, okuvela endaweni ecindezelayo kanye nokuma kwezinhlayiyana. Iwubuciko obunamandla njengesayensi. Sinemitapo yolwazi yezinto ezinciphayo zezinto ezihlukene kanye nengxenye yejometri, eyakhiwe ngokuhamba kweminyaka, eqondisa ukwakhiwa kwamathuluzi ethu. Ngeke uthole lezo zinombolo ngqo encwadini yesandla.
Lapho Izinto Zingahambi Kahle
Ukwehluleka okuyinhlekelele—ukuncibilika, ukuhlanekezela okukhulu—kusobala. Okukhohlisayo yiziphambeko ezicashile. Ukuncibilika kokuqala emingceleni yokusanhlamvu ngoba ugudluze eduze kakhulu komugqa we-solidus. Ukuqunjelwa ngokweqile kuholela ekuqunjelweni, lapho izimbotshana ezivaliwe zigcwala igesi evaleleke. Noma i-sintering engaphansi, ishiya ingxenye inamandla anganele, iphutha elingase livele ekuhlolweni kokukhathala isikhathi eside ngemva kokuthunyelwa. Ngiqaphela ikakhulukazi ama-alloys. Umsebenzi wethu ngama-alloys akhethekile ekubumbeni usinika inhlonipho enempilo yokuzinza kwesigaba sabo. Ukusebenzisa lokho ku-PM, ukufaka ingxenye ye-nickel-based superalloy akukhona nje ukuzuza ukuminyana; imayelana nokuqinisekisa ukwakheka kwemvula ye-gamma prime okulungile ngesikhathi sokupholisa, ebeka ukusebenza kwayo kwezinga lokushisa eliphezulu. Lokho kudinga ukwelashwa okukhethekile kwangemuva kwe-sinter, okuvame ukuhlanganiswa kumjikelezo wokupholisa wesithando somlilo ngokwaso.
Ukulawulwa kwekhwalithi ngemuva kwe-sinter akukhona nje ukuhlola kobukhulu. I-metallography. Ukusika ingxenye kumthwalo ngamunye wesithando somlilo, ukukhwezwa, ukupholishwa, nokuwunamathisela ukuze ubuke ukwakheka kwezimbotshana kanye nosayizi wokusanhlamvu. Ingabe izimbotshana ziyindilinga futhi zihlukanisiwe (zinhle) noma zixhumene (zimbi)? Ingabe ukwakheka okusanhlamvu kukhule ngokweqile? Lokhu kuhlaziya okwenziwa ngesandla akuxoxiswana ngakho. Yikhadi lokugcina lombiko wenqubo yokucula. Ngezinye izikhathi, ubona okuthile okungalindelekile—njengokufakwa kwe-oxide kumpushana engcolile—futhi uphenyo kufanele lulandelele emuva ngisho nangaphambi kokucindezela.
Sintering njengesango leValue
Ekugcineni, endaweni yokuncintisana, inqubo ye-sintering iyisango elikhulu lokwengeza inani-noma ukulahlekelwa yilo. Ungaba nempushana elungile, ukucindezela okuphelele, kodwa ukucwilisa okuphakathi, bese ugcina usunomkhiqizo omaphakathi. Ngokuphambene, ukuba yingcweti kwe-sintering kungavula amandla aphelele wezinto ezibonakalayo, okukuvumela ukuthi unikeze izakhiwo ezincintisanayo ezikhangiwe noma ezisakazwayo, kodwa ngezinzuzo zezomnotho ezinomumo wenetha we-PM. Enkampanini efana ne-QSY, ehlanganisa ukulingisa, ukukhanda, nokusebenzisana nezinqubo ze-PM, umbono uphelele. Asikuboni ukucula njengesinyathelo sokushisa esodwa, kodwa njengomcimbi oqondile wokudala i-microstructural ochungechungeni lwe-PM. Kulapho izinhlayiya zempushana ziyeka khona ukuba abantu ngabanye futhi zibe izinto zobunjiniyela ezihlangene, ezisebenzayo. Ukuyilungisa yikho okuhlukanisa izingxenye ezikhona ezingxenyeni ezisebenza ngokwethembeka ensimini. Futhi lokho, ekugcineni, yilokho okushiwo ukukhiqiza.
