This paper describes the results of studies carried out on bulk amorphous materials with the chem... more This paper describes the results of studies carried out on bulk amorphous materials with the chemical compositions: Fe 61+x Co 10−x Y 8 W 1 B 20 (where x = 0, 1 or 2). The alloy samples were produced in the form of plates with the following dimensions: 10 mm × 5 mm × 0.5 mm. Massive amorphous glass structures were produced by two methods: injection and suction casting. On the basis of the recorded X-ray diffraction patterns, only the disordered phase was identified within the volume of each alloy. The only exception was the alloy with the chemical composition: Fe 62 Co 9 Y 8 W 1 B 20 , produced by the injection method, in the volume of which an (insignificant) trace quantity of the Fe 5 Y phase was registered. The presence of this phase explains the lower value of the coercive field compared to the other alloys. The investigations confirmed the effect of the cobalt content on the coercive field value, and the Curie temperature, of the amorphous alloys. However, the cobalt content was not found to have a significant influence on the saturation of magnetisation. Also, the method of producing the investigated amorphous materials does not seem to have a significant effect on the magnetic properties of the resulting alloys.
Abstract Dynamic magnetic susceptibilities of high-aspect-ratio permalloylike nanorings (outer di... more Abstract Dynamic magnetic susceptibilities of high-aspect-ratio permalloylike nanorings (outer diameter 20 nm, inner diameter 12 nm, length (L) range 12–500 nm) are studied using three-dimensional micromagnetic simulations. The investigated systems show two ...
ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika
ABSTRAKAntena mikrostrip double E-shaped untuk aplikasi WiMax melalui proses simulasi dan fabrika... more ABSTRAKAntena mikrostrip double E-shaped untuk aplikasi WiMax melalui proses simulasi dan fabrikasi telah berhasil dirancang. Perancangan desain antena mikrostrip ini menggunakan bahan substrat FR-4 lossy dengan ketebalan 1,6 mm dan konstanta dielektrik 4,6. Dimensi substrat yang dirancang yaitu 45 mm x 52 mm x 1,6 mm. Hasil simulasi yang diperoleh yaitu antena mikrostrip bekerja di frekuensi 3,3 GHz, return loss -21 dB, VSWR 1,23, bandwidth 342 MHz, dan gain sebesar 3,5 dBi. Hasil pengukuran diperoleh antena mikrostrip bekerja di frekuensi 3,35 GHz, return Loss -22 dB, VSWR 1,26, bandwidth 265 MHz, dan gain sebesar 3,2 dBi. Baik hasil simulasi dan pengukuran pola radiasi yang dihasilkan membentuk pola bidirectional. Antena mikrostrip ini dapat diaplikasikan pada frekuensi Wimax.Kata kunci: Antena Mikrostrip, Double E-shaped, Frekuensi 3,3 GHz, WiMax, Return Loss ABSTRACTThe double E-shaped microstrip antenna for WiMax application through simulation and fabrication process has been ...
Abstract- The oscillation domain wall (DW) was studied at Co nanowire. It is consist of a symmetr... more Abstract- The oscillation domain wall (DW) was studied at Co nanowire. It is consist of a symmetry notches such as arc, triangular and rectangular with the dimension of 2000×200×5 nm3. The micromagnetic simulation based on the Landau-Lifshitz-Gilbert was performed by using AC magnetic field along the wire axis at constant amplitude 2 mT,frequency from 0.3 to 2.0 GHz, and damping constant 0.01. It was found that DW oscillation occurred on all type of notches at the same frequency. However, it’s shown that the DW oscillation in rectangular notch generate amplitude. It can be seen that the amplitudo of DW decreases as the applied field increases, furthermore, phase difference between the applied field and the DW position increases as the frequency increases. Index Term-- Co nanowire, oscillation domain wall, micro-magnetic simulation, symmetric notch I.
The concentration and wavelength-dependent refractive index of sugar solution have been determine... more The concentration and wavelength-dependent refractive index of sugar solution have been determined using Sellmeier Equation. The equations describe the refractive index as a function of wavelength parameter. They could be generalized as a function of material concentration by investigating the characteristic of their Sellmeier constants A and B. The three wavelengths used to identify the refractive index of sugar solutions were 455 nm, 525 nm, and 633 nm, while the concentration of the sugar solution ranged from 0 to 40%. This paper reported in this research performed the empirical expression of concentration-dependent of the sugar solution. The A and B Sellmeier constants were the main subjects to be concerned. A constant has a linear relationship with the sugar solution at 15% concentration to 40%. Under a concentration of 15%, the refractive index is quadratic towards engagement. The sellmeier B constant has a quadratic relation characteristic below the attention of 15%. Above 15...
Computational And Experimental Research In Materials And Renewable Energy, 2019
A hard disk is a data storage medium composed of a thin layer of magnetic material. Hard drives t... more A hard disk is a data storage medium composed of a thin layer of magnetic material. Hard drives take advantage of the characteristics of magnetic materials that are stable to heat and have sensitivity to magnetic fields. One of the best materials to use a thin layer ferromagnetic on a hard disk is CoNi alloy. Hard drives with larger storage capacities require magnetic materials with high magnetic susceptibility values and Curie temperatures to obtain the best magnetic properties. The magnetic susceptibility of alloy ferromagnetic material Co (1- x) Ni (x) nanocube and nanosphere is calculated using vampire-based micro magnetic simulation. The research was conducted using a literature review on the parameters of the CoNi alloy material, and then it was simulated in the vampire program. The data generated from the simulation are magnetic susceptibility (1/tesla) and temperature (K). The spectrum of the magnetic susceptibility graph that shifts to the right as the Ni (x) composition de...
Computational And Experimental Research In Materials And Renewable Energy, 2020
Fe3O4 is the strongest magnet among other iron oxides. Magnetite Fe3O4 is applied as a permanent ... more Fe3O4 is the strongest magnet among other iron oxides. Magnetite Fe3O4 is applied as a permanent magnet. The hysteresis curve of the permanent magnet Fe3O4 has a coercivity field that is not too large so that the material has a good chance to be applied as an absorbent material for RADAR waves. Micromagnetic simulations were carried out on Fe3O4 material in the form of thin film against hysteresis curves and ferromagnetic resonances at various thickness variations and side length variations, and the relationship was seen with changes in the bandwidth of the radar wave absorption frequency if the thickness variation of the simulated material had the same multiple as the experimental material. The thickness variations in this study were 60 nm, 90 nm, and 120 nm, where the variations in the experiment were 0.6 mm, 0.9 mm, and 1.2 mm. Micromagnetic simulation runs were performed to obtain the hysteresis curve and resonance frequency of the Fe3O4 material. The simulation results show tha...
Computational And Experimental Research In Materials And Renewable Energy, 2020
The lift force is one of the important factors in supporting the aircraft flying capabilities. Th... more The lift force is one of the important factors in supporting the aircraft flying capabilities. The airplane has a section called the aircraft wing. In particular, the wing section of aircraft is called the airfoil. One of the efforts to increase the lift force is to make the flow of air fluid at the top of the airfoil more turbulent. Turbulent flow can attract momentum from the boundary layer, the result of this momentum transfer has energy that is more resistant to the adverse pressure gradient which can trigger the flow separation. Efforts that can be made to reduce separation flow and increase lift force are the addition of a turbulent generator on the upper surface of the airfoil, one type of turbulent generator is a vortex generator, a vortex generator can accelerate the transition from the laminar boundary layer to the turbulent boundary layer. This study was conducted with the aim of knowing the effect of the vortex generator on the aerodynamics of NACA-4412 using the computa...
Computational And Experimental Research In Materials And Renewable Energy, 2018
Composite materials (GRE pipe) had been applied in various industries. These kind application are... more Composite materials (GRE pipe) had been applied in various industries. These kind application are based on the advantages of composite properties, that are lightweight, high corrosion resistance and low cost. In order to make a lightweight and strong materials, some materials that light and stiff had been widely used, lie fiber glass, epoxy and the other. These materials (fiber glass and epoxy) are synthetic and non-biodegradable, but give some advantages in composite to make composite more stiff, light and strong. Mechanical properties of fiber glass composites had been doing based on theory through modeling. Theoretical results obtained showed that maximum stress and shear modulus value of GRE pipe are less than each components (glass fiber and epoxy resin). Each value of maximum stress and shear modulus are 584,57 MPa and 46,15 MPa.
Material Kobalt Nikel (CoNi) merupakan paduan penting karena memiliki sifat kemagnetan yang baik ... more Material Kobalt Nikel (CoNi) merupakan paduan penting karena memiliki sifat kemagnetan yang baik diantaranya yaitu temperatur curie dan koersivitas yang tinggi. komposisi, struktur alloy dan ukuran sisi kubus bahan berpengaruh terhadap temperatur Curie dan koersivitas. Simulasi mikromagnetik dilakukan pada material Co 0 ,8 Ni 0 ,2 dengan struktur random alloy dan double layers untuk menentukan nilai temperatur Curie dan analisis kurva histerisis. Simulasi material Co 0 ,8 Ni 0 ,2 dilakukan menggunakan software Vampire dengan variasi ukuran sisi kubus yang digunakan yaitu 5 nm, 8 nm, 10 nm, 12 nm, dan 15 nm. Hasil simulasi menunjukkan nilai temperatur Curie semakin meningkat dengan bertambahnya ukuran sisi kubus. Pada material Co 0 ,8 Ni 0 ,2 double layers diperoleh nilai temperatur Curie lebih tinggi dari pada material Co 0 ,8 Ni 0 ,2 random alloy . Karakteristik kurva histerisis pada material Co 0 ,8 Ni 0 ,2 random alloy dan double layers menunjukkan bahwa nilai koersivitas meningk...
Platinum (FePt) is a ferromagnetic material that has a Face Centered Cubic (FCC) crystal structur... more Platinum (FePt) is a ferromagnetic material that has a Face Centered Cubic (FCC) crystal structure. FePt material is classified as a hard magnetic material that can be applied as a magnetic storage medium. The composition of the material used in this study was Fe0.85Pt0.15. This study examined the magnetic properties of nano-sphere shaped FePt materials against the coercivity fields under the effect of heat-assisted variations in laser power values. The difference in magnetic properties due to the influence of laser power was seen based on the hysteresis curve. Micro-magnetic simulations were carried out to obtain Curie-temperature values, hysteresis curves, and configuration of the direction of spin of FePt material. This simulation found the Curie-temperature of the material as 650 K. The direction of the magnetization reversed by the power laser-assisted so quickly. With a small coercivity field; magnetic recording media can carry out the writing and recording process in high cap...
This paper describes the results of studies carried out on bulk amorphous materials with the chem... more This paper describes the results of studies carried out on bulk amorphous materials with the chemical compositions: Fe 61+x Co 10−x Y 8 W 1 B 20 (where x = 0, 1 or 2). The alloy samples were produced in the form of plates with the following dimensions: 10 mm × 5 mm × 0.5 mm. Massive amorphous glass structures were produced by two methods: injection and suction casting. On the basis of the recorded X-ray diffraction patterns, only the disordered phase was identified within the volume of each alloy. The only exception was the alloy with the chemical composition: Fe 62 Co 9 Y 8 W 1 B 20 , produced by the injection method, in the volume of which an (insignificant) trace quantity of the Fe 5 Y phase was registered. The presence of this phase explains the lower value of the coercive field compared to the other alloys. The investigations confirmed the effect of the cobalt content on the coercive field value, and the Curie temperature, of the amorphous alloys. However, the cobalt content was not found to have a significant influence on the saturation of magnetisation. Also, the method of producing the investigated amorphous materials does not seem to have a significant effect on the magnetic properties of the resulting alloys.
Abstract Dynamic magnetic susceptibilities of high-aspect-ratio permalloylike nanorings (outer di... more Abstract Dynamic magnetic susceptibilities of high-aspect-ratio permalloylike nanorings (outer diameter 20 nm, inner diameter 12 nm, length (L) range 12–500 nm) are studied using three-dimensional micromagnetic simulations. The investigated systems show two ...
ELKOMIKA: Jurnal Teknik Energi Elektrik, Teknik Telekomunikasi, & Teknik Elektronika
ABSTRAKAntena mikrostrip double E-shaped untuk aplikasi WiMax melalui proses simulasi dan fabrika... more ABSTRAKAntena mikrostrip double E-shaped untuk aplikasi WiMax melalui proses simulasi dan fabrikasi telah berhasil dirancang. Perancangan desain antena mikrostrip ini menggunakan bahan substrat FR-4 lossy dengan ketebalan 1,6 mm dan konstanta dielektrik 4,6. Dimensi substrat yang dirancang yaitu 45 mm x 52 mm x 1,6 mm. Hasil simulasi yang diperoleh yaitu antena mikrostrip bekerja di frekuensi 3,3 GHz, return loss -21 dB, VSWR 1,23, bandwidth 342 MHz, dan gain sebesar 3,5 dBi. Hasil pengukuran diperoleh antena mikrostrip bekerja di frekuensi 3,35 GHz, return Loss -22 dB, VSWR 1,26, bandwidth 265 MHz, dan gain sebesar 3,2 dBi. Baik hasil simulasi dan pengukuran pola radiasi yang dihasilkan membentuk pola bidirectional. Antena mikrostrip ini dapat diaplikasikan pada frekuensi Wimax.Kata kunci: Antena Mikrostrip, Double E-shaped, Frekuensi 3,3 GHz, WiMax, Return Loss ABSTRACTThe double E-shaped microstrip antenna for WiMax application through simulation and fabrication process has been ...
Abstract- The oscillation domain wall (DW) was studied at Co nanowire. It is consist of a symmetr... more Abstract- The oscillation domain wall (DW) was studied at Co nanowire. It is consist of a symmetry notches such as arc, triangular and rectangular with the dimension of 2000×200×5 nm3. The micromagnetic simulation based on the Landau-Lifshitz-Gilbert was performed by using AC magnetic field along the wire axis at constant amplitude 2 mT,frequency from 0.3 to 2.0 GHz, and damping constant 0.01. It was found that DW oscillation occurred on all type of notches at the same frequency. However, it’s shown that the DW oscillation in rectangular notch generate amplitude. It can be seen that the amplitudo of DW decreases as the applied field increases, furthermore, phase difference between the applied field and the DW position increases as the frequency increases. Index Term-- Co nanowire, oscillation domain wall, micro-magnetic simulation, symmetric notch I.
The concentration and wavelength-dependent refractive index of sugar solution have been determine... more The concentration and wavelength-dependent refractive index of sugar solution have been determined using Sellmeier Equation. The equations describe the refractive index as a function of wavelength parameter. They could be generalized as a function of material concentration by investigating the characteristic of their Sellmeier constants A and B. The three wavelengths used to identify the refractive index of sugar solutions were 455 nm, 525 nm, and 633 nm, while the concentration of the sugar solution ranged from 0 to 40%. This paper reported in this research performed the empirical expression of concentration-dependent of the sugar solution. The A and B Sellmeier constants were the main subjects to be concerned. A constant has a linear relationship with the sugar solution at 15% concentration to 40%. Under a concentration of 15%, the refractive index is quadratic towards engagement. The sellmeier B constant has a quadratic relation characteristic below the attention of 15%. Above 15...
Computational And Experimental Research In Materials And Renewable Energy, 2019
A hard disk is a data storage medium composed of a thin layer of magnetic material. Hard drives t... more A hard disk is a data storage medium composed of a thin layer of magnetic material. Hard drives take advantage of the characteristics of magnetic materials that are stable to heat and have sensitivity to magnetic fields. One of the best materials to use a thin layer ferromagnetic on a hard disk is CoNi alloy. Hard drives with larger storage capacities require magnetic materials with high magnetic susceptibility values and Curie temperatures to obtain the best magnetic properties. The magnetic susceptibility of alloy ferromagnetic material Co (1- x) Ni (x) nanocube and nanosphere is calculated using vampire-based micro magnetic simulation. The research was conducted using a literature review on the parameters of the CoNi alloy material, and then it was simulated in the vampire program. The data generated from the simulation are magnetic susceptibility (1/tesla) and temperature (K). The spectrum of the magnetic susceptibility graph that shifts to the right as the Ni (x) composition de...
Computational And Experimental Research In Materials And Renewable Energy, 2020
Fe3O4 is the strongest magnet among other iron oxides. Magnetite Fe3O4 is applied as a permanent ... more Fe3O4 is the strongest magnet among other iron oxides. Magnetite Fe3O4 is applied as a permanent magnet. The hysteresis curve of the permanent magnet Fe3O4 has a coercivity field that is not too large so that the material has a good chance to be applied as an absorbent material for RADAR waves. Micromagnetic simulations were carried out on Fe3O4 material in the form of thin film against hysteresis curves and ferromagnetic resonances at various thickness variations and side length variations, and the relationship was seen with changes in the bandwidth of the radar wave absorption frequency if the thickness variation of the simulated material had the same multiple as the experimental material. The thickness variations in this study were 60 nm, 90 nm, and 120 nm, where the variations in the experiment were 0.6 mm, 0.9 mm, and 1.2 mm. Micromagnetic simulation runs were performed to obtain the hysteresis curve and resonance frequency of the Fe3O4 material. The simulation results show tha...
Computational And Experimental Research In Materials And Renewable Energy, 2020
The lift force is one of the important factors in supporting the aircraft flying capabilities. Th... more The lift force is one of the important factors in supporting the aircraft flying capabilities. The airplane has a section called the aircraft wing. In particular, the wing section of aircraft is called the airfoil. One of the efforts to increase the lift force is to make the flow of air fluid at the top of the airfoil more turbulent. Turbulent flow can attract momentum from the boundary layer, the result of this momentum transfer has energy that is more resistant to the adverse pressure gradient which can trigger the flow separation. Efforts that can be made to reduce separation flow and increase lift force are the addition of a turbulent generator on the upper surface of the airfoil, one type of turbulent generator is a vortex generator, a vortex generator can accelerate the transition from the laminar boundary layer to the turbulent boundary layer. This study was conducted with the aim of knowing the effect of the vortex generator on the aerodynamics of NACA-4412 using the computa...
Computational And Experimental Research In Materials And Renewable Energy, 2018
Composite materials (GRE pipe) had been applied in various industries. These kind application are... more Composite materials (GRE pipe) had been applied in various industries. These kind application are based on the advantages of composite properties, that are lightweight, high corrosion resistance and low cost. In order to make a lightweight and strong materials, some materials that light and stiff had been widely used, lie fiber glass, epoxy and the other. These materials (fiber glass and epoxy) are synthetic and non-biodegradable, but give some advantages in composite to make composite more stiff, light and strong. Mechanical properties of fiber glass composites had been doing based on theory through modeling. Theoretical results obtained showed that maximum stress and shear modulus value of GRE pipe are less than each components (glass fiber and epoxy resin). Each value of maximum stress and shear modulus are 584,57 MPa and 46,15 MPa.
Material Kobalt Nikel (CoNi) merupakan paduan penting karena memiliki sifat kemagnetan yang baik ... more Material Kobalt Nikel (CoNi) merupakan paduan penting karena memiliki sifat kemagnetan yang baik diantaranya yaitu temperatur curie dan koersivitas yang tinggi. komposisi, struktur alloy dan ukuran sisi kubus bahan berpengaruh terhadap temperatur Curie dan koersivitas. Simulasi mikromagnetik dilakukan pada material Co 0 ,8 Ni 0 ,2 dengan struktur random alloy dan double layers untuk menentukan nilai temperatur Curie dan analisis kurva histerisis. Simulasi material Co 0 ,8 Ni 0 ,2 dilakukan menggunakan software Vampire dengan variasi ukuran sisi kubus yang digunakan yaitu 5 nm, 8 nm, 10 nm, 12 nm, dan 15 nm. Hasil simulasi menunjukkan nilai temperatur Curie semakin meningkat dengan bertambahnya ukuran sisi kubus. Pada material Co 0 ,8 Ni 0 ,2 double layers diperoleh nilai temperatur Curie lebih tinggi dari pada material Co 0 ,8 Ni 0 ,2 random alloy . Karakteristik kurva histerisis pada material Co 0 ,8 Ni 0 ,2 random alloy dan double layers menunjukkan bahwa nilai koersivitas meningk...
Platinum (FePt) is a ferromagnetic material that has a Face Centered Cubic (FCC) crystal structur... more Platinum (FePt) is a ferromagnetic material that has a Face Centered Cubic (FCC) crystal structure. FePt material is classified as a hard magnetic material that can be applied as a magnetic storage medium. The composition of the material used in this study was Fe0.85Pt0.15. This study examined the magnetic properties of nano-sphere shaped FePt materials against the coercivity fields under the effect of heat-assisted variations in laser power values. The difference in magnetic properties due to the influence of laser power was seen based on the hysteresis curve. Micro-magnetic simulations were carried out to obtain Curie-temperature values, hysteresis curves, and configuration of the direction of spin of FePt material. This simulation found the Curie-temperature of the material as 650 K. The direction of the magnetization reversed by the power laser-assisted so quickly. With a small coercivity field; magnetic recording media can carry out the writing and recording process in high cap...
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