Ƙarfafa Ƙarfin Ƙarfin Magnets na SLS NdFeB ta hanyar Shigar da Iyakar Ƙwayoyi

2.1 Tsarin Sintering na Laser na Zaɓaɓɓu

Sabanin daidaitaccen LPBF wanda ke narkar da foda gabaɗaya, wannan aikin yana amfani da dabarar sintering. Ana amfani da foda mai siffar yanki na kasuwanci na NdFeB (Magnequench MQP-S-11-9) ta hanyar amfani da laser. Babban gyaran siga shine rage ƙarfin laser don guje wa narkewa gabaɗaya, don haka kiyaye ainihin tsarin ƙwayoyin ƙwayoyin nano na ɓangarorin foda (girman ƙwaya ~50 nm). Wannan yana da mahimmanci saboda narkewa gabaɗaya da narkewa cikin sauri yawanci yana haifar da girma ƙwayoyi da canza sinadarai na iyakar ƙwayoyi, waɗanda ke cutar da ƙarfin ƙarfi. Tsarin yana nufin kusan cikakken yawa yayin kiyaye kaddarorin maganadisu na farkon foda.

2.2 Gawaɗan Yaduwar Iyakar Ƙwayoyi

An yi amfani da gawaɗan guda uku masu narkewa cikin sauƙi don shiga ciki:

• Nd-Cu: Gawaɗan binary na asali don samar da ci gaba da yawa, ba na ferromagnetic ba mai yawan Nd a iyakar ƙwayoyi.
• Nd-Al-Ni-Cu: Gawaɗan da ya ƙunshi abubuwa da yawa da nufin inganta yanayin iyakar ƙwayoyi da rarrabawa.
• Nd-Tb-Cu: Bambance-bambancen mai inganci. Tb (Terbium) yana yaduwa zuwa cikin harsashi na waje na ƙwayoyin Nd₂Fe₁₄B, yana samar da harsashi na (Nd,Tb)₂Fe₁₄B tare da mafi girman bambance-bambancen magnetocrystalline.

An gudanar da GBDP ta hanyar lulluɓe magnet ɗin da aka sinter tare da gawaɗan kuma ana amfani da maganin zafi a ƙarƙashin zafin sintering na magnet, yana barin aikin capillary ya ja narkakken gawaɗan tare da iyakokin ƙwayoyi.

3.1 Sakamakon Ƙarfafa Ƙarfin Ƙarfi

GBDP ya haifar da haɓaka mai ban mamaki a cikin ƙarfin ƙarfi na ciki (H_cj). Magnet na SLS na asali ya nuna H_cj ≈ 0.65 T. Bayan shiga tare da gawaɗan Nd-Tb-Cu, H_cj ya kai kusan 1.5 T. Gawaɗan Nd-Cu da Nd-Al-Ni-Cu suma sun ba da gagarumin ci gaba, ko da yake ƙasa da gawaɗan da ke ɗauke da Tb. Wannan ya tabbatar da cewa haɓakar haɗakar sakamako ne guda biyu: 1) ingantaccen keɓance iyakar ƙwayoyi (daga duk gawaɗan) da 2) ƙara filin nucleation don jujjuyawar yanki (musamman daga harsashi mai yawan Tb).

3.2 Siffanta Tsarin Ƙananan Ƙwayoyi

Cikakken bincike ta hanyar Duban Electron Microscopy (SEM) da Watsa Electron Microscopy (TEM) tare da Binciken X-ray Spectroscopy (EDS) ya bayyana juyin halittar tsarin ƙananan ƙwayoyi:

• Ci gaba da Tsarin Iyakar Ƙwayoyi: Wani lokaci mai yawan Nd ya samo asali tare da iyakokin ƙwayoyi, yana ware ƙwayoyin maganadisu masu wuya na Nd₂Fe₁₄B. Wannan yana hana musayar musayar tsakanin ƙwayoyi, babban tsarin aiki don jujjuyawar maganadisu da wuri.
• Samuwar Harsashi mai yawan Tb: A cikin samfuran tare da Nd-Tb-Cu, taswirar EDS ta tabbatar da yaduwar Tb zuwa cikin siririn harsashi (mai kauri da yawa nanometers) a gefen ƙwayoyin Nd₂Fe₁₄B. Filin anisotropy H_A na (Nd,Tb)₂Fe₁₄B ya fi na Nd₂Fe₁₄B girma sosai, yana ƙara ƙarfin ƙarfi kai tsaye bisa ga tsarin nucleation: $H_c \propto H_A - N_{eff}M_s$, inda $N_{eff}$ shine ingantaccen ƙimar demagnetizing kuma $M_s$ shine magnetization mai cika.
• Kiyaye Girman Ƙwaya: Da mahimmanci, tsarin SLS+GBDP ya kiyaye girman ƙwayoyin nano. Wannan yana da mahimmanci saboda ƙarfin ƙarfi a cikin magnets na NdFeB yana da alaƙa da girman ƙwaya har zuwa iyakar yanki ɗaya (~300 nm). Ƙwayoyin da aka kiyaye suna ba da gudummawa ga babban ƙarfin ƙarfi.

Bayanin Jadawali (Ra'ayi): Jadawali mai sanduna zai nuna "Ƙarfin Ƙarfi (Hcj)" akan Y-axis (0 zuwa 1.6 T). Sanduna uku: 1) "SLS Kawai" a ~0.65 T, 2) "SLS + Nd-Cu GBDP" a ~1.1 T, 3) "SLS + Nd-Tb-Cu GBDP" a ~1.5 T. Jadawali na biyu, zane mai tsari, zai kwatanta tsarin ƙananan ƙwayoyi: ƙwayoyin Nd₂Fe₁₄B masu girman nano (launin toka) da ke kewaye da siriri, mai haske mai yawan Tb (orange) kuma an saka su a cikin ci gaba da yawa na iyakar ƙwayoyi mai yawan Nd (shuɗi).

4.1 Babban Fahimta & Tsarin Ma'ana

Babban hazakar takardar yana cikin dabarar ingantawa da aka raba. Maimakon yin yaƙi da ciniki na asali a cikin saitin sigogi na tsarin AM guda ɗaya, ya raba matsalar: Yi amfani da SLS don siffa da yawa, kuma yi amfani da GBDP don tsarin ƙananan ƙwayoyi da aiki. Wannan tunanin injiniya ne mai zurfi. Tsarin ma'ana ba shi da aibi: 1) Gano ƙarancin ƙarfin ƙarfi na AM, 2) Zaɓi tsari (SLS) wanda ke kiyaye ƙwayoyin nano masu amfani, 3) Aiwatar da ingantaccen dabarar haɓaka magnet (GBDP) a cikin sabon yanayi, 4) Tabbatar da tare da mafi girman gawaɗan aiki (tushen Tb). Wannan lamari ne na gargajiya na ƙirar kayan haɗin gwiwa da saduwa da ci gaban masana'antu.

4.2 Ƙarfafawa & Kurakurai Masu Muhimmanci

Ƙarfafawa: Ƙarfin ƙarfi na 1.5 T sakamako ne na halitta ga magnet na AM kuma yana haɗa gibin ma'ana zuwa ga takwarorinsu da aka sinter. Shaidar tsarin ƙananan ƙwayoyi tana da ƙarfi. Hanyar tana da inganci ta kayan aiki—Ana amfani da Tb kawai a saman ƙwayoyi, yana rage amfani da wannan muhimmin sinadari na ƙasa mai wuya idan aka kwatanta da haɗa gawaɗan gabaɗaya, babbar fa'ida ta farashi da sarkar samarwa kamar yadda Cibiyar Muhimman Kayan Aiki ta Ma'aikatar Makamashi ta Amurka ta bayyana.

Kurakurai Masu Muhimmanci & Tambayoyin da ba a amsa ba: Giwa a cikin daki shine remanence (B_r) da mafi girman aikin makamashi ((BH)_max). Takardar tana shiru sosai akan wannan. GBDP, musamman tare da matakan iyakar ƙwayoyi marasa maganadisu, yawanci yana rage remanence. Menene ribar gabaɗaya a cikin (BH)_max? Ga masu ƙirar injina, wannan sau da yawa yana da mahimmanci fiye da ƙarfin ƙarfi kaɗai. Bugu da ƙari, tsarin yana ƙara rikitarwa—magungunan zafi guda biyu (sintering + yaduwa)—wanda ke tasiri farashi da kayan aiki. Scalability na rufi daidai da shiga cikin sifofi masu rikitarwa na 3D tare da tashoshi na ciki ya kasance ƙalubale mai mahimmanci na injiniya, ba kamar sifofi masu sauƙi da ake amfani da su a cikin nunin sikelin dakin gwaje-gwaje ba.

4.3 Fahimta Mai Aiki & Tasirin Dabarun

Ga ƙungiyoyin R&D: Dakatar da ƙoƙarin magance komai tare da laser. Wannan aikin ya tabbatar da cewa matakai na haɗin gwiwa shine makomar nan gaba don AM na kayan aiki masu aiki. Abin aiki nan take shine a maimaita wannan binciken amma tare da cikakken jerin ma'aunin kaddarorin maganadisu (cikakken madauki B-H, dogaro da zafin jiki).

Ga masu dabarun masana'antu: Wannan fasaha mai yuwuwa ce mai ba da dama don aikace-aikace masu daraja, ƙarancin girma inda rikitarwar siffa ke ba da hujjar farashin tsari—tunanin injunan motoci na musamman don sararin samaniya, mutum-mutumi, ko na'urorin likita. Ba maye gurbin da aka yi masa kwalliya ba ne don magnets da aka yi da yawa ba tukuna. Tasirin dabarun shine canzawa zuwa samfuran kayan aiki-a-matakin sabis, inda masana'antun ke ba da ba kawai bugawa ba, amma cikakken aikin sarrafawa bayan aiki na haɓaka aiki. Kamfanoni yakamata su saka hannun jari a cikin haɓaka dabarun shiga ciki don sassa masu rikitarwa, watakila suna zana wahayi daga ƙalubale iri ɗaya da aka warware a cikin masana'antar jefa ƙarfe (MIM) tare da taimakon sintering.