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Abstrak :
ABSTRAK
Baja ODS (Oxide Dispersion Strengthened) merupakan paduan dengan ketahanan temperatur dan korosi yang baik. Penggunaan metode iradiasi ultrasonik di dalam larutan toluene merupakan metode baru yang dapat memberikan keuntungan berupa ukuran butir yang halus, dapat membentuk microalloying di dalam serbuk, dan dapat meminimalisasi pembentukan fasa oksida. Penelitian ini mempelajari tentang pengaruh amplitudo terhadap reduksi ukuran partikel, homogenitas serbuk, dan pembentukan microalloying Fe-Cr pada preparasi serbuk Fe-15Cr-0.5Y2O3. Serbuk dibagi menjadi 4 sampel dengan perlakuan pencampuran mortar (sampel A), iradiasi ultrasonik dengan amplitudo 40% (sampel B), 50% (sampel C), dan 60% (sampel D) yang kemudian dikarakterisasi menggunakan SEM, EDS, dan XRD. Hasil dari penelitian ini adalah peningkatan amplitudo akan menurunkan ukuran butir dengan nilai sampel B>sampel C>sampel D adalah 4.63 μm>3.44 μm>3.09 μm. Sampel C menghasilkan partikel Fe-Cr sementara sampel B dan D terbentuk partikel paduan Fe-Cr-Y2O3. Nilai komposisi Fe-Cr terbesar dicapai pada amplitudo 40% dengan nilai sampel A:sampel B:sampel C: sampel D adalah 0.00%:20.5%:10.06%:5.2% tanpa pembentukan oksida dengan ukuran crystallite Fe-Cr sampel B:sampel C:sampel D berukuran 16.79 nm:30.13 nm: 55.69 nm. Nilai lattice strain sampel B:sampel C: sampel D adalah 0.0055:0.0030:0.0016.

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ABSTRACT
ODS Steel (Oxide Dispersion Strengthened) is an alloy with good corrosion and high temperature resistance. The utilization of ultrasonic irradiation method in toluene solution is a new method giving benefits like producing fine grain-size, forming micro-alloying on powder, and minimizing the oxide phase formation. This research investigates the influence of amplitude on the reduction of the particle size, the homogeneity of the powder, and the formation of Fe-Cr microalloying on Fe-15Cr-0.5Y2O3 powder preparation. The powder was divided into 4 samples with various treatments such as mortar mixing (sample A) and ultrasonic irradiation with an amplitude of 40% (sample B), 50% (sample C) and 60% (sample D). After that, each sample was characterized by SEM, EDS and XRD. This research shows that increasing the amplitude will decrease the grain size with the value of sample B> sample C> sample D is 4.63 μm>μm 3:44> 3:09 μm. Sample C produced Fe-Cr particles meanwhile samples B and D formed Fe-Cr-Y2O3 alloy particle. The highest composition value of Fe-Cr is reached on the amplitude of 40% to the composition value of sample A: sample B: sample C: sample D is 0.00%: 20.5%: 10:06%: 5.2% without the oxide formation. The size of crystalline Fe-Cr sample B: sample C : sample D size of 16.79 nm: 30.13 nm: 55.69 nm. The lattice strain value of the sample B: the sample C: sample D was 0.0055: 0.0030: 0.0016. ;

Abstrak :
In this work the formation of Fe-Cr microalloy by ultrasonic irradiation at a frequency of 20 kHz is presented. Two sample series were produced with different ultrasonic irradiation procedures. For the first sample, Fe and Cr powder were each separately brought into the ultrasonic device before they were mixed in 7:1 weight ratio and then together retreated using the ultrasonic method. Secondly, Fe and Cr powder with same weight ratio were mixed and directly ultrasonically irradiated. During the ultrasonic irradiation process both samples were put in a toluene solution of 99%. The formation of the Fe-Cr microstructure in conjunction with ultrasonication time were investigated by using Scanning Electron Microscopy (SEM ), X-ray Diffraction (XRD) and Transmission Electron Microscopy (TEM). After 40 hours of ultrasonic irradiation the particle sizes of the Fe powder of the first samples became significantly smaller; some particles were also fused together. However, with the exception of smaller-sized particles no fused Cr powders can be found even after 63 hours of ultrasonic irradiation. After both experiments Fe and Cr were mixed and again ultrasonically irradiated for 20 hours. Some particles indicated as Fe-Cr alloys containing 24.34 wt.% Fe and 67.43 wt.% Cr were observed. In the sample produced from the second procedure in which both Fe and Cr powders were irradiated together by an ultrasonic method for 50 hours, some powder particles formed a Fe-Cr microalloy with the composition of 96.27 wt.% Fe and 3.73 wt.% Cr. The XRD analysis revealed that the Fe-Cr alloy from the first samples has a BCC structure with a mass fraction of Fe:Cr:Fe-Cr which is equal to 0.836:0.0294:0.135, while the mass fraction of the Fe-Cr alloy from the second sample series is equal to 0.736:0.0808:0.183, respectively. Analysis of the TEM selected area diffraction patterns (SAED) confirmed that the Fe-Cr microalloy occured originaly from the precursor Fe and Cr particles of size smaller than 2 µm. The Fe-Cr microalloy has been successfully synthesized by using an ultrasonic process.

Abstrak :
ABSTRAK
Percampuran serbuk baja ODS Oxide Dispersion Strengthened pada umumnya menggunakan metode mekanik dengan ball mill, namun selama pembuatannya disertai pembentukan oksida. Percampuran serbuk dengan metode iradiasi ultrasonik merupakan metode baru yang memberikan keuntungan berupa membentuk microalloying partikel dan meminimalisasi pembentukan fasa oksida. Penelitian ini mempelajari tentang pengaruh amplitudo 20, 30, 40 dan waktu perlakuan 20jam, 30 jam terhadap reduksi ukuran partikel dan pembentukan microalloying Fe-Cr. Serbuk dibagi menjadi 7 sampel dengan sampel A perlakuan pencampuran mortar, iradiasi ultrasonik sampel B1 A:20, t: 20 jam, sampel B2 A:30, t:20 jam, sampel B3 A:40, t:20 jam, sampel C1 A:20, t:30 jam, sampel C2 A:40, t:30 jam, dan sampel C3 A:40, t:30 jam yang kemudian dikarakterisasi menggunakan SEM, EDS, dan XRD. Hasil penelitian ini adalah pada iradiasi ultrasonik selama 20 jam menghasilkan ukuran partikel sampel B1>sampel B2>sampel B3 adalah 5.326 m>4.769 m>4.563 m. Sedangkan pada iradiasi ultrasonik selama 30 jam menghasilkan ukuran partikel sampel C1>sampel C2>sampel C3 adalah 4.605 m>3.719 m>3.608 m. Komposisi Fe-Cr yang terbentuk adalah sampel A: sampel B1: sampel B2: sampel B3:sampel C1:sampel C2: C3 adalah 0:48.85:26.07:2478:89:81.94:42.98. Hasil tersebut menunjukan bahwa semakin besar amplitudo, microalloying Fe-Cr yang terbentuk menjadi semakin rendah, penambahan waktu perlakuan justru meningkatkan presentase Fe-Cr yang terbentuk. Pada ultrasonik selama 20 jam, nilai crystallite size Fe-Cr sampel B1>sampel B2>sampel B3 adalah 292.72 nm>246.76 nm>184.77 nm dan nilai microstrains Fe-Cr sampel B1184.34 nm dan nilai microstrains Fe-Cr sampel C1< sampel C2.

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ABSTRACT
The mixing of ODS Oxide Dispersion Strengthened powder generally uses mechanical method with ball mill, but during its manufacture with oxide formation. Powder mixing with ultrasonic irradiation method is a new method that provides the advantage of forming microalloying particles and minimizing the formation of the oxide phase. This study studied the effect of amplitude 20, 30, 40 and treatment time 20h, 30h on particle size reduction and formation of Fe Cr microalloying. The powder was divided into 7 samples with sample A mortar mixing treatment, ultrasonic irradiation of sample B1 A 20, t 20 hours, sample B2 A 30, t 20 hours, sample B3 A 40, T 20 hours, sample C1 A 20, t 30 hours, C2 sample A 40, t 30 hours, and C3 sample A 40, t 30 hours Which is then characterized using SEM, EDS, and XRD. The results of this study were on ultrasonic irradiation for 20 hours yielding sample particle size B1 sample B2 B3 sample was 5,326 m 4,769 m 4,563 m. While on ultrasonic irradiation for 30 hours resulted in particle size of sample C1 C2 sample C3 sample is 4,605 m 3,719 m 3,608 m. The composition of Fe Cr formed is sample A sample B1 sample B2 sample B3 sample C1 sample C2 C3 is 0 48.85 26.07 24.78 89 81.94 42.98. These results show that the greater the amplitude, the lower the Fe Cr microalloying that is formed, the added time of treatment actually increases the Fe Cr percentage that is formed. At ultrasonic for 20 hours, the crystallite size of Fe Cr sample B1 sample B2 B3 sample is 292.72 nm 246.76 nm 184.77 nm and the Fe Cr microstrains value of sample B1 198.02 nm 184.34 nm and the Fe Cr microstrains value of sample C1.

Abstrak :
Nanoalloys : from fundamentals to emergent applications presents and discusses the major topics related to nanoalloys at a time when the literature on the subject remains scarce. Particular attention is paid to experimental and theoretical aspects under the form of broad reviews covering the most recent developments. The book is organized into 11 chapters covering the most fundamental aspects of nanoalloys related to their synthesis and characterization, as well as their theoretical study. Aspects related to their thermodynamics and kinetics are covered as well. The coverage then moves to more specific topics, including optics, magnetism and catalysis, and finally to biomedical applications and the technologically relevant issue of self-assembly. With no current single reference source on the subject, the work is invaluable for researchers as the nanoscience field moves swiftly to full monetization.