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SINTESIS PADUAN CO-CR MENGGUNAKAN METODE ULTRASONIK Silalahi, Marzuki; Rahayu, Dena Nadya; Sugeng, Bambang; Aziz, Ferhat; Sukaryo, Sulistioso Giat
Jurnal Sains Materi Indonesia Vol 19, No 3: APRIL 2018
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.17146/jsmi.2018.19.3.4500

Abstract

Paduan Co-Cr merupakan material tahan suhu tinggi dan tahan korosi. Penelitian ini bertujuan mensistesis serbuk paduan Co-Cr dengan metode ultrasonik, kemudian dilanjutkan dengan proses sintering dalam kapsul kaca kuarsa. Iradiasi ultrasonik yang digunakan pada frekuensi 20 kHz dan amplitudo 40 % dengan komposisi Co : Cr sebesar 80 : 20.Waktu perlakuan sonikasi adalah selama 0 jam, 3 jam, 6 jam, 12 jam, 24 jam, dan 48 jamdalam larutan etanol. Setelah sonikasi selama 48 jam, fasa FCC dari Co mulai bertransformasi menjadi fasa HCP. Perlakuan ultrasonik terhadap campuran Co-Cr juga memberikan efek pengurangan ukuran partikel. Parameter kisi serbuk setelah ultrasonikasi 48 jam adalah: untuk HCP-Co a = b = 0,25074 nmdan c = 0,40699 nm, untuk FCC-Co a = b = c = 0,35411nm, dan untuk BCC-Cr a=b=c=0.28827 nm. Perlakuan ultrasonik selama 48 jam menhasilkan pembentukan paduan Co-Cr dengan persentasi berat sebesar 25,2124. Hasil sintering padatan Co-Cr menunjukkan parameter kisi HCP-Co memiliki nilai yaitu a = b = 0,25230 nm dan c=0,41223 nm, dan FCC-Co a = b = c = 0,35232 nm. Terbentuknya microalloying CoCr diindikasikan dari hasil EDS, teramati partikel yang mempunyai komposisi Co : Cr = 71,25 : 24,45. Paduan Co-Cr yang terbentuk setelah sintering pada 1300 oC adalah sebesar 15,33416 %berat.
MICROSTRUCTURE OF OXIDE DISPERSION STRENGTHENED STEEL WITH CR CONTENT VARIATION Silalahi, Marzuki; Bandriyana, Bernadus; Dimyati, Arbi; Sugeng, Bambang; Ahda, Syahfandi; N, Fitria
Jurnal Sains Materi Indonesia Vol 21, No 1: OCTOBER 2019
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1288.633 KB) | DOI: 10.17146/jsmi.2019.21.1.5590

Abstract

Microstructure and phase distribution of innovative Oxide Dispersion Strengthened (ODS) steel based on Fe-Cr-ZrO2 particularly for application at high temperature reactor with variation of Cr content was analysed. The alloy was synthesized with Cr composition variation of  15, 20 and 25 wt.% Cr, while zirconia dispersoid kept constant at 0.50 wt.%. The samples was synthesized by mechanical alloying comprising of high energy milling for 3 hours followed by vibrated compression with iso-static load at 20 ton. The final consolidation was performed via sintering process for 4 minutes using the Arc Plasma Sintering (APS) technique, a new method developed in BATAN especially for synthesizing high temperature materials. The samples were then characterized by means of scanning electron microscopy (SEM) with energy dispersed X-ray (EDX) analysis capability and X-ray diffraction. The mechanical property of hardness was measured using standard Vickers micro hardness tester to confirmed the microstructure analysis.  The results show that the microstructure of the ODS alloy samples in all variation of Cr content consists generally of cubic Fe-Cr matrix phase with small of porosity and  Zirconia particles distributed homogenously in and around the matrix grains. The achievable hardness was between 142 and 184 HVN dependent consistently on Cr content in which Cr element may cause grain refining that in turn increase the hardness.
Synthesis and Corrosion Test of Magnesium Zinc-5% Hydroxyapatite (MgZn-5% wt.Hap) Biocomposites as a Bone Biodegradable Implant Material Sitompul, Henni; Dahlan, Kiagus; Noviana, Deni; Silalahi, Marzuki; Sukaryo, Sulistioso Giat; Gunanto, Yohanes Edi
Jurnal Fisika dan Aplikasinya Vol 15, No 1 (2019)
Publisher : Lembaga Penelitian dan Pengabdian Masyarakat, LPPM-ITS

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (904.498 KB) | DOI: 10.12962/j24604682.v15i1.3797

Abstract

In recent years, development of magnesium (Mg) as biodegradable implant very rapidly in orthopedic applications. This is due to its young’s modulus close to young modulus of natural bone. However, Mg implants demonstrate higher biological activity which could cause high degradation rate in human bio-environment. Consequently, needed to develop Mg-based alloys with superior corrosion performance. In the present study, it has been attempted to develop biocomposite of Magnesium Zinc-5% Hydroxyapatite (MgZn-5%HAp) as biodegradable bone implant. The biocomposites were prepared by adding 5wt.% powders to MgZn powder and then were sintered at temperature 350 oC in vacuum furnace for holding an hour. The characterization of MgZn-5wt%HAp biocomposite was examined by Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM/EDS) and X-ray diffraction (XRD) while corrosion tested by potensiostat. The SEM / EDS and XRD results indicated that some of the Zn atoms have dissolved in Mg to form a MgZn solid solution. The SEM results also showed that the MgZn-5%HAp biocomposite has a microstructure with a matrix Mg and HAp at the grain boundary. The presence of HAp in the sample resulted in a smaller crystallite size and corrosion rate compared to  the one with MgZn alloy.
ULTRASONIC TREATMENT EFFECT ON THE CONSOLIDATION OF Fe-Cr PARTICLE MIXTURES AFTER COMPACTION AND SINTERING PROCESS Silalahi, Marzuki; Untoro, Pudji; Suharno, Bambang; Harjanto, Sri
Metalurgi Vol 29, No 2 (2014): Metalurgi Vol.29 No.2 Agustus 2014
Publisher : Pusat Penelitian Metalurgi dan Material - LIPI

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (449.765 KB) | DOI: 10.14203/metalurgi.v29i2.289

Abstract

ULTRASONIC TREATMENT EFFECT ON THE CONSOLIDATION OF Fe-Cr PARTICLEMIXTURES AFTER COMPACTION AND SINTERING PROCESS. Fe-Cr microalloys which obtained byultrasonic method are the initial cores for the consolidation process. Therefore its facilitate the formation of thehomogeneous bulk of Fe-Cr alloy with a stable phase. In this research, the synthesis of bulk of Fe-Cr alloy fromthe particles mixture of (Fe+Cr) as the ultrasonic treatment results has been carried out. The particlesconsolidation has been carried out through a process of compaction without adding any lubricants and followedby sintering process in the quartz glass capsules by using induction furnace at 1300 °C. Consolidation of mixtureof Fe-Cr particles that have not undergone previous ultrasonic treatment is also made for a comparison. Theinvestigation by using the SEM (scanning electron microscope)- and density measurements method werepreformed on the Fe-Cr green powders compaction. The bulk of Fe-Cr alloys that are produced trough sinteringprocess was observed using SEM-EDS (energy dispersive spectroscopy), XRD (x-ray diffraction), and densitymeasurements method. The bulk of Fe-Cr alloy prepared with ultrasonically treated Fe-Cr microalloy powders,is more homogeneous in composition and has a better phase stability in comparison to Fe-Cr powders preparedwithout the ultrasonic treatment. Production of bulk Fe-Cr alloy in quartz glass capsule during the sinteringprocess has produced Fe-Cr alloy without oxides.
PENGARUH JENIS PADUAN MIKRO FE-CR HASIL METODE ULTRASONIK PADA PEMBENTUKAN BONGKAH PADUAN FE-CR MELALUI SINTERING DUA TAHAP Silalahi, Marzuki; Untoro, Pudji; Suharno, Bambang; Harjanto, Sri
Jurnal Sains Materi Indonesia Vol 15, No 3: APRIL 2014
Publisher : Center for Science & Technology of Advanced Materials - National Nuclear Energy Agency

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1108.741 KB) | DOI: 10.17146/jsmi.2014.15.3.4353

Abstract

PENGARUH JENIS PADUAN MIKRO Fe-Cr HASIL METODE ULTRASONIK PADA PEMBENTUKAN BONGKAH PADUAN Fe-Cr MELALUI SINTERING DUA TAHAP. Fe-Cr adalah paduan yang memiliki ketahanan pada suhu tinggi dan potensial digunakan sebagai interkonek pada sel bakar Solid Oxide Fuel Cell (SOFC). Pada penelitian ini telah dilakukan sintesis bongkah paduan Fe-Cr dengan menggunakan serbuk paduan mikro Fe-Cr hasil sintesis dengan metode ultrasonik. Metode ultrasonik dimanfaatkan untuk sintesis paduan mikro Fe-Cr melalui penggunaan gelombang suara ultrasonik. Langkah yang dilakukan adalah konsolidasi partikel paduan mikro Fe-Cr melalui kompaksi tanpa lubrikan, kemudian dalam kapsul kaca kuarsa dilakukan proses sintering sampai 1000 oC selama 1 jam, lalu dilanjutkan sintering hingga 1300 oC selama 2 jam, lalu didinginkan dalam tungku. Karakterisasi struktur mikro dilakukan dengan Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Spectroscopy (SEM-EDS), X-Ray Diffraction (XRD) disertai analisis dengan metode Rietveld dan pengukuran densitas sesungguhnya. Partikel paduan mikro Fe-Cr seutuhnya lebih stabil dan konsisten dalam pembentukan fasa bongkah paduan Fe-Cr melalui sintering bertahap. Diperoleh bongkah paduan Fe-Cr homogen tanpa oksida.
THE SYNTHESIS OF PBZR0.52TI0.48O3 AND PBZR0.58TI0.42O3 CERAMIC POWDER BY USE MOLTEN SALT METHOD AND ITS INTERMEDIATE PRODUCT ANALYSIS Ahda, Syahfandi; Mardiyanto, Mardiyanto; Taufiq, Agus; Silalahi, Marzuki
Majalah Ilmiah Pengkajian Industri Vol 13, No 3 (2019): Majalah Ilmiah Pengkajian Industri
Publisher : BPPT

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (360.246 KB) | DOI: 10.29122/mipi.v13i3.3617

Abstract

Lead zirconat titanate, Pb(Zr1-x,Tix)O3 is a material with high piezoelectric properties and many studies have been carried out in development, in order to improve the materials quality in various applications. Therefore,one of them is the development of synthesis with the molten salt method in this study. Choice of the molten salt method is simply and and not expensive. The salt ratio of NaCl / KCl at 1: 1 in moles as a solvent medium was carried out in synthesizing Pb(Zr1-x,Tix)O3. Likewise, the salt ratio with reactant/basic material was 1: 1 in weight percentages. An intermediate product is obtained if the dynamics of chemical reactions in the diffusion process occur indirectly or in stages. To identify intermediate products in this synthesis process, the sintering temperature has been varied to 575, 675 and 775 oC for samples A, B and C, respectively. The results of these syntheses have been identified and characterized using x-ray diffraction (XRD) methods. The Highscore program using the Rietveld method to identify the intermediate product content and each crystal structure has been applied in the rifenement process on the XRD intensity profile with a statistical error of less than 6%. Intermediate products have been obtained as follows, PbTiO3, PbZrO3 and Zr0.4Ti0.6O3. Whereas sample C has obtained two phases namely PbZr0.52Ti0.48O3 and PbZr0.58Ti0.42O3 with tetragonal (P4mm) and rhombohedral crystal structures (R3c).