Intisari elh dilut kermik orundum @αEel2y3A menggunkn seruk el2y3 dn msingEmsing ditmhX IHD ISD PH dn PS% @ertA Qel2y3FPiy2D digiling PR jmD lolos ykn PHH meshD dikeringkn IIH• gD dietk SH wpD dn disintering pd suhuX IQHHD IRHHD ISHH dn ITHH• gF eesr PH% ditif Qel2y3FPiy2 dn suhu sintering ITHH• g merupkn kondisi optimumD menghsilknX densits a QDRU gGm 3 D porosits a HDTR%D kekersn @rvA a IRSR kgfGmm 2 D kut pth a QIQ wD dn koe¢sien ekspnsi terml a TDQ x IH −6 • g −1 F gorundum @αEel2y3A merupkn fs dominnD prtikelny ultD grin sizeX HDQEHDV µm dn minorny dlh mullite @el2y3FPiy2AD erentuk jrumD dn grin sizeX HDQEQDH µmF KATA KUNCI: ? I. PENDAHULUAN emutn kermik lumin @αEel 2 y 3 A yng pdt dn kut memerlukn suhu sintering yng tinggiD yitu sekitr IVHH E IWHH• g IF uermik αEel 2 y 3 tergolong kermik oksidD memiliki titik leur sekitr PHSH• gD ersift isoltor listrikD kutD kers dn thn suhu tinggiF lh stu r unE tuk menurunkn suhu sintering dlh dengn memperkeil ukurn utir hingg dlm orde nno size dnGtu penmE hn ditif tertentu yng mempunyi titik leur leih rendh dri lumin PF ift ¢sis el 2 y 3 ntr linX densits a QDWT gGm 3 D kekersn a ISHH E IVHH kgfGmm 2 D kut tekn a PQH E QSH w dn koe¢sien ekspnsi terml a @V E WA x IH −6 • g −1 F emkin kermik lumin ukup lusD idng meknik @bearingD cutting tollsD inner liningAD idng elektronik @isolE tor listrikD sustrt elektronikAD idng medis segi io mE teril dn hn refrktori suhu tinggiF emilihn hn ditif mullite @Qel 2 y 3 FPiy 2 AD kren mempunyi keungguln dri segi kekutn meknikny Q dn jug leih thn terhdp kejut suhu @thermal shock resistanceA tu erkitn dengn nili koe¢sien ekspnsi terml yng rendhF erpdun ntr lumin dn mullite pd mteril kermik αEel 2 y 3 dlh sngt teptD pil diliht dri pliksinyX hot plateD roller kilnD crucible dn lining brickF uomponenEkomponen dits merupkn kelengkpn tungku yng diutuhkn pd indusE tri kermikD gels dn pengeorn logmF egi hn pemikirnD hw komponen terseut eredr di sndonesi ternyt msih diimport dri lur negeriF k klh pentingny jug dlh ketersedin hn ku lm di sndonesi ukup nykD ik erup minerl uxit segi sumer el 2 y 3 dn psir silik segi sumer iy 2 F yleh kren itu perlu dilkukn penelitin dn kjin yng erkitn dengn lih teknologi dn pengusn tentng pemE utn kermik lumin @αEel 2 y 3 A dpt diterpkn khususE * E-MAIL: angg005@lipi.go.id ny di sndonesiF d tulisn ini dihs tt r pemutn kermik αEel 2 y 3 dengn vrisi penmhn ditif mullite @el 2 y 3 FPiy 2 A dn suhu sinteringF eruk mullite @el 2 y 3 FPiy 2 A diut dengn perndingn P mole siE lik @iy 2 A dn Q mole lumin @el 2 y 3 AD digiling selm PR jm dn dikrGklsinsi pd suhu IQHH• g dn diE thn pd suhu terseut selm P jm RF uomposisi mullite @el 2 y 3 FPiy 2 A yng ditmhkn pd pemutn kermik lumin @el 2 y 3 A dlh IHD ISD PH dn PS% @ertA Qel 2 y 3 FPiy 2 D vrisi suhuX IQHHD IRHHD ISHH dn ITHH• gD merupkn lnjutn penelitin seelumny SF urkteristik yng dimtiX densitsD porositsD kekersn @rvAD kut pthD koe¢sien ekspnsi terml dn nlis struktur mikro dengn menggunkn h dn iwF II.DASAR TEORI enyw lumin ersift polimorf dn struktur αEel 2 y 3 tu sering diseut d...
` AbstrakTelah dilakukan proses penghalusan serpihan NdFeB dengan menggunakan metode dry milling dalam atmosfir gas inert dengan menggunakan gas Nitrogen (N2) dengan bahan awal yang digunakan berupa serpihan NdFeB dengan waktu milling yang divariasikan selama 8 jam, 16 jam, 24 jam dan 48 jam. Besaran magnetik yang diukur adalah koersivitas (Hc), induksi remanensi magnetik (Br) dan energi produk maksimum (BHmaks). Proses preparasi sampel dimulai dengan penghalusan serpihan dengan berbagai variasi waktu milling, dicetak dengan gaya 7 tonf selama 2 menit, dan dengan ditambahkan bahan perekat celuna sebanyak 3 wt%, hingga membentuk pelet dengan diameter ±1,6 cm. Selanjutnya sampel pelet di heat treatment selama 1 jam pada suhu 170ᵒC dan setelah itu dilakukan coating pada sampel. Sampel pelet yang telah melalui proses heat treatment, dimagnetisasi dengan impulse magnetizer pada tegangan 1500V DC. Sampel pelet yang telah dimagnetisasi diukur fluks density menggunakan Gaussmeter. Dari nilai densitas fluks magnet sampel, diperoleh sampel terbaik yaitu sampel hasil milling selama 48 jam pada suhu heat treatment 170ᵒC dan diperoleh fluks magnet sebesar 485,8 Gauss. Koersivitas pelet NdFeB yaitu 1,171 kOe dan BHmaks sebesar 0,62 MGOe. Kata-kata kunci: NdFeB, heat treatment, dry milling, gas inert AbstractParticle refining process of flakes NdFeB by dry milling method within an inert gas atmosphere using Nitrogen gas (N2) with based material was flakes NdFeB and with milling time parameters were variated for 8 hours, 16 hours, 24 hours and 48 hours had been done. The measured magnetic properties were coercivity (Hc), remanence (Br) and maximum energy product (BHmax). The preparation raw material process was started with particle refining with milling time variety, then it was pressed with 7 tonf force for 2 minutes and with added adhesive celuna as much as 3 wt% up to become pellets form with a diameter ±1.6 cm. Further the pellet samples were given heat treatment for 1 hour at temperature 170ᵒC and after that all the samples were coated. Pellet samples that have been done heat treatment, were magnetized with the impulse magnetizer in 1500V DC voltage. Pellet sample that had been magnetized ,its flux density was measured by using a Gaussmeter. From the magnetic flux density sample value, the best sample that obtained was the sample in milling time for 48 hours at heat treatment's temperature was 170ᵒC and obtained magnetic flux density at 485.8 Gauss. The NdFeB pellet coercivity was 1.171 kOe and the BHmax was 0.62 MGOe.
In this study, we made ceramic magnet of barium hexaferrite (BaFe12O19) with variation of milling time and sintering temperature by powder metallurgy method. First, barium hexaferrite powder mashed with a rotary ball mill. Milling is done with medium of water (wet milling) for 4 hours and 12 hours. Then, the sample is dried for 24 hours and printed with a load of 8 tons for 1 minute. Then, the pellet-shaped sample sintered at a temperature of 1100 °C and 1200 °C with a holding time of 1 hour. The density and porosity measurements were carried out using the Archimedes Method, phase analysis with XRD, and magnetic flux density using gaussmeter. The highest density were found in samples that were milled for 12 hours and sintered at the temperature of 1200 °C ie 4.495 gr/cm3. In that sample also obtained the lowest porosity 0.89%. From XRD analysis, we knew that hematite (Fe2O3) was found as impurity phase. From gaussmeter, the samples with the highest magnetic flux density were found in samples that were milled for 4 hours and sintered at a temperature of 1200 °C ie 410.3 G.
The permanent magnets based on NdFeB is well known as rare earth alloy magnets made from neodymium, iron and boron elements and has tetragonal crystalline structure Nd2Fe14B which has high coercivity, large energy product (app 50 MGOe) and curie temperature about 312 °C. In this paper will be discussed the preparation of bakelite bonded magnet NdFeB and characterization, also the purpose of this research is to make bonded magnet NdFeB using 3 % bakelite and know the extent to which can be applied in making a small electric generator. The bonded magnet NdFeB was made by mixing a magnetic powder NdFeB with a polymer as binder. The composition of the sample consisted of 97 wt. % of NdFeB powder and 3 wt.% of bakelite. The mixed raw materials were then pressed to form a disc with pressure about 40 MPa at temperature about 160 °C for 20 minutes. It was obtained a disc with size 40 x 18 x 6 mm. The disc samples were magnetized by using impulse magnetizer at 1500 Volt DC, then the samples were measured magnetic properties by using Gauss meter and Permeagraph. The measurements result show that, the bakelite bonded magnet NdFeB has Magnetic Flux = 1100 Gauss, Remanence Br = 5.20 kGauss, Coercivity Hc = 6.14 kOe and Energy product (BH) max = 4.78 MGOe. The bonded magnet NdFeB was applied to the prototype small generator with single rotor and single stator. The results of performance test of generator indicate that it is achieved output power of generator about 9.98 Watt at a maximum speed about 500 rpm.
Hasil belajar mahasiswa merupakan unsur yang sangat penting dalam pencapaian tujuan Pendidikan. Survei pendahaluan menunjukkan bahwa hasil belajar mahasiswa di STAB Dharma Widya saat ini tidak sesuai dengan yang diharapkan dengan kenyataaan, oleh karena itu hasil belajar mahasiswa menarik untuk diteliti. Penelitian ini bertujuan untuk mengetahui bagaimana hasil belajar mahasiswa itu dapat ditingkatkan dengan cara meneliti pengaruh antara hasil belajar mahasiswa dengan variabel lain yaitu minat dan motivasi belajar secara sendiri-sendiri maupun secara bersama-sama. Penelitian ini dilakukan dengan secara kuantitatif dengan metode survey. Populasi dalam penelitian ini adalah seluruh mahasiswa aktif Sekolah Tinggi Agama Budha Dharma Widya sejumlah 89 mahasiswa. Data dikumpulkan melalui kuisioner, dan dianalisis dengan statistik regresi- korelasi. Hasil penelitian menunjukkan bahwa terdapat pengaruh positif antara minat dengan hasil belajar mahasiswa dengan koefisien korelasi ry1=0,901, terdapat hubungan positif antara motivasi dengan hasil belajar mahasiswa dengan koefisien korelasi ry2=0,988, terdapat pengaruh yang positif minat dan motivasi secara bersama-sama dengan hasil belajar mahasiswa, dengan koefisien korelasi ry12=0,991. Hal ini menunjukkan bahwa hasil belajar mahasiswa dapat ditingkatkan melalui peningkatan minat dan motivasi belajar baik secara sendiri - sendiri maupun secara bersama-sama.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.