Influences of microstructure on macroscopic crystallinity and magnetic properties of Sm-Fe-N fine powder produced by jet-milling

The purpose of this study is to determine the effect of the addition of 2 % SrO on physical, magnetic properties and crystal structure of BaO6Fe2O3. In this study, the coprecipitation method was used with raw materials BaCl2, FeCl3 and SrCl3 and Ba-ferrite composition is used based on the ratio of mole BaO: Fe2O3 = 1: 6, while SrO is used 2% of the weight of Ba-ferrite. The raw materials are dissolved in distilled water, then added a solution (50%) of ammonia to form a perfect precipitate. The precipitate after filtering was dried in an oven at 100°C until dry, then crushed with mortar and partially taken for analysis with DTA / TG. The fine powder was calcined at 800 ° C and held for one hour using an electric furnace. The calcined samples were crushed with mortar and fine powder was added 1% wt.of PVA adhesive and formed with a pressure of 40 MPa to obtaine a pellet sample. The pellet samples were then sintered at 1150°C and hold for 1 hour. Furthermore, the sintered samples were characterized such as measurement of bulk density, magnetic properties with gauss meters and VSM and measurements with XRD. The results of characterization show that the addition of additives 2% of SrO can provide an increase in physical properties and magnetic properties (remanence). But for the crystal structure of XRD analysis there is no change, a single phase is formed, namely BaFe12O19.

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Preparation and Characterization of Sr1−xNdxFe12O19 Derived from Steel-Waste Product via Mechanical Alloying

Materials Science Forum ◽

10.4028/www.scientific.net/msf.846.403 ◽

2016 ◽

Vol 846 ◽

pp. 403-409 ◽

Cited By ~ 5

Author(s):

Noruzaman Daud ◽

Raba’ah Syahidah Azis ◽

Mansor Hashim ◽

Khamirul Amin Matori ◽

Hassan Jumiah ◽

...

Keyword(s):

Magnetic Properties ◽

Iron Oxide ◽

Mechanical Alloying ◽

Doping Concentration ◽

Magnetic Particle ◽

Permanent Magnets ◽

Waste Product ◽

Fine Powder ◽

Raw Material ◽

Temperature Separation

Steel waste product had been used as the main source of raw material in the preparation of permanent magnets ferrites. Steel waste product is an impure material that contains the iron oxide and impurities. The steel waste product is a form of flakes is grinding for several hours to form a fine powder. The iron oxide powder is separated from magnetic and non-magnetic particle using magnetic particle separation. The magnetic particle was again been purified by using the Curie temperature separation technique. The magnetic powder was carried out from the purification and oxidize at 500 °C for 6 hours at 2 °C/ mins to form the hematite, Fe2O3, used as a raw powder to prepare SrFe12O19. Microstructure of Nd-doped strontium ferrites, Sr1-xNdxFe12O19, with x = 0.0, 0.1, 0.2, 0.3, 0.4 and 0.5, were prepared through a mechanical alloying technique. Several characterizations have been done, such as X-ray Diffraction (XRD) and Field emission scanning electron microscopy (FESEM). The magnetic properties of coercivity (Hc) and the energy product BHmax of samples are carried out. The magnetic properties of samples were investigated with an expectation of enhancing the magnetic properties by substitutions of Nd3+ ions on Fe3+ ion basis sites. The saturation magnetization Ms revealed magnetic behavior with respect to Nd3+ doping concentration, showing a decrease. The coercivity Hc increased with increasing Nd3+ doping concentration.

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Influence of jet milling process parameters on particle size, phase formation and magnetic properties of MnBi alloy

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2014.12.202 ◽

2015 ◽

Vol 629 ◽

pp. 80-83 ◽

Cited By ~ 25

Author(s):

N.V. Rama Rao ◽

G.C. Hadjipanayis

Keyword(s):

Particle Size ◽

Magnetic Properties ◽

Phase Formation ◽

Process Parameters ◽

Milling Process ◽

Jet Milling

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Magnetic Properties and Microstructures of Cobalt Substituted Barium Hexaferrites Derived from Steel Waste Product via Mechanical Alloying Technique

Materials Science Forum ◽

10.4028/www.scientific.net/msf.846.388 ◽

2016 ◽

Vol 846 ◽

pp. 388-394 ◽

Cited By ~ 2

Author(s):

Raba’ah Syahidah Azis ◽

Mansor Hashim ◽

Zakaria Azmi ◽

Hassan Jumiah ◽

Noruzaman Daud ◽

...

Keyword(s):

Magnetic Properties ◽

Curie Temperature ◽

Mechanical Alloying ◽

Magnetic Particles ◽

Waste Product ◽

Fine Powder ◽

Raw Material ◽

Steel Mill ◽

Co Doping ◽

Temperature Separation

The mechanical alloying technique was used to prepare barium hexaferrite (BaM) with 3, 5, 10 and 20 wt% cobalt oxide (Co3O4). In this work, steel waste flakes were cold-rolling steel mill for several hours to form a fine powder. The steel waste powder was purified by using magnetic separation to isolate the magnetic and non magnetic particles. The method was continued for Curie temperature separation technique to separate the magnetic ions by varied Curie temperature of the magnetic powder. The purified powder was then oxidize at 500 °C at 6 °C/mins to form hematite, Fe2O3. The steel waste-derived hematite was used as the raw material in preparing BaM ferrites. The BaCO3, Fe2O3 and different percentages of Co3O4 (Co) were mixed and milled for several hours by using mechanical alloying. The powder were pelletised in 11 × 1 mm (diameter × height) and the sintered at 1200 °C for 10 hours. The addition of Co2+/3+ ions to the BaM shows a varying in the magnetic properties of BaM. By increasing the Co doping, the remanence Mr was reduced from 17.6 emu/g to 6.2 emu/g. The coercivity Hc results varying magnitude from 102 Oe to 1079 Oe. The Mr and Hc of undoped BaM is obtain at 14.6 emu/g and 860 Oe, respectively. The grain size of BaM also increases with Co doping. The densities of the compounds are decreasing with increasing Co doping with a maximum value of 4.2 g/cm3.

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HPLC METHOD DEVELOPMENT AND VALIDATION FOR QUANTITATION OF TRIGONELLINE FROM MIRABILIS JALAPA LINN. LEAVES AND ENHANCEMENT IN EXTRACTION YIELD FROM ULTRA FINE POWDER

International Journal of Current Pharmaceutical Research ◽

10.22159/ijcpr.2017v9i1.16611 ◽

2016 ◽

Vol 9 (1) ◽

pp. 62 ◽

Cited By ~ 2

Author(s):

Padma S. Sathe ◽

Vidya V. Dighe

Keyword(s):

Method Development ◽

Fine Powder ◽

Volume Ratio ◽

Hplc Method ◽

Extraction Yield ◽

Column Temperature ◽

Methanolic Extracts ◽

Mirabilis Jalapa ◽

Jet Milling ◽

Development And Validation

Objective: Development and validation of a simple and reliable HPLC method for determination of an alkaloid, trigonelline, in the methanolic extract of Mirabilis jalapa Linn. leaves and comparing the extraction yields of trigonelline from micro powder and ultrafine powder.Methods: The quantitation of trigonelline was carried out on a Phenomenex (Luna 5 U RP C8 (2) column, 25 cm x 4.6 mm, i.d. 5 µm), using mobile phase comprising of distilled water containing HCl (pH adjusted to 3.5) and methanol in the volume ratio of 70:30, which was delivered at the flow rate of 0.5 ml per min, at 35 °C column temperature. The detection and quantitation of trigonelline were carried out using PDA detector at the wavelength λ=264 nm.Ultra-fine powder of Mirabilis jalapa Linn. was prepared using simple stepwise powdering method. The dried leaves of Mirabilis jalapa Linn. were ground using ice jacketed domestic mixer. This powder was sieved through a BSS 85 mesh sieve and considered as a micro powder. Further fine grinding was done by jet milling, followed by ball milling. This powder was considered as an ultra-fine powder.Results: The proposed HPLC method for quantitation of trigonelline from dried leaf powder of Mirabilis jalapa Linn. is rapid, simple, accurate and precise.Conclusion: The amount of trigonelline obtained using methanolic extracts of Mirabilis jalapa Linn. Ultra-fine powder and the micro powder was found to be 1.1103 mg/g and 0.7258 mg/g respectively.

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