1,720,997 research outputs found
Pengaruh Aditif Mgo/Cao dan Suhu Sintering terhadap Mikrostruktur dan Karakteristik Keramik PSZ
No full textPartially Stabilized Zirconia (PSZ) is a toughness ceramic, and they can be used for cutting tool equipment and bio ceramic. The partially stabilized Zirconia was be made by using additive 12 % MgO and 8,64 % CaO. Powder preparation was be done by using precipitation method, where raw materials MgCl2 or CaCl2 and ZrOCl2.8H2O were mixed with water and added ammonia solution until found precipitat. The precipitat was dried in drying oven at 100°C for 24 hours, and then calcined at 800°C. The powder waspulverized and sieved until- 400 mesh, Then pressing at 5 ton. The all samples were sintered at temperature 1100 -c until 1500 -c with interval 100°C and hold for 3 hours. The characterization is such as : testing of physical and mechanical properties (porosity, density, hardness, toughness, bending strength, and coefficient thermal expansion), analysis of microstructure by using XRD and SEM. The characterization results show that ceramic powder of Mg-PSZ and Ca-PSZ after calcination have average particle size about 4,07 ?m and 4,12 ?m . According to microstructure analysis show that tetragonal, monoclinic and cubic phases were formed with grain size about 0,1 ?m - 20 ?m for both samples. The optimum condition was obtained at sintering temperature 1500ºC with the result as: • MG-PSZ ceramics gas physical and mechanical properties such as: density = 5,41 g/ cm3, porosity = 10,4%, hardness = 11,2 GPa, toughness = 3,535 MPa-?m,bending strength = 570 Mpa. • Ca-PSZ ceramics gas physical and mechanical properties such as: density = 5,16 g/cm3, porosity - 13,1%, hardness = 10,7 GPa, toughness = 3,474 MPa-?m, bending strength = 611,6 Mpa. From the measurement of thermal expansion result shows that ceramic Mg-PSZ and Ca-PSZ has coefficient thermal expansion about (10 - 21) x 10-6C0-1Partially Stabilized Zirconia (PSZ) merupakan bahan keramik yang tangguh sehingga dapat digunakan sebagaialat cutting toll dan bio ceramic. Telah dilakukan pembuatan keramik PSZ dengan komposisi aditif sebesar 12 % MgO dan 8,64 % CaO. Proses preparasi sampel dilakukan melalui metoda kopresipitasi dengan cara pencampuran serbuk MgCl2 atau CaCl2 dengan serbuk ZrOCl2•8H2O dalam air dan ditambahkan ammonia hingga membentuk endapan. Endapan ini selanjutnya dikeringkan di dalam oven dengan suhu pemanasan 100°C selama 24 jam, dan dikalsinasi 800°C . Serbuk yang dihasilkan di baluskan dan diayak hingga lolos ayakan 400 mesh, dicetak dengan tekanan sebesar 5 ton. Benda yang telah dicetak tekan kemudian disintering pada suhu 11OO°C hingga 1500°C dengan interval kenaikan suhu sebesar 100°C dan masing-masing ditahan selama 3 jam. Karakterisasi yang dilakukan meliputi: pengujian sifat fisis dan mekanik (porositas, densitas, kekerasan, ketangguhan, kuat patah, dan koefisien ekspansi termal), sedangkan analisa mikrostruktur dilakukan dengan menggunakan XRD dan SEM. Dari basil kalsinasi serbuk keramik Mg-PSZ dan Ca-PSZ pada suhu 800ºc diperoleh ukuran butir rata-rata sebesar 4,07?m dan 4,12?m. Berdasarkan hasil analisa struktnr mikro menunjukkan bahwa telah terbentuk fasa monoklinik, tetragonal dan kubik dengan ukuran butir yang diperoleh berkisar 0,1 ?m – 20 ?m . Kondisi optimum dicapai pada suhu sintering 1500°C dengan hasil sebagai berikut: • Keramik Mg-PSZ menghasilkan sifat fisis dan mekanis : densitas - 5,41 g/cm3, porositas 10,41 %, kekerasan = 11,2 GPa, ketangguhan = 3,535 MPa?m , kekuatan patah = 570 Mpa. • Keramik Ca-PSZ menghasilkan sifat fisis dan mekanis : densitas = 5,16 g/cm3, porositas = 13,1 %, kekerasan = 10,7 GPa, ketangguhan = 3,474 MPa?m, kekuatan patah = 611,6 Mpa. • Dari hasil pengukuran koefisien ekspansi termal keramik Mg-PSZ dan Ca-PSZ diperoleh berkisar antara (10-21) x 10-6C0-1 en_US103 HalamanTesis Magiste
Pembuatan Magnet Bonded Permanen PrFeB dengan Binder Polyester dan Silicone Rubber
No full textResearch on fabrications bonded magnets PrFeB type MQEP 16-7 with polyester
and silicone rubber binder has been done. The purpose of this study is
determination of the effect of polyester and silicone rubber matrix on the
mechanical and magnetic properties in the manufacture of bonded magnets
PrFeB. The process of fabrications bonded magnets PrFeB made by mixing
powder and magnets PrFeB respectively - each with variations binder
composition (wt%) are 2, 4, 6, and 8. For each sample takes 8 grams total mass of
bonded magnets PrFeB. Once the powder mixture is made, then printed using
compression molding method with a sample pressure of 5 tons. Curing
temperature of 150° C for samples bonded magnet with polyester binder and
room temperature for samples bonded magnet with silicone rubber binder. The
results showed that the best magnetic field derived from the manufacture of
bonded magnets with the addition of 2% silicone rubber binder at 1156.9 G and
energy product (BH)max 9.15 MGOe, as well as the value of 10.4 BHN Brinell
hardness and compressive strength of 22, 3 MPa.80 HalamanSkripsi Sarjan
Optimasi Proses Pembuatan Hard-Magnetic Material Berbasis Bafe12o19 dengan Aditif Femn
No full textHas been done manufacturing of the magnet permanent Barium Hexaferrite
(BaFe12O19) with the addition of additives Ferromanganese (FeMn) variations in
composition 3 and 7 (wt%) using the mechanical alloying method. Powder of
BaFe12O19 and FeMn mixed using HEM for 15 minutes (dry milling). Samples
were pressed with pressure 40kgf/cm2 using a magnetic field press in 3.6 kG
magnetic field. Samples were sintered using the High Temperature Furnace at
1100, 1150, 1200 and 1250oC for 2 hours. Samples were characterized on
physical properties (bulk density, porosity), the microstructure analysis using
XRD and magnetic properties using the VSM. It was found that the additive 3 wt.
% FeMn with 1200oC as the sintering temperature (2 hours) has the highest
magnetic and physical properties where the bulk density at 4.81 g/cm3, porosity at
20%, the saturation at 63.49 emu/g, remanence at 31.45 emu/g, coercivity at 3
kOe, and BHmax = 630 kGOe.132 HalamanSkripsi Sarjan
Pengaruh Aditif Mgo/Cao dan Suhu Sintering terhadap Mikrostruktur dan Karakteristik Keramik PSZ
No full textPartially Stabilized Zirconia (PSZ) is a toughness ceramic, and they can be used for cutting tool equipment and bio ceramic. The partially stabilized Zirconia was be made by using additive 12 % MgO and 8,64 % CaO. Powder preparation was be done by using precipitation method, where raw materials MgCl2 or CaCl2 and ZrOCl2.8H2O were mixed with water and added ammonia solution until found precipitat. The precipitat was dried in drying oven at 100°C for 24 hours, and then calcined at 800°C. The powder waspulverized and sieved until- 400 mesh, Then pressing at 5 ton. The all samples were sintered at temperature 1100 -c until 1500 -c with interval 100°C and hold for 3 hours. The characterization is such as : testing of physical and mechanical properties (porosity, density, hardness, toughness, bending strength, and coefficient thermal expansion), analysis of microstructure by using XRD and SEM. The characterization results show that ceramic powder of Mg-PSZ and Ca-PSZ after calcination have average particle size about 4,07 ?m and 4,12 ?m . According to microstructure analysis show that tetragonal, monoclinic and cubic phases were formed with grain size about 0,1 ?m - 20 ?m for both samples. The optimum condition was obtained at sintering temperature 1500ºC with the result as: • MG-PSZ ceramics gas physical and mechanical properties such as: density = 5,41 g/ cm3, porosity = 10,4%, hardness = 11,2 GPa, toughness = 3,535 MPa-?m,bending strength = 570 Mpa. • Ca-PSZ ceramics gas physical and mechanical properties such as: density = 5,16 g/cm3, porosity - 13,1%, hardness = 10,7 GPa, toughness = 3,474 MPa-?m, bending strength = 611,6 Mpa. From the measurement of thermal expansion result shows that ceramic Mg-PSZ and Ca-PSZ has coefficient thermal expansion about (10 - 21) x 10-6C0-1Partially Stabilized Zirconia (PSZ) merupakan bahan keramik yang tangguh sehingga dapat digunakan sebagaialat cutting toll dan bio ceramic. Telah dilakukan pembuatan keramik PSZ dengan komposisi aditif sebesar 12 % MgO dan 8,64 % CaO. Proses preparasi sampel dilakukan melalui metoda kopresipitasi dengan cara pencampuran serbuk MgCl2 atau CaCl2 dengan serbuk ZrOCl2•8H2O dalam air dan ditambahkan ammonia hingga membentuk endapan. Endapan ini selanjutnya dikeringkan di dalam oven dengan suhu pemanasan 100°C selama 24 jam, dan dikalsinasi 800°C . Serbuk yang dihasilkan di baluskan dan diayak hingga lolos ayakan 400 mesh, dicetak dengan tekanan sebesar 5 ton. Benda yang telah dicetak tekan kemudian disintering pada suhu 11OO°C hingga 1500°C dengan interval kenaikan suhu sebesar 100°C dan masing-masing ditahan selama 3 jam. Karakterisasi yang dilakukan meliputi: pengujian sifat fisis dan mekanik (porositas, densitas, kekerasan, ketangguhan, kuat patah, dan koefisien ekspansi termal), sedangkan analisa mikrostruktur dilakukan dengan menggunakan XRD dan SEM. Dari basil kalsinasi serbuk keramik Mg-PSZ dan Ca-PSZ pada suhu 800ºc diperoleh ukuran butir rata-rata sebesar 4,07?m dan 4,12?m. Berdasarkan hasil analisa struktnr mikro menunjukkan bahwa telah terbentuk fasa monoklinik, tetragonal dan kubik dengan ukuran butir yang diperoleh berkisar 0,1 ?m – 20 ?m . Kondisi optimum dicapai pada suhu sintering 1500°C dengan hasil sebagai berikut: • Keramik Mg-PSZ menghasilkan sifat fisis dan mekanis : densitas - 5,41 g/cm3, porositas 10,41 %, kekerasan = 11,2 GPa, ketangguhan = 3,535 MPa?m , kekuatan patah = 570 Mpa. • Keramik Ca-PSZ menghasilkan sifat fisis dan mekanis : densitas = 5,16 g/cm3, porositas = 13,1 %, kekerasan = 10,7 GPa, ketangguhan = 3,474 MPa?m, kekuatan patah = 611,6 Mpa. • Dari hasil pengukuran koefisien ekspansi termal keramik Mg-PSZ dan Ca-PSZ diperoleh berkisar antara (10-21) x 10-6C0-1 en_US103 HalamanTesis Magiste
Sintesis dan Karakterisasi Magnet Berbasis Barium Heksaferit - Alumina
No full textPermanent magnet based on BaFe12O19 - Al2O3 by powder metallurgy method has
been made. Variables of the research is barium hexaferrite (BaFe12O19) materials
added Al2O3 with variations in the composition of 100:0, 60:40, 50:50 and 40:60
(% weight) and the sintering temperature of 900, 950, 1000, 1050 and 1100 0C
with holding time of 2 hours. Quantities observed were include density, porosity,
flux density, hysteresis curve, microstructure analysis by XRD and SEM. From the
observation indicate that the addition of Al2O3 to produce true density ranges
from 3570 to 4450 kg/m3, green body density ranges from 2600 to 3270 kg/m3,
bulk density ranges from 4030 to 5170 kg/m3, porosity ranges from 19.28 to
24.79%, shrinkage ranges from 2.37 to 10.92%, magnetic flux density ranges
from 13.00 to 65.45 Gauss, remanence Br ranges from 0.03 to 0.20 kGauss,
coercivity HCJ ranges from 0.082 to 0.096 kOe and BHmax ranges from 0.046 to
0.290 MGOe. Both materials are generally reacted, the resulting phase structure
FeAl2O3, BaFeO3, Fe2O3, Ba3Al2O6 and Fe3O4. The morphology is relatively
homogeneous with the particle shape resembles a rod with a particle size < 1 μm.
The best composition and temperature is 40 %wt Al2O3 at a temperature of 1050
0C with a bulk density of 4340 kg/m3, porosity of 22.98%, shrinkage of 6.27% and
flux density 63.00 Gauss. The resulting permanent magnet are soft magnetic
expected to be used as recording media or microwave absorbent materialTelah berhasil dibuat magnet permanen berbasis BaFe12O19-Al2O3 melalui metode
metalurgi serbuk. Variabel penelitian yang dilakukan adalah bahan barium
heksaferit (BaFe12O19) ditambahkan Al2O3 dengan variasi komposisi 100:0, 60:40,
50:50 dan 40:60 (% berat), serta suhu sintering 900, 950, 1000, 1050 dan 1100 0C
yang masing-masing ditahan selama 2 jam. Besaran-besaran yang diamati
meliputi densitas, porositas, fluks densitas, kurva histerisis, analisa mikrostruktur
dengan XRD dan SEM. Dari hasil pengamatan menunjukkan bahwa penambahan
Al2O3 menghasilkan true density berkisar 3570-4450 kg/m3, green body density
berkisar 2600-3270 kg/m3, bulk density berkisar 4030-5170 kg/m3, porositas
berkisar 19,28-24,79%, shrinkage berkisar 2,37-10,92%, flux density magnetik
berkisar 13,00-65,45 Gauss, remanensi Br berkisar 0,03-0,20 kGauss, koersivitas
HCJ berkisar 0,082-0,096 kOe dan BHmax berkisar 0,046-0,290 MGOe. Kedua
bahan sebagian besar bereaksi, struktur fasa yang dihasilkan FeAl2O3, BaFeO3,
Fe2O3, Ba3Al2O6 dan Fe3O4. Sedangkan morfologinya relatif homogen dengan
bentuk partikel menyerupai batang dan ukuran partikel < 1 μm. Komposisi dan
suhu optimum adalah 40% wt Al2O3 pada suhu 1050 0C dengan menghasilkan
bulk density 4340 kg/m3, porositas 22,98%, shrinkage 6,27% dan flux density
63,00 Gauss. Magnet permanen yang dihasilkan bersifat soft magnetik yang
diharapkan dapat digunakan sebagai media recording atau material absorben
microwave.87 HalamanTesis Magiste
Pembuatan dan Karakterisasi Semi-Hard Magnetic Fe2O3 Berbasis Mill Scale Limbah Industri Baja dengan Penambahan FeMo
No full textSynthesis and characterisation magnetic material based on mill scale with 1, 3, 5, 7 and 9% wt FeMo addition has been done. The raw material of mill scale milled using Planetary Ball Mill (PBM) while FeMo milled using High Energy Milling (HEM) in wet milling method. And then XRF analysed has done and show the element compiler of mill scales are 98.7% iron and the other element are Mn, Si, Al, Cr, Nb and Cu. while the compiler of FeMo are 60.3% Molybdenum, 38,5% iron and there are Al, Si, Cu and Ni. Mixing process of mill scale and FeMo powder has done using HEM for 15 minutes. The true density measurement was done and the value range 5.63 – 5.93 g/cm3as the result, while VSM measurement got the coercivity about 402.64 – 442.13 g/cm3. After that, the mixed powder of mill scale and FeMo calcined at 900oC for 2 hours. And the analisys of XRD shown a single phase namely hematite (F2O3) and VSM measurement got the coercivity about 2.2 – 2.3 kOe. Than, the powder were calcined pressed with 70kgf/cm2for 2 minutes and sintered at 1150oC and 1250oC for 2 hours. The bulk density and porosity measurement show that optimum condition when the sample sintered at 1250oC and The XRD characterisation of sample sintered at 1250oC show that the phases is not change with coercivity about 0.7 – 1.2 kOe, when added 1, 5 and 9 wt % FeMo and it is conclude into semi-hard magnetic materials and can be applied as magnetic sensor and telecomunication devices. When 7 wt % FeMo added, it produced hard magnetic and can be applied as electric motors for watches and computer, printers, galvanometer, loudspeaker, microphone and Nuclear Magnetic resonance (NMR).Pembuatan dan karakterisasi material magnetik berbasis mill scale limbah industri baja dengan penambahan 1, 3, 5, 7 dan 9% wt FeMo telah dilakukan. Bahan baku mill scale dimilling menggunakan Planetary Ball Mill (PBM) sedangkan FeMo dimilling menggunakan High Energy Milling (HEM) dengan metode wet milling. Kemudian dilakukan pengujian XRF dan menunjukkan kandungan mill scale adalah 98,7% Fe dan unsur lain berupa Mn, Si, Al, Cr, Nb dan Cu sedangkan unsur penyusun FeMo adalah 60,3% Mo dan 38,5% Fe dan unsur lain seperti Al, Si, Cu, dan Ni. Kemudian serbuk mill scale dan FeMo dimixing menggunakan HEM selama 15 menit. Dilakukan Pengujian true density dimana hasilnya berkisar 5,63 – 5,93 g/cm3 dan pengukuran VSM menunjukkan nilai koersivitas berkisar 402,64 – 442,13 g/cm3. Kemudian campuran serbuk mill scale dan FeMo dikalsinasi pada suhu 900oC (2 jam) dan dilakukan Karakterisasi XRD dan VSM dimana hasilnya menunjukkan telah terbentuknya fasa tunggal Fe2O3 (hematit) dengan nilai koersivitas berkisar 2,2 – 2,3 kOe. Bahan yang telah dikalsinasi tersebut dikompaksi (70kgf/cm2) dan disintering pada suhu 1150oC dan 1250oC. Kemudian diukur nilai bulk density dan porositas yang menunjukkan kondisi optimum berada pada suhu 1250oC. Sampel yang menunjukkan kondisi optimum dianalisis menggunakan XRD dan menunjukkan tidak terjadi perubahan fasa dan karakterisasi VSM menunjukkan sampel pada penambahan 1, 5 dan 9% wt adalah semi-hard magnetik dengan koersivitas 0,7 – 1,2 kOe dan dapat diaplikasikan sebagai sensor magnetic, hysteresis device dan telekomunikasi. Sedangkan pada penambahan 7% wt FeMo mampu menghasilkan hard-magnetik dan dapat diaplikasikan pada electric motors pada jam dan komputer, printers, galvanometer, lousdpeaker, microphone, dan Nuclear Magnetic Resonance (NMR).100 HalamanSkripsi Sarjan
Pengaruh Penambahan Fe terhadap Sifat Fisis dan Magnetik dari Barium Heksaferit (BaFe12O19)
No full textHas been syntesis permanent magnet barium hexaferrite (BaFe12-O19)) by the
addition of Fe particle through the integration of mechanical alloying using
shacker mill with 20 hour milling time. Variables research is dopping
concentration of Fe in barium hexaferrite (BaFe12O19) materials which obtained
by x = 0, 1, 5, 10, and 20% weight, and sintering temperature are 1100,1150, and
1200, with holding time for 1 hour. Quantities observed were an average particle
diameter size of the PSA, density, porosity, flux density, hysteresis curves,
microstructure analysis by XRD and SEM. From the observation of dilatometer
shows that the best sintering temperature is at 1150oC with holding time for 1
hours. Increasing the sintering temperature to 1200ºC with the addition of Fe
showed an increase in grain size and followed by decrease in magnetic
properties. Identification peak diffraction pattern material showed the formation
of the material before sintering not only single phase of BaFe12O19 but there are
also some new phase such as hematite (Fe2O3) and magnetite ( Fe3O4) then after
sintering process showed only one singgle phase is BaFe12O19. SEM-EDX
analysis of the obtained materials atomic percent increase to 34.64 and morfologi
of barium heksaferit is hexagonal shaped with diameters ranging ≤ 2 μm. PSA
analysis shows the average distribution of particle diameters ranging from 0.2 to
15 m and relatively dense with a porosity of <15% μm.BaFe12O19 magnetic
materials is relatively dense with a porosity of < 15 %, bulk density ranges from
4.46 – 4.89 g/cm3, flux density magnetic value is around 505,4 – 883,3 gauss and
coercivity range from 1,296-3,479 kOe. The addition of Fe in optimum
proportions with optimum sintering time on the magnetic barium hexaferrite can
increase the value of magnetic barium hexaferrite The best composition is the
addition of 1 wt % Fe that produces 3.479 kOe coercivity and flux density 883.3
Gauss.Telah dilakukan sintesis magnet permanen barium heksaferit (BaFe12O19) dengan
penambahan imbuhan Fe melalui teknik pemaduan mekanik (mechanical
alloying) menggunakan shacker mill yang berlangsung selama 20 jam
miling.Variabel penelitian adalah konsentrasi imbuhan Fe dengan x = 0, 1, 5, 10,
20% berat serta suhu sintering dengan variasi suhu 1100,1150,dan 12000C yang
masing-masing ditahan selama 1 jam. Besaran-besaran yang diamati meliputi ratarata
diameter partikel dengan PSA, analisa suhu terbaik dengan dilatometer,
densitas, porositas, fluks densitas, kurva histerisis dan analisa mikrostruktur
dengan XRD dan SEM. Dari hasil pengamatan dilatometer menunjukkan bahwa
suhu sintering terbaik adalah pada 1150oC. Peningkatan suhu sinter sampai
1200ºC dengan penambahan Fe menunjukkan peningkatan ukuran grain serta
diikuti dengan penurunan sifat kemagnetannya. Identifikasi puncak pola difraksi
bahan sebelum sintering menunjukkan adanya fasa baru selain fasa BaFe12O19
yaitu fasa hematit (Fe2O3) dan magnetit (Fe3O4) tetapi setelah proses sintering
berlangsung hanya ada fasa tunggal BaFe12O19. Dari analisa SEM-EDX diperoleh
persen atomik bahan meningkat hingga 34,64 % atomik dan morfologinya
berbentuk heksagonal dengan diameter berkisar ≤ 2 μm. Analisa PSA
menunjukkan rata-rata distribusi diameter partikel berkisar 0,2-15 μm serta relatif
padat dengan porositas < 15 %. Bulk density berkisar 4,46 –4,89 g/cm3 dan fluks
densitas magnetik berkisar 505,4 – 883,3 Gauss. Nilai koersivitas bahan berkisar
1,296-3,479 kOe. Penambahan logam Fe pada proporsi yang optimum dengan
waktu sintering optimum pada magnet barium heksaferit berhasil meningkatkan
nilai kemagnetan barium heksaferit. Komposisi terbaik adalah pada penambahan
imbuhan Fe 1% wt yang menghasilkan koersivitas 3,479 kOe dan fluks densitas
883,3 Gauss.153 HalamanTesis Magiste
The Effect of Fe3O4 Composition on Peg 6000-Resin Damar Based Phase Change Materials
No full textPhase change material (PCM) compositions based on PEG 6000, Fe3O4, resin, and
SDBS by sonication method at 80 ° C frequency 40 kHz was prepared. The
composition variations of the mass used are 2%Damar : 98%PEG6000, 2%Fe3O4 :
1%SDBS : 2%Damar : 95%PEG6000, 4% Fe3O4 : 2%SDBS : 2%Damar : 92%
PEG6000, dan 6%Fe3O4 : 3%SDBS : 2%Damar : 89%PEG6000. This research was
conducted to determine the effect of composition variation F3O4 , the thermal and
physical characteristics of PCM, and to determine the optimum composition of PCM.
DSC thermal characterization results Fe3O4 with the addition of having the greatest
enthalpy value of 205.25 J/g. Thermal conductivity characterization results have the
highest conductivity in 0.36 W/mK. And the results of TGA characteristics started to
be degraded at a temperature of 189.16C and a mass loss of 94.36%. The physical
characterization results of PCM with XRD analysis, the pattern of the graph shows a
tetragonal crystal structure on PEG 6000-resin and for the addition Fe3O4 has a
cubic crystal structure. The results of density testing increased with the addition of
Fe3O4 . The most optimum composition concentration based on thermal distribution
analysis is in the composition of PCM 2%Fe3O4 : 1%SDBS : 2%Damar :
95%PEG6000.62 PagesSkripsi Sarjan
The Effect of Al2O3 Composition on Peg-6000 Based Phase Change Materials
No full textPhase Change Material (PCM) research has been conducted by mixing PEG 6000 - Alumina Oxide (Al2O3) - Sodium Dodecyl Benzene Sulfonate as a Thermal Energy Storage (TES) application. This research is intendent to produce the best PCM with the effect of Al2O3 addition by sonication method. PCMs were characterised to determine their thermal properties (DSC, Thermal conductivity, and TGA) and physical properties (XRD and SEM-EDX). DSC test results show that with the addition of Al2O3, the latent heat enthalpy value decreases but the PCM thermal conductivity test results increase. In addition, in the TGA test, it was found that the working efficiency of the PCM material was up to 282.26℃ in the 88%PEG 6000+8%Al2O3+4%SDBS sample. SEM-EDX results showed that Al2O3 nanoparticles were not evenly distributed in the PEG 6000 structure. XRD results of the 82%PEG 6000+12%Al2O3+4%SDBS sample showed no addition of new phases. Density results obtained PCM composite density value increases along with the addition of Al2O3. In this study, the best PCM sample was obtained with the addition of 88%PEG 6000+8%Al2O3+4%SDBS composition. So that PCM can be applied in building air conditions, textiles, protection in the transportation of temperature-sensitive products, and others.71 PagesSkripsi Sarjan
Pembuatan Magnet Permanen Barium Heksaferit dengan Subsitusi Ion Mn dan Ti pada Ion Fe sebagai Material Penyerap Gelombang Mikro
No full textHas been made permanent magnet based on BaFe12-2x)MnxTixO19 from
technical grade materials of barium carbonate (BaCO3), hematite (Fe2O3),
manganese oxide (MnO) and titanium oxide (TiO2) by solid state reaction method.
Variables of the research is doping concentration of Mn and Ti ions performed for
substituting of Fe ion in barium hexaferrite (BaFe12O19) materials which obtained
by x = 0.1, 0.2, 0.3, 0.4, 0.5 and 0.6% mole, and the sintering temperature of
1000, 1050, 1100, 1150, 1200, and 1250oC with holding time of 2 hours.
Quantities observed were include porosity, density, flux density, hysteresis curves,
microstructure analysis by XRD, SEM, and μXRF and the material absorption test
by using VNA. From the observations indicate that the best calcination and
sintering temperature is 1000oC and 1100oC with holding time for 2 hours.
Doping Mn-Ti ions as a partial substitute Fe ion produce a single structure
BaFe12O19 with lattice parameters a = b = 5,892 Å, c = 23 183 Å and V = 696
404 Å3, and the morphology is relatively homogeneous with the particle shape
resembles a rod with a particle size < 2 μm. The BaFe(12-2x)MnxTixO19 magnetic
materials is relatively dense with a porosity of < 0.2%, bulk density ranges from
3.66 – 4.18 g/cm3, the flux density magnetic value is a round 36.7 - 488 Gauss,
remanensi Br < 1.25 kGauss, coercivity HCB < 1kOe and BHmax < 0.7MGOe. The
BaFe(12-2x)MnxTixO19 magnetic materials has been made was given permeability
values wich can be responsibility of microwave frequencies, especially at 0.6%
mole Mn-Ti ions and in the frequency range is a round 4.3 – 4.33, and 8.85 GHz.
The value of permittivity of that materials also has a particularly good respons at
the frequency a round: 5 – 5.05, 5.92 - 5.95, 8.7 and 9.94 GHz. Reflection loss, RL
is the best composition of Mn-Ti ions dopant at 0.4, 0.1 and 0.2% mole is equal to
-25.6, -22.2 and -23.2dB, at frequency 7.9 and 9.1GHz respectively, and able to
absorb > 90%, especially in the frequency range 4.75 - 4.96, 5.77 - 5.80, 8.02 to
8.05 and 9.07 - 9. 13 GHz.Telah dibuat magnet permanen berbasis BaFe(12-2x)MnxTixO19 dari bahan baku
barium carbonate (BaCO3), hematite (Fe2O3), manganese oxide (MnO) dan
titanium oxide (TiO2) melalui reaksi padatan. Variabel penelitian yang dilakukan
adalah kosentrasi doping ion Mn dan Ti sebagai subsitusi ion Fe pada bahan
barium hexaferrite (BaFe12O19) dengan x = 0.1, 0.2, 0.3, 0.4, 0.5 dan 0.6% mol,
serta suhu sintering 1000, 1050, 1100, 1150, 1200, dan 1250oC yang masingmasing
ditahan selama 2 jam. Besaran-besaran yang diamati meliputi porositas,
densitas, fluks densitas, kurva histerisis, analisa mikrostruktur dengan XRD,
SEM, dan μXRF serta uji absorpsi material tersebut dengan menggunakan VNA.
Dari hasil pengamatan menunjukkan bahwa suhu kalsinasi dan sintering yang
terbaik adalah 1000oC dan 1100oC masing-masing ditahan 2 jam. Doping ion Mn-
Ti sebagai subsitusi sebagian ion Fe menghasilkan struktur tunggal BaFe12O19
dengan parameter kisi a = b = 5.892 Å, c = 23.183 Å dan V = 696.404 Å3, dan
morfologinya relatif homogen dengan bentuk partikel menyerupai batang dengan
ukuran partikel < 2 μm. Magnet BaFe(12-2x)MnxTixO19 relatif padat dengan
porositas < 0.2%, bulk density berkisar 3.66 – 4.18 g/cm3, fluks density magnetik
berkisar 36.7 – 488 Gauss, remanensi Br < 1.25 kGauss, koersivitas HCB < 1kOe
dan BHmax < 0.7MGOe. Material magnetik BaFe(12-2x)MnxTixO19 yang dibuat
menghasilkan nilai permeability yang dapat merespon gelombang micro terutama
pada 0.6% mol ion Mn-Ti dan daerah frekuensi sekitar 4.3 – 4.33, dan 8.85 GHz.
Dari nilai permittivity material ini juga memiliki respon yang baik terutama untuk
daerah frekuensi 5 – 5.05, 5.92 – 5.95, 8.7 dan 9.94 GHz. Reflection loss, RL
komposisi terbaik adalah pada doping 0.4, 0.1 dan 0.2% mol ion Mn-Ti yaitu
sebesar -25.6,-22.2 dan -23.2dB masing-masing pada frekuensi 7.9 dan 9.1GHz,
serta mampu menyerap > 90%, terutama pada daerah frekuensi 4.75 – 4.96, 5.77 –
5.80, 8.02 – 8.05 dan 9.07 – 9. 13 GHz.140 Halama
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