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This study provides a prediction of multi-component alloy AlCrFeNiM by calculating the parameters VEC, ΔΧ, Ω, and δ. In the experiment, the AlCrFeNiM (M=Mo and Zr) were produced by powder metallurgy with sintering at different temperatures varied from 800, 900, and 1000 °C. Phase identification and structural analysis from their diffraction patterns were investigated. The diffraction pattern shows that a complex phase component occurs in the alloys. The B2 phase is generally found for both alloys for all sintering temperatures. In AlCrFeNiMo alloy sintered at a temperature of 800 °C, the Al3Ni2 phase is identified as dominant. In AlCrFeNiZr alloy sintered at a temperature of 1000 °C, the B2 phase content is comparable to the fcc phase. The theoretical density of alloys was also obtained. The results indicate that the alloys AlCrFeNiMo sintered at 800 °C, and AlCrFeNiZr sintered at 900 °C have the lowest density in the series. [ABSTRACT FROM AUTHOR]

Investigation of high-temperature X-ray diffraction is a tool for the characterization of structural parameters of materials. Material characterization at high-temperature is needed for many research and industrial applications. In order to ensure the data quality, thermal exposure inside the chamber must be known well. Corundum is one of the materials that does not undergo a phase change but shows the phenomenon of thermal expansion at low temperatures, so it is very good for testing heat exposure inside the chamber. In this study, we investigated the changes in the corundum structure during heating to find out how the corundum receives heat in the chamber. Particle size characterization was carried out on the corundum to ensure a good X-ray diffraction pattern was obtained. X-ray diffraction measurements using a high-temperature sample stage were carried out at 373, 473, and 573 K. The results showed that the particle size of corundum was in micron size with D50 value at 101.2 µm. The lattice parameters increased during heating. The ratio c/a increases slightly during the process of heating, around 2.73. Changes in lattice parameters showed that thermal expansion occurs. The thermal expansion derived from the X-ray diffraction pattern was lower compared to thermal expansion from the calculation. The difference in this thermal expansion value can indicate that the heat received by the corundum inside the chamber has not reached the intended temperature. [ABSTRACT FROM AUTHOR]

Aluminum alloy of AG3NE were synthetized by casting method. The AG3NE application meant to be as nuclear fuel cladding candidate for nuclear research reactor that currently using the AlMg2. The AG3NE would apply for high density uranium nuclear fuel. Analysis for its structural properties were done by implementing the Williamson-Hall and size-strain plotting method, and the Rietveld analysis on the X-ray Diffraction profile data. The Williamson-Hall and size-strain plot were used to analysis the contribution of crystallite sizes and lattice strain occurs in Al alloys. The Rietveld analysis was used to showed the structural changes in Al phase. The analysis results showed that the AG3NE had lower crystallite size, microstrain and lattice parameter value compared to AlMg2. The crystallite size value for AG3NE and AlMg2 were 1.2130 nm and 3.7474 nm, respectively. The microstrain value for AG3NE and AlMg2 were 0.0076 and 0.0352, respectively. The lattice parameter value AG3NE and AlMg2 were 4.0558 Å and 4.0604 Å, respectively. [ABSTRACT FROM AUTHOR]

Hydroxyapatite is a well-known biocompatible material which is widely used as bone graft and bone cement. In this study, hydroxyapatite was extracted from red snapper bone waste using mechanochemical methods. This study aims to optimize the milling time of the hydroxyapatite extraction process from red snapper bone waste. The extraction process begins by grinding the bone into a fine powder and then soaking it in chloroform while sonicating and drying. Then NaOH was added to the powder in a cylindrical jar and after that the mixture was ground with various grinding times. The milling products were then characterized by thermal gravimetric analysis (TGA), Fourier transform infra-red (FTIR) and X-ray diffraction (XRD). The results showed that there was a decrease in mass loss at each additional milling time with the largest loss at 30 minutes of milling and the smallest loss at 480 minutes of milling. TGA analysis also revealed a decrease in mass with each increase in milling time when the sample was heated from 30°C to 25°C. FTIR analysis showed that the red snapper bone powder contained CH and CN organic groups from samples with milling times of 30 and 60 minutes, while the typical hydroxyapatite functional groups, namely OH−, PO43-, and CO32-, were present in all samples. The presence of the CO32- group was also confirmed by XRD where type B hydroxyapatite appeared as the secondary phase. XRD analysis also informed that the crystal size of all samples of Red Snapper fish bones was in the range of 8.61 – 21.51 nm with a degree of crystallinity of 28.53 to 48.43% and the Ca/P molar ratio was from 1.69 – 1.93. Therefore, based on material decomposition, crystal structure, crystal size and Ca/P molar ratio, it can be concluded that the optimum milling time in this process is about 120 minutes. [ABSTRACT FROM AUTHOR]

Hydroxyapatite (HA), Ca10(PO4)6(OH)2, is one of the most widely used synthetic bone graft materials in dental and orthopedic applications. The crystallite size of HA influence bioactive properties during bone resorption. In this study, determination of crystallite size value in synthetic hydroyapatite had been conducted from x-ray diffraction pattern by using Scherrer, Monshi-Scherrer, Williamson-Hall, Halder-Wagner, and Size Strain Plot Method. During the manufacturing process of synthetic hydroxyapatite, the CaOH and H3PO4 solutions were added with a non-titration and a titration precipitation technique. The synthetic hydroxyapatite was then heat-treated at 1000°C. The crystallite size of synthetic hydroxyapatite produced with a non-titration and a titration technique was 83.14 and 55.69 nm in the Scherrer method where considering the available peaks fit to the Straight Line Passing the Origin of Scherrer. Those values are close to the crystallite size values of 81.06 and 43.87 nm for the non titration and titration hydroxyapatite provided by Monshi Scherrer method, respectively. The values 66.59 and 37.02 nm were given by the Williamson-Hall plot method for the synthetic hydroxyapatite produced with a non-titration and a titration technique, respectively. The Halder-Wagner method gave 55.96 and 39.90 nm of the synthetic hydroxyapatite produced with a non-titration and a titration technique, respectively. The crystallite size value of 62.51 nm for non-titration hydroxyapatite and 38.26 nm for titration hydroxyapatite given by the size strain plot method. While, the crystallite size of titration HA which is calculated with Williamson-Hall, Halder-Wagner, and size strain plot methods, provide relatively close values. The Halder-Wagner and Size Strain Plot Method gave a strong linear correlation to the other methods. From all of the calculation methods, the crystallite size of hydroxyapatite produced by non-titration technique has a higher value compared to the titration technique. [ABSTRACT FROM AUTHOR]

Uranium ore concentrate plays an essential role in the fabrication of uranium dioxide. Uranium ore concentrate as ammonium diuranate (ADU) is an intermediate nuclear material, making it one of the materials of concern in nuclear forensics. In industrial processes, ADU was dried at the temperature range of 120 – 400 °C and the calcination process in the temperature range of 400 – 850 °C, which allows for changes in morphology and structure. The final product is very dependent on the starting material. The ADU powder from the pilot conversion plant (PCP) – BRIN needed to be characterized for its fingerprint. Heat treatment was varied at 250 °C, 300 °C, and 400 °C with an air atmosphere. Characterization included uranium content, morphological observations using a Scanning Electron Microscope (SEM), and revealing the phase composition using X-Ray diffraction (XRD). The results showed that the uranium content increased with increasing temperature, the highest at a temperature of 400 °C, where the uranium content is 79.66 ± 0.51%. Visually, the pore size of the powder is getting smaller, and the amount decreases with increasing temperature. In ADU powder, before heat treatment consists of two phases, and after the heat treatment forms three phases. The results of this characterization can be devoted to a nuclear forensics database of nuclear and radioactive materials. [ABSTRACT FROM AUTHOR]

Zr-4 alloy in the nuclear industry is used as a cladding material for PWR. In order to prepare for the fabrication and prototype of PWR fuel, PRTBBNLR has carried out irradiation tests on Zr-4 cladding material at the G.A. Siwabessy power ramp test facility. The cladding material is Zr-4 alloy in the form of a short pin. Irradiation is carried out at a power of 15 MW, the average thermal neutron flux is 1.15 x 1013 with the highest thermal neutron flux distribution 4.65 x 1013 and the lowest thermal neutron flux is 3.14 x 1010, the secondary coolant outlet temperature is 42 °C, and the pressure is in the range of 16.5-17.5 MPa for 350 hours. To determine the mechanical performance of the cladding material, it is necessary to do a post-irradiation test in a radiometallurgy installation. Post-irradiation tests that have been carried out are tensile tests and microhardness tests. Tensile strength and hardness of the cladding material is one of the mechanical properties that can change due to irradiation in the reactor. Tensile strength was observed in the transverse direction so that the sample used was a ring without a notch with a width of 3 mm, a thickness of 0.8 mm and an inner diameter of 0.9 mm. The preparation was carried out in hot cell 104 using low speed cutting. The tensile strength was tested using a Shimadzu engine with a capacity of 10 kN at R.206. The hardness of the material was tested using microhardness with a load of 500 gF in hot cell 112. The results showed that the tensile strength and hardness of the post-irradiated sample were lower than the pre-irradiated tensile strength. However, the ductility of Zr-4 material post-irradiation and pre-irradiation did not change significantly. [ABSTRACT FROM AUTHOR]

Indonesia has two TRIGA research reactors operating in Bandung and Yogyakarta. TRIGA reactor uses UZrH1.6 fuel with SS304 fuel cladding. During reactor operation, the fuel cladding potentially has performance decreasing, especially on mechanical integrity. The aim of this study was to determine the effect of the cyclic oxidation on the tensile strength and hardness value of SS304 as fuel cladding in research reactor. The SS304 specimen was oxidized in cyclic oxidation in a furnace for 35 hours each cycle at temperatures of 300, 400, 500 and 600°C, respectively. Tensile test results show remaining strength at all of test temperature with 446 - 512 N/mm2 UTS range. The hardness test results show increasing trend of hardness value with increasing temperature. In general, cyclic oxidation treatment at these temperatures does not cause mechanical integrity degradation. [ABSTRACT FROM AUTHOR]

The by-product formed by radioactive mineral processing industry may contain radionuclides which could cause a radiological impact on workers, the surrounding community, and the environment. The use of bentonite as an adsorbent for wastewater treatment is widespread and has been proven to treat radionuclides contaminants such as Cs, Sr, Eu, Th, U, Co, and Pu. This study was conducted to study the characteristics of raw bentonite and its modification using acid and thermal activation to determine the potential of the bentonite to adsorbed thorium and uranium radionuclides. The bentonite used in this study was collected from Pacitan, East Java, which was activated with the variation acid concentration and heating temperature. The modified bentonite was characterized using Fourier Transform Infrared (FT-IR) to analyze the functional group, X-ray Diffraction (XRD) to determine the crystallinity of the material, X-ray fluorescence (XRF) to investigate the chemical composition, Scanning Electron Microscope (SEM) to analyze the morphology, and Brunauer-Emmett-Teller (BET) to measure the surface area and pore volume of the modified bentonite. The characterization obtained in this study proves that the presence of Ca-montmorillonite with the optimum condition in acid-activated bentonite can increase its capacity and be a promising adsorbent for wastewater treatment, especially for further study in radionuclides adsorption. [ABSTRACT FROM AUTHOR]

The pure iron sample was treated using gas nitriding at 1000 °C for 1 hour. The morphology and phase analysis of the nitride layer was characterized by scanning electron microscope and X-ray diffraction. The thickness of the nitride layer and average grain size were derived from the scanning electron microscope micrograph. The crystallite size was determined by X-ray diffraction using the Williamson-Hall method. The micrograph from the scanning electron microscope showed a nitride layer, a diffusion zone, and a narrow gap between them. The thickness of the nitride layer was 8.1 ± 0.5 µm with a visible gap in the diffusion zone of 1.5 ± 0.5 µm. The grain size in the diffusion zone increased, and some interstitial to the iron lattice and/or precipitate at the grain boundary were observed. The phase analysis of the nitride layer showed a single phase ε-Fe2N with a crystallite size number of 549 Å. [ABSTRACT FROM AUTHOR]

The Center for Nuclear Fuel Technology (PTBBN) in BATAN needs to strengthen its strategy in light of the enhanced tasks of BATAN as the Implementing Organization under the National Research Agency (BRIN) to carry out research, development, assessment and application as well as inventions and innovations in an integrated manner. Following the experience and lessons learned in the past 3 decades and change of workforce generation, a strategic assessment is performed to evaluate and strengthen the fuel program for light water reactor (LWR) to support the development of a Prototype Commercial Scale Nuclear Power Plant, as outlined in the National Research Priority 2020-2024. Collaboration with the national and international stakeholders is essential to further enhance the knowledge and know-how of fuel technology and to improve the quality of the fuel program in areas with gaps and proprietary nature (e.g. fuel specifications, qualification requirements, benchmarking). The study reviews the current status and challenges of the fuel program in Indonesia and revisits the business process of PTBBN. Mapping of existing and planned capabilities as well as potential collaboration with relevant stakeholders is performed. Consultation is being conducted with the national nuclear experts. Fuel strategies, experience and standard practice in other countries are examined. The results show that mastery of nuclear fuel technology requires strong government support in terms of manpower, materials and funding, and collaboration with international partners. Preliminary considerations for a strategy framework for the development of LWR fuel prototype are presented. Considerations for domestic fuel fabrication should take into account the economics and strategic value, and further studies must be performed on feasibility, risks, cost and benefit. [ABSTRACT FROM AUTHOR]

The development of magnetocaloric effect (MCE) material is done in order to reduce the damage of the ozone layer caused by the chlorofluorocarbons (CFCs) emitted into the air. The research dealing with synthesis of magnetocaloric materials based of Ni-Al Heusler Alloy structure and by varying substitution some atoms of Ni with Fe and A1 with Mn on Ni-Al Heusler Alloy structure to become Ni44Fe6Mn32Al18. Vacuum Arc Melting (VAM) equipment is used to form the alloys on vacuum condition and by flowing argon gas atmosphere and then followed by annealing process for 72 hours. X-Ray Diffraction (XRD) reveals that crystallite structure of material is observed. We define that Ni44Fe6 as X2, Mn25 as Y, and Al18Mn7 as Z. Based on the XRD result, we observed that the general formula X2YZ is not changed. The PERMAGRAF measurement revealed that there exists of magnetic hysterysis. The hysterysis show that the magnetic structures of the system undego evolution from diamagnetic to soft ferromagnetic material which all of the compound have the same crystallite structure. This evolution indicated that the change in the composition has led to changes the magnetic composition. Mn is the major element that gives strong magnetic properties to the sample. When Mn partially replaced position of Al, the sample became dominant to be influenced to improve their magnetic properties. In addition, substitution a part of Ni by Fe in the composition reveals a pinning of the domain walls in the sample. [ABSTRACT FROM AUTHOR]