Lokacin da kuka ji 'kayan gyare-gyaren allurar ƙarfe', yawancin hankali suna tsalle kai tsaye zuwa foda na ƙarfe. Wannan shine aikin kanun labarai, tabbas. Amma idan kun yi amfani da kowane lokaci a filin shago, kun san ainihin labarin yana farawa da tsarin ɗaure kuma ya ƙare da yanayin tanderun. Yana da dukan hadaddiyar giyar da ke da mahimmanci, ba kawai ruhu ba. Na ga ayyuka da yawa sun tsaya tsayin daka saboda wani ya samo kyakkyawan foda mai siffar zobe 17-4PH amma ya haɗa shi tare da abin ɗaure kakin zuma-polymer wanda ba zai iya sarrafa juzu'i na ɓangaren ba, wanda ke haifar da ɓarna mai haɗari yayin ƙaddamarwa. Kayan ba kawai karfe ba ne; kayan abinci ne. Wannan shine darasi na farko, kuma galibi mafi tsada.
Ma'aunin Ciyarwa: Fiye da Fasaha Fiye da Kimiyya
Samun kayan abinci daidai yana jin kamar alchemy wani lokaci. Madaidaicin rabon ɗora foda — wannan adadin ƙarar foda a cikin ɗaure - tafiya ce ta igiya. Matsa shi sama da ƙasa don haɗaɗɗiyar sashe, kuma kuna rasa madaidaicin iya tafiyar da MIM ke da daraja. Injin gyare-gyaren allura yana fama, kuna samun layukan weld, babu komai. Ya yi ƙasa da ƙasa, kuma ɓangaren yana raguwa ba tare da annabta ba yayin sintering, yana ƙarewa ba tare da ƙayyadadden bayani ba. Don babban kayan sawa mun taɓa gudu, ta amfani da lafiyayyen foda 316L mai iskar gas, dole ne mu buga lodin ƙasa kaɗan daga shawarwarin littafin. Me yasa? Bangaren yana da sashin giciye mai ban dariya na ban dariya kusa da wata cibiya mai kauri. Daidaitaccen lodi ya haifar da alamun nutsewa. Mun yi sulhu a kan ƙaramin ɗan ƙaramin ƙima don tabbatar da cikawa, sannan mu tweaked bayanin martaba don ramawa. Ya yi aiki, amma ba a cikin kowane littafin.
Anan ne aka yi watsi da aikin mai ɗaure da laifi. Ba manne na ɗan lokaci ba ne kawai. Rarraba motsin motsinsa a lokacin daɗaɗɗen zafi ko sauran ƙarfi dole ne a daidaita shi daidai tare da tattarawar foda. Rashin daidaituwa a nan, kuma za ku sami kumburi, tsagewa, ko 'bangaren kore' ya rushe. Na tuna wani tsari inda mai ɗaure ya canza mai ƙara kuzari ba tare da sanarwa ba. Sassan sun yi kama da kamala suna fitowa daga cikin kwandon, amma a cikin tanderun debind, sun faɗi kamar gaji kullu. Jimillar hasara. Foda ya kasance iri ɗaya, ƙayyadaddun ƙarfe bai canza ba. Rashin nasarar ya kasance a cikin 'kananan' ɓangaren tsarin ɗaure.
Kuma bari muyi magana game da halayen foda. Sphericity da rarraba girman barbashi (PSD) sune komai. Ƙaƙƙarfan PSD na iya ba da babban ka'idar tattara kaya, amma sarrafawa mai kyau, ɗimbin rarrabuwa mafi fa'ida sau da yawa yana gudana mafi kyau a aikace kuma masu sintiri cikin dogaro. Don kayan abinci na likitanci na cobalt-chrome, mun yi yaƙi da matsalolin porosity har sai mun haɗa foda daban-daban guda biyu don samun daidaitaccen lanƙwasa PSD. Takaddun bayanai na kowane kuri'a sun kasance 'an yarda da su', amma sihirin yana cikin gauraya. Ba za ku koyi hakan daga takardar bayanan ba; kuna koyo da shi daga gungu-gungu.
Sintering: Inda Kayan Ya Sami Da gaske
Wannan shine dalilin rashin dawowa. Kun gyaggyara kuma kun ƙaddamar da wani 'bangaren launin ruwan kasa' mai rauni. Yanzu, a cikin tanderun sintering, ɓangarorin ƙarfe suna fuse kuma ainihin kayan kayan sun fito. Wannan shine inda zaɓinku na kayan tushe-bakin ƙarfe, ƙarfe na kayan aiki, gami na musamman-yana fuskantar gwajin sa ta wuta. Kulawar yanayi shine sarki. Ƙananan iskar oxygen a cikin yanayin hydrogen-nitrogen lokacin da aka haɗa karfe mai dauke da chromium kamar 17-4PH zai iya rage carbon na sama kuma ya lalata juriya na lalata. Mun koyi yadda ake tafiyar da ɓangarori kafin kowane muhimmin tsari don 'gwajin' yanayin tanderun, manufar inshora mai arha.
Zagayowar sintering kanta girke-girke ce ta musamman. Ramp rates, riƙe yanayin zafi, saurin sanyaya - duk su ne ke ba da umarni na ƙarshe. Don aikin da ke buƙatar gariyar maganadisu mai laushi (kamar Fe-50% Ni), ƙimar sanyaya daga zafin jiki yana da mahimmanci don haɓaka ƙarfin maganadisu da ake so. Yayi sauri sosai, kuma mun rasa taga dukiya. Ya ɗauki tanderu uku yana gudana tare da tweaks masu sanyaya da hankali don buga ƙayyadaddun bayanai. 'kayan' akan odar siyan shine kawai Fe-50Ni. An halicci kayan aiki a cikin tanderun.
Ragewa shine ɗayan babban canji, kai tsaye daura da kayan abinci. Muna nufin rage isotropic, amma ba daidai ba ne. Don madaidaicin ɓangaren kayan aiki, dole ne mu ƙirƙira rami mai ƙira dangane da ƙayyadaddun yanayin raguwa da muka haɓaka don takamaiman kayan abinci na alloy na 4140, ba da'awar 15-18% na dillali ba. Matsayinmu shine 16.7% ± 0.3% a cikin jirgin sama mai mahimmanci. Wannan madaidaicin ya fito ne daga auna ɗarurruwan ɓangarori da kuma daidaita baya. Irin ilimin abin duniya ke nan da ke zama a cikin littafin wasan kwaikwayo na kamfani.
Me yasa Alloys Kamar Cobalt da Nickel Canza Wasan
Motsawa daga bakin karfe gama gari zuwa masarautu kamar cobalt na tushen gami ko nickel tushen gami don MIM shine canjin mataki a cikin wahala da farashi. Waɗannan ba kawai 'fancier steels' bane. Gilashin su na iya zama kunkuntar sosai. Alamar cobalt-chromium-molybdenum don amfani da ilimin halitta na iya raguwa a cikin tagar Celsius 20-digiri don cimma cikakkiyar yawa ba tare da girmar hatsi ba. Rasa shi, kuma kuna samun ko dai saura porosity ko embrittlement.
Cire dauri na waɗannan allunan aiki mai girma shima ya fi wayo. Fodarsu sau da yawa sun fi mayar da martani, don haka za a iya fifita rarrabuwar kayyade (amfani da tururin acid nitric, alal misali) akan hanyoyin zafi a hankali don guje wa gurɓacewar ƙasa. Wannan yana ƙara rikitarwa tsari da farashi. Amma abin da ake biya shine sassan da kaddarorin da ke kusa da kayan aiki - yi tunanin injin injector masu jujjuya man fetur da aka yi ta hanyar MIM daga nickel superalloy. Ƙimar tana cikin sarƙaƙƙiyar sifar hanyar sadarwa, ba kawai farashin kayan ba.
Wannan yanki ne inda zurfin ganowa da ƙwarewar mashin ɗin ya zama mai kima. Kamfanin da ke da dogon tarihi a cikin simintin saka hannun jari da sarrafa gami na musamman, kamar Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), yana kawo hangen nesa daban-daban ga MIM. Sun kasance suna mu'amala da ƙarfe na ƙarfe musamman gami shekaru da yawa ta hanyar harsashi da ayyukan simintin saka hannun jari. Wannan ilimi mai zurfi game da yadda waɗannan karafa ke aiki a ƙarƙashin zafi, yadda suke mu'amala da yanayi, da kuma yadda za a iya gama su babbar kadara ce yayin da ake ƙera su. Sun fahimci cewa jihar bayan-sintering ita ce kawai farawa don sassa da yawa, wanda zai buƙaci daidai Injin CNC don saduwa da haƙuri na ƙarshe akan mahimman fasali. An tsara tsarin MIM da zaɓin kayan tare da wannan matakin mashin ɗin na gaba.
Haɗin Mashin ɗin: MIM Ba Koyaushe Yake Ma'anar 'Gama'
Rashin fahimta na gama gari shine sassan MIM suna fitowa daga tanderun da aka shirya don amfani. Ga mutane da yawa, i. Amma don aikace-aikacen madaidaici, sintering yana biye da ayyukan sakandare. Wannan yana da mahimmanci don zaɓin abu. Kuna iya zaɓar matakin da aka riga aka yi tauri, ko wanda za'a yi masa magani da zafi bayan an haɗa shi. Amma kuma dole ne ku yi la'akari da machinability. Bangaren MIM mai ɓarna yana da ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun tsari, amma ba koyaushe mafarki ne na inji ba. Yana iya zama abrasive.
Muna da shari'a tare da 440C bakin karfe MIM wanda ke buƙatar rami mai taɓawa. Bangaren ya kasance cikakke mai yawa kuma mai wuya bayan an gama. Taɓa shi kai tsaye yana tauna kayan aiki. Dole ne mu daidaita sake zagayowar sintering don barin shi a cikin ɗan ƙaramin yanayi mai laushi don mashin ɗin, sannan mu ƙara maganin zafi mai ƙarfi na gaba. Tsarin 'kayan' ya kasance haka: ƙirar abinci -> gyare-gyare -> ƙaddamarwa -> sintering (laushi) -> CNC machining -> maganin zafi -> samfurin ƙarshe. Tafiyar kayan bai kare ba bayan tanderun.
Wannan haɗaɗɗen ra'ayi shine maɓalli. Shi ya sa wasu daga cikin ƴan wasan da suka yi nasara ba shagunan MIM ba ne. Su masana'antun haɗaka ne, kamar QSY, waɗanda ke haɗa matakai. Za su iya kallon zane don hadaddun, babban kayan gami da yin hukunci ko zuba jari, MIM, ko tsarin haɗin kai ya fi dacewa akan lissafi, abu, da girma. Shekarunsu na 30 a cikin simintin gyare-gyare da injina yana nufin sun zaɓi kayan MIM tare da cikakkiyar fahimtar duk sarkar masana'anta, ba kawai matakan gyare-gyare da gyare-gyare ba. Sun san cewa ainihin farashin kayan ya haɗa da yadda yake aiki a kowane aiki na gaba.
Kasawa da darussan da suke bugawa
Ba kwa koyon kayan aiki daga nasara. Kuna koya daga kwandon shara. Tun da farko, mun yi ƙoƙari mu gudanar da kayan abinci mara ƙarancin ƙarfe na ƙarfe wanda ake nufi don sassan mota. Sassan sun yi kyau, sunyi kyau sosai. Amma a gwajin feshin gishiri, sun yi tsatsa cikin sa'o'i, yayin da wani sashi na injina na al'ada na aji iri ɗaya ya ɗauki makonni. Mai laifi? Asarar Carbon a lokacin sintering saboda yanayin da bai dace da yanayin sinadarai na musamman na foda ba. Kayan 'makin' yayi daidai, amma tsarin ya canza ingantaccen tsarin sa. Dole ne mu canza zuwa wani foda da aka ƙera don MIM, tare da wuce gona da iri daban-daban, kuma mu ƙara matsawa ƙa'idar tanderu. Takaddun takaddar ba ta da amfani idan ba mu sarrafa tsarin da ya haifar da abu na ƙarshe ba.
Wani lokaci kuma, mun bincika ta amfani da tungsten mai nauyi mai ƙarfi na MIM. Yawan yawa yana da ban mamaki, amma kayan abinci ya kasance sananne da wuya a iya ƙirƙira akai-akai. Mun shafe watanni akan ƙirar ƙofa da mai gudu, yanayin sanyi, sigogin allura. Mun sami sassa masu aiki, amma yawan amfanin ƙasa bai taɓa yin tasiri a tattalin arziƙi ba don ƙarar. Mun ajiye shi. Kayan yana da alƙawarin akan takarda, amma zahirin gaskiya na canza shi daga kayan abinci zuwa abin dogaro ya kashe aikin. Wannan kira ne mai mahimmancin hukunci da kuke yi kawai ta ƙoƙari da kasawa.
Don haka lokacin da na yi tunani akai karfe allura gyare-gyaren kayan yanzu, ba kawai ina ganin jerin gami ba. Ina ganin tarin yanke shawara: siffar foda da girman, sinadarai mai ɗaure, ɗora foda, hanyar debind, bayanin yanayin tanderu, yuwuwar magani mai zafi, da mashin ɗin da ya dace. Kayan shine wannan duka sarkar. Yana da ƙayyadaddun tsari. Samun shi daidai yana nufin mutunta kowace hanyar haɗin gwiwa, kuma ilimin ba a siya ba—an gina shi ɓangare ta ɓangaren, gazawa ta gazawa, tsawon shekaru. Bambanci ne tsakanin odar foda da aikin injiniya wani sashi.
