scholarly journals Magnetic Behavior of Natural Fe2O3 from Lhoong Iron Ore Mining Area, Aceh Province, Indonesia

2013 ◽  
Vol 2013 ◽  
pp. 1-4 ◽  
Author(s):  
Adi Rahwanto ◽  
Mustanir Yahya ◽  
Zulkarnain Jalil
Keyword(s):  
Iron Ore ◽  
Milling Time ◽  
Magnetic Behavior ◽  
Mining Area ◽  
Milling Process ◽  
Chemical Compositions ◽  
Mineral Component ◽  
Aceh Province ◽  
Milling Method ◽  
Fine Crystalline Structure

The mineral composition and magnetic behavior of nano-Fe2O3 of iron ore from Lhoong mining area, Aceh province, were studied. The iron ore was prepared by mechanical milling method. The mineral and chemical compositions of samples were investigated by XRD and XRF analysis tests. The XRF test showed that the Lhoong iron ore contains Fe2O3 (93.88%) in association with other isomorphous impurities, such as SiO2, MnO, and Al2O3, in varying proportions. Compared to XRD results, it was consistent with XRF; the phase compositions of iron ore were mainly hematite (Fe2O3). The XRD revealed that hematite was the major mineral component in the Lhoong iron ores. SEM observation showed fine crystalline structure of Lhoong iron ore after the milling process. The main mineral morphology was microcrystalline in agglomerate forms. The magnetic properties of the samples after milling showed the increasing in the remanent (Br) and coercivity (Hc). This increasing can be explained that nano-Fe2O3 phase after milling for 20 hours plays an important role in the magnetic behavior of Lhoong iron ore. It is understood that the longer milling time is sufficient to complete the transformation of hematite (Fe2O3) to magnetite (Fe3O4).

scholarly journals Synthesis of Nanohydroxyapatite from Cuttlefish Bone (Sepia sp.) Using Milling Method

2019 ◽  
Vol 2019 ◽  
pp. 1-6
Author(s):  
Aminatun ◽  
Adri Supardi ◽  
Zulifah Izzatin Nisa ◽  
Dyah Hikmawati ◽  
Siswanto
Keyword(s):  
Compressive Strength ◽  
Cell Viability ◽  
Bone Repair ◽  
Milling Time ◽  
High Energy ◽  
Milling Process ◽  
Viability Test ◽  
Strength Tests ◽  
Milling Method

The synthesis of nanohydroxyapatite from cuttlefish bone (Sepia sp.) has been done by using High Energy Milling (HEM) and its characterization in vitro as bone repair. This study aimed to determine the effect of the milling process on microscopic properties and mechanical properties of nano-HA through XRD, TEM, and compressive strength tests. The hydroxyapatite (HA) used in this study consisted of 1M CaCO3 from aragonite which was extracted from cuttlefish lamella bone (Sepia sp.) and 0.6 M NH4H2PO4, which was hydrothermally processed at 200°C for 12 h and then sintered at 900°C for 1h. Parameter milling includes the variation of milling time, i.e., 3 h, 6 h, and 9 h at rotational speed of 350 rpm. An increase in milling time causes a decrease in HA particle size. This is shown from the results of TEM at the milling time of 9 h with the smallest size up to 65 nm. The result of cell viability test showed that all samples are not toxic with cell viability value of >80%. The milling time of 9 h was an optimum condition with a compressive strength of 4.35952 MPa that can be applied to cancellous bone.

scholarly journals PREPARASI PARTIKEL MAGNETIK DARI PASIR BESI PANTAI BATANG KAPAS SUMATERA BARAT MENGGUNAKAN METODE BALL MILLING

2018 ◽  
Vol 15 (2) ◽  
pp. 120
Author(s):  
Tahayati Ichsan ◽  
Salomo Salomo ◽  
Erwin Erwin ◽  
Usman Malik
Keyword(s):  
Magnetic Susceptibility ◽  
Ball Milling ◽  
Magnetic Induction ◽  
Magnetic Particles ◽  
Magnetic Particle ◽  
Milling Time ◽  
Milling Process ◽  
Sand Beach ◽  
Calculation Results ◽  
Milling Method

Preparation of micro magnetic particle and its magnetic propertis from iron sand beach of Batang Kapas west Sumatera using Ball Milling method has been done. Prior to the Ball Milling process, the samples were processed by iron sand separator (ISS) in order to separate between magnetic particles and non magnetic one. Next, the concentrates from ISS were crushed by Ball Milling method  as a function of time namely 20, 40, and 60 hours. For separation between magnetic particles and non magnetic one, then NdFeB magnet was utilized. The results showed that the magnetic degree of the sample is about 0,5%. Measurements of magnetic induction solenoids were carried out using a Magnetic Probe Pasco PS -2162 as a function of current (2, 4, 6, 8 and 10) A and a  functions of distance (1, 2, 3, 4, and 5) mm. Then the total magnetic induction of the solenoid (solenoid with sample core and concentrate) was measured as a function of an electric current for a fixed distance of 1 mm. The calculation results showed that magnetic susceptibility and mass susceptibility increase with Ball Milling time from (3376,400-7765,130). This value is within the interval of 46-80000 which is the interval of Ilmenite mineral (FeTiO3; Antiferromagnetik). The increase in magnetic susceptibility and mass susceptibility of samples processed by Ball Milling is thought to be due to the increasing number of magnetic particles in the sample.

Influence of Ball Milling Process on the Pinned Effect of Al2O3/Al Cermet Composite Powder

2018 ◽  
Vol 777 ◽  
pp. 80-84
Author(s):  
Jie Guang Song ◽  
Yue Liu ◽  
Long He ◽  
Jin Shi Li ◽  
Wang Chen ◽  
...  
Keyword(s):  
Ball Milling ◽  
High Performance ◽  
Milling Time ◽  
Raw Materials ◽  
Milling Process ◽  
Composite Powders ◽  
Rotating Speed ◽  
Milling Method ◽  
Cermet Materials ◽  
Ball Milling Time

The Al2O3/Al cermet composite powders were prepared via the ball milling method,which provide raw materials for preparing high performance cermet materials. The results show that the number of Al2O3 particles on the surface of Al particles increases first and then decreases with increasing the ball milling time and milling rotating speed. The number of Al2O3 particles on the surface of Al particles increases with increasing ball to powder mass ratio. The analysis of the ratio of performance to price shows that the better parameters for preparing the pinned Al2O3/Al cermet composite powders are as follows, the ball milling time 24h,the ball milling rotating speed 100 r/min and the ratio of ball to powder 1:2.

scholarly journals Towards Efficient Milling of Multi-Cavity Aeronautical Structural Parts Considering ACO-Based Optimal Tool Feed Position and Path

Micromachines ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 88
Author(s):  
Yupeng Xin ◽  
Yuanheng Li ◽  
Wenhui Li ◽  
Gangfeng Wang
Keyword(s):  
High Speed ◽  
Tool Path ◽  
Milling Process ◽  
Ant Colony ◽  
Machining Accuracy ◽  
Ant Colony Optimization Algorithm ◽  
Peripheral Milling ◽  
Structural Part ◽  
Milling Method ◽  
Structural Parts

Cavities are typical features in aeronautical structural parts and molds. For high-speed milling of multi-cavity parts, a reasonable processing sequence planning can significantly affect the machining accuracy and efficiency. This paper proposes an improved continuous peripheral milling method for multi-cavity based on ant colony optimization algorithm (ACO). Firstly, by analyzing the mathematical model of cavity corner milling process, the geometric center of the corner is selected as the initial tool feed position. Subsequently, the tool path is globally optimized through ant colony dissemination and pheromone perception for path solution of multi-cavity milling. With the advantages of ant colony parallel search and pheromone positive feedback, the searching efficiency of the global shortest processing path is effectively improved. Finally, the milling programming of an aeronautical structural part is taken as a sample to verify the effectiveness of the proposed methodology. Compared with zigzag milling and genetic algorithm (GA)-based peripheral milling modes in the computer aided manufacturing (CAM) software, the results show that the ACO-based methodology can shorten the milling time of a sample part by more than 13%.

Development of Biodegradable Mg-Ti Alloy Synthesized Using Mechanical Alloying

2016 ◽  
Vol 1133 ◽  
pp. 75-79 ◽  
Author(s):  
Emee Marina Salleh ◽  
Sivakumar Ramakrishnan ◽  
Zuhailawati Hussain
Keyword(s):  
Mechanical Alloying ◽  
Milling Time ◽  
Milled Powder ◽  
Milling Process ◽  
Planetary Mill ◽  
Ti Alloy ◽  
X Ray Diffraction ◽  
Argon Flow ◽  
Diffraction Patterns ◽  
Ti Powder

The aim of this work was to study the effect of milling time on binary magnesium-titanium (Mg-Ti) alloy synthesized by mechanical alloying. A powder mixture of Mg and Ti with the composition of Mg-15wt%Ti was milled in a planetary mill under argon atmosphere using a stainless steel container and balls. Milling process was carried out at 400 rpm for various milling time of 2, 5, 10, 15 and 30 hours. 3% n-heptane solution was added prior to milling process to avoid excessive cold welding of the powder. Then, as-milled powder was compacted under 400 MPa and sintered in a tube furnace at 500 °C in argon flow. The refinement analysis of the x-ray diffraction patterns shows the presence of Mg-Ti solid solution when Mg-Ti powder was mechanically milled for 15 hours and further. Enhancements of Mg-Ti phase formation with a reduction in Mg crystallite size were observed with the increase in milling time. A prolonged milling time has increased the density and hardness of the sintered Mg-Ti alloy.

255 Evaluation of Different Corn Milling Methods for High-moisture and Dry Corn on Nutrient Digestion

2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 124-125
Author(s):  
Caitlin A Coulson ◽  
Nicole Woita ◽  
Tyler Spore ◽  
Hannah Wilson ◽  
Kylie Butterfield ◽  
...  
Keyword(s):  
Dry Matter ◽  
Milling Process ◽  
Nutrient Digestibility ◽  
Hammer Mill ◽  
High Moisture ◽  
Roller Mill ◽  
Nutrient Digestion ◽  
Milling Method ◽  
Feeding Diets ◽  
Effect Of Feeding

Abstract A 2 × 2 factorial digestion study using seven ruminally cannulated steers evaluated the effect of feeding diets containing 70% (dry matter-basis) high-moisture (HMC) or dry corn (DC), processed with either a hammer mill or Automatic Ag Roller Mill (Pender, NE), on nutrient digestion. Feeding HMC decreased the amount of excreted dry matter (DM) and organic matter (OM; P ≤ 0.01) regardless of mill type, but there was a tendency (P ≤ 0.13) for an interaction between corn type and mill type for DM and OM digestibility. There was no difference between either milling treatments fed as HMC (P ≥ 0.69), but the hammer mill DC diet was more digestible than the roller mill DC (P = 0.05). There was no effect on NDF digestibility, but there was a tendency for an interaction between grain type and processing method for ADF digestibility, with the roller mill DC diet having the lowest (P = 0.02) ADF digestibility and no differences (P ≥ 0.15) among the other treatments. As expected, HMC based diets had greater (P < 0.01) starch digestibility compared to DC, but milling method had no effect (P = 0.56). High moisture corn diets had greater (P = 0.01) DE intake (Mcal/kg), and hammer mill DC tended to be greater (P = 0.07) than roller mill DC. There tended (P = 0.07) to be an interaction for minimum pH, with roller mill HMC and hammer mill DC having the lowest average pH, but not different from hammer mill HMC (P ≥ 0.32). There were no differences (P = 0.56) in average pH, but HMC diets had greater variance (P = 0.04) and greater area under pH 5.6 (P = 0.05) compared to DC based diets. Feeding cattle HMC compared to DC increases nutrient digestibility but milling process had little impact.

scholarly journals The Mineral Chemistry of Chlorites and Its Relationship with Uranium Mineralization from Huangsha Uranium Mining Area in the Middle Nanling Range, SE China

Minerals ◽  
2019 ◽  
Vol 9 (3) ◽  
pp. 199 ◽  
Author(s):  
Dehai Wu ◽  
Jiayong Pan ◽  
Fei Xia ◽  
Guangwen Huang ◽  
Jing Lai
Keyword(s):  
Mining Area ◽  
Uranium Mining ◽  
Uranium Mineralization ◽  
Formation Mechanisms ◽  
Chemical Compositions ◽  
Type I ◽  
Low Oxygen ◽  
Nanling Range ◽  
The Relationship ◽  
Uranium Mining Area

The Huangsha uranium mining area is located in the Qingzhangshan uranium-bearing complex granite of the Middle Nanling Range, Southeast China. This uranium mining area contains three uranium deposits (Liangsanzhai, Egongtang, and Shangjiao) and multiple uranium occurrences, showing favorable mineralization conditions and prospecting potential for uranium mineral resources. Chloritization is one of the most important alteration types and prospecting indicators in this mining area. This study aims to unravel the formation environment of chlorites and the relationship between chloritization and uranium mineralization, based on detailed field work and petrographic studies of the wallrock and ore samples from the Huangsha uranium mining area. An electron probe microanalyzer (EPMA) was used in this study to analyze the paragenetic association, morphology, and chemical compositions of chlorite, to classify chemical types and to calculate formation temperatures and n(Al)/n(Al + Mg + Fe) values of chlorite. The formation mechanism and the relationship with uranium mineralization of the uranium mining area are presented. Some conclusions from this study are: (1) There are five types of chlorites, including the chlorite formed by the alteration of biotite (type-I), by the metasomatism of feldspar with Fe–Mg hydrothermal fluids (type-II), chlorite vein/veinlet filling in fissures (type-III), chlorite closely associated with uranium minerals (type-IV), and chlorite transformed from clay minerals by adsorbing Mg- and Fe-components (type-V). (2) The chlorite in the Huangsha uranium mining area belongs to iron-rich chlorite and is mainly composed of chamosite, partly clinochlore, which are the products of multiple stages of hydrothermal action. The original rocks are derived from argillite, and their formation temperatures vary from 195.7 °C to 283.0 °C, with an average of 233.2 °C, suggesting they formed under a medium to low temperature conditions. (3) The chlorites were formed under reducing conditions with low oxygen fugacity and relatively high sulfur fugacity through two formation mechanisms: dissolution–precipitation and dissolution–migration–precipitation; (4) The chloritization provided the required environment for uranium mineralization, and promoted the activation, migration, and deposition of uranium.

scholarly journals The Structural Evolution of Al86Ni9La5 Glassy Ribbons during Milling at Room and Cryogenic Temperatures

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1956
Author(s):  
Zhicheng Yan ◽  
Yan Liu ◽  
Shaopeng Pan ◽  
Yihua Hu ◽  
Jing Pang ◽  
...  
Keyword(s):  
Milling Time ◽  
Shear Bands ◽  
Structural Evolution ◽  
High Energy ◽  
Milling Process ◽  
Cryogenic Temperatures ◽  
Dynamic Simulations ◽  
Tricapped Trigonal Prism ◽  
Medium Range ◽  
Energy Ball

Melt-spun metallic Al86Ni9La5 glassy ribbons solidified at different circumferential speeds (Sc) were subjected to high-energy ball milling at room and cryogenic temperatures. Crystallization induced by milling was found in the Al86Ni9La5 solidified at lower circumferential speed (Sc = 14.7 m/s), while the Al86Ni9La5 with Sc = 36.6 m/s kept amorphous. Besides, a trend of structural rejuvenation during milling process was observed, as the onset temperatures (Tx1, Tx2) and the crystallization enthalpies (ΔH1, ΔH2) first decreased and then increased along with the milling time. We explored the structural origin of crystallization by ab initio molecular dynamic simulations and found that the tricapped trigonal prism (TTP) Ni-centered clusters with a higher frequency in samples solidified at a lower cooling rate, which tend to link into medium-range orders (MROs), may promote crystallization by initiating the shear bands during milling. Based on the deformation mechanism and crush of metallic glasses, we presented a qualitative model to explain the structural rejuvenation during milling.

scholarly journals Electrical Conductivity Behavior of La0.5Ca0.5Mn0.5Fe0.5O3 Synthetized by the Solid State Reaction

2018 ◽  
Vol 12 (12) ◽  
pp. 174
Author(s):  
H. A. Martínez-Rodríguez ◽  
J. F. Jurado ◽  
E. Restrepo-Parra
Keyword(s):  
Solid State ◽  
Thermal Treatment ◽  
Solid State Reaction ◽  
Milling Time ◽  
Electrochemical Impedance ◽  
Solid State Reaction Method ◽  
Milling Process ◽  
Secondary Phases ◽  
Two Samples ◽  
Semiconductor Behavior

La0.5Ca0.5Mn0.5Fe0.5O3 was synthesized using the solid state reaction method. This method consists of two main processes: a milling process and a subsequent thermal treatment. Two samples at different conditions were produced: one using 2 h of milling time and 900°C (M-I), and the other using 6 h of milling time and 1200°C of thermal treatment (M-II).  X-ray diffraction analysis indicated, in both cases, an orthorhombic crystalline ordering of the space group Pbnm. For the case of M-I, the material exhibited secondary phases, different than the desired phase; on the contrary, in M-II, these secondary phases were not present. The dielectric response determined using electrochemical impedance spectroscopy (EIS) performed in a temperature range between 20°C and 300°C exhibited a thermally activated semiconductor behavior with activation energies of Eg= 0.11±0.05 eV and Eg= 0.47±0.06 eV for M-I and M-II, respectively.

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