An Investigation of the use of Stearic Acid as a Process Control Agent in High Energy Ball Milling of Nb-Al and Ni-Al Powder Mixtures

High energy ball milling was performed on a mixture of titanium and aluminum elemental powders with a composition of Ti -48(at.%) Al . Stearic acid was added to this powder mixture as a process control agent (PCA) to study its effect on the microstructure evolution and crystallite size of the milled powder after various milling times. Phase compositions and morphology of the milled powders were evaluated using X-ray diffraction and scanning electron microscopy. Crystallite sizes of milled powders were determined by Cauchy-Gaussian approach using XRD profiles. It was shown that addition of 1wt.% of stearic acid not only minimizes the adhesion of milling product to the vial and balls, but also reduces its crystallite sizes. It has also a marked effect on the morphology of the final product.

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Facile synthesis of Ti3SiC2 powder by high energy ball-milling and vacuum pressureless heat-treating process from Ti–TiC–SiC–Al powder mixtures

Ceramics International ◽

10.1016/j.ceramint.2011.10.038 ◽

2012 ◽

Vol 38 (3) ◽

pp. 2027-2033 ◽

Cited By ~ 28

Author(s):

Meichao Peng ◽

Xiaoliang Shi ◽

Zhiwei Zhu ◽

Mang Wang ◽

Qiaoxin Zhang

Keyword(s):

Ball Milling ◽

Heat Treating ◽

High Energy ◽

High Energy Ball Milling ◽

Facile Synthesis ◽

Powder Mixtures ◽

Energy Ball ◽

Al Powder

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An Investigation on the Mechanical Alloying of TiFe Compound by High-Energy Ball Milling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.660-661.329 ◽

2010 ◽

Vol 660-661 ◽

pp. 329-334 ◽

Cited By ~ 5

Author(s):

Railson Bolsoni Falcão ◽

Edgar Djalma Campos Carneiro Dammann ◽

Cláudio José da Rocha ◽

Ricardo Mendes Leal Neto

Keyword(s):

Ball Milling ◽

High Energy ◽

High Energy Ball Milling ◽

Low Density Polyethylene ◽

Low Density ◽

Powder Mixtures ◽

Milling Parameters ◽

Process Route ◽

Partial Formation ◽

Energy Ball

This work reports the efforts to obtain TiFe intermetallic compound by high-energy ball milling of Ti and Fe powder mixtures. This process route has been used to provide a better hydrogen intake in this compound. Milling was carried out in a SPEX mill at different times. Strong adherence of material at the vial walls was seen to be the main problem at milling times higher than 1 hour. Attempts to solve this problem were accomplished by adding different process control agents, like ethanol, stearic acid, low density polyethylene, benzene and cyclohexane at variable quantities and keeping constant other milling parameters like ball to powder ration and balls size. Better results were attained with benzene and cyclohexane, but with partial formation of TiFe compound even after a heat treatment (annealing) of the milled samples.

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Synthesis by High-Energy Ball Milling of MgH2-TiFe Composites for Hydrogen Storage

Materials Science Forum ◽

10.4028/www.scientific.net/msf.899.13 ◽

2017 ◽

Vol 899 ◽

pp. 13-18 ◽

Cited By ~ 2

Author(s):

Ricardo Mendes Leal Neto ◽

Rafael de Araújo Silva ◽

Ricardo Floriano ◽

Graziele Cristina Seco Coutinho ◽

Railson Bolsoni Falcão ◽

...

Keyword(s):

Ball Milling ◽

Hydrogen Absorption ◽

Hydrogen Desorption ◽

High Energy ◽

Control Agent ◽

High Energy Ball Milling ◽

Absorption Kinetics ◽

Particle Size Reduction ◽

Milled Sample ◽

Energy Ball

The aim of this work is to investigate the influence of some processes variables on the microstructure and hydrogen absorption kinetics of MgH2 - X wt.% TiFe composites. Samples were synthesized by high-energy ball milling in a planetary (X = 40, 50, 60) and shaker mill (X = 40) under high-purity argon atmosphere. Commercial MgH2 instead of Mg powder was used in order to reduce adherence on the vial and balls. TiFe powder was previously produced by ball milling a mixture of TiH2 and Fe powders followed by a reaction synthesis at 600oC. Milled composites samples were characterized by XRD and SEM analysis. Milling time was preliminary investigated (X = 40) in the planetary ball mill (6 to 36h). TiFe particle size reduction was shown to be difficult since they are surrounded by MgH2 matrix. Strong particle reduction was obtained by using a shaker mill only for 2 hours and adding cyclohexane as process control agent. No reaction between MgH2 and TiFe compound was observed in any milled sample. Hydrogen absorption kinetics measurements of the as-milled samples were conducted on an Sieverts' type apparatus at room temperature after hydrogen desorption at 350oC under vacuum. The best hydrogen kinetics (3 wt% at the first hour) was attained by the planetary milled sample (36 h). Higher hydrogen capacity was observed for the sample milled in the shaker mill (4.0 wt.%), but only after 13h.

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Structure and Thermal Stability of Nanostructured Iron-doped Zirconia Prepared by High-energy Ball Milling

Journal of Materials Research ◽

10.1557/jmr.1999.0183 ◽

1999 ◽

Vol 14 (4) ◽

pp. 1343-1352 ◽

Cited By ~ 77

Author(s):

J. Z. Jiang ◽

F. W. Poulsen ◽

S. Mørup

Keyword(s):

Ball Milling ◽

Unit Cell Volume ◽

High Energy ◽

High Energy Ball Milling ◽

Iron Ions ◽

Monoclinic Zirconia ◽

Maximum Solubility ◽

Powder Mixtures ◽

Energy Ball ◽

Thermal Stability Of

Fully stabilized cubic zirconia doped with iron oxide has been synthesized by high-energy ball milling from powder mixtures of monoclinic zirconia and hematite. It is found that the iron ions dissolved in cubic ZrO2 are in substitutional positions with a maximum solubility of approximately 18.5 mol% α–Fe2O3. The unit-cell volume of the cubic ZrO2 phase decreases with increasing iron content. During heating the cubic-to-tetragonal transition occurs at approximately 827 °C and the tetragonal-to-monoclinic transition seems to be absent at temperatures below 950 °C. During cooling the tetragonal-to-monoclinic transition occurs at 900–1100 °C.

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