Formation of nanocrystalline and amorphization phase of Fe–Dy2O3 powder mixtures induced by ball milling

2016 ◽  
Vol 32 (3) ◽  
pp. 575-581 ◽  
Author(s):  
Jinhua Huang ◽  
Junqiang Lu ◽  
Guang Ran ◽  
Nanjun Chen ◽  
Peidong Qu
Keyword(s):  
Ball Milling ◽  
Powder Mixtures ◽  
Image Position

Abstract

Effect of Boron and Carbon Addition on the Phase Transformations during High-Energy Ball Milling and Subsequent Sintering of Si3N4+B and Si3N4+C Powder Mixtures

2016 ◽  
Vol 869 ◽  
pp. 58-63
Author(s):  
Luiz Otávio Vicentin Maruya ◽  
Bruna Rage Baldone Lara ◽  
Belmira Benedita de Lima ◽  
Vanessa Motta Chad ◽  
Gilberto Carvalho Coelho ◽  
...  
Keyword(s):  
Phase Transformations ◽  
Ball Milling ◽  
Weight Ratio ◽  
High Energy ◽  
Ceramic Composites ◽  
Nitrogen Atmosphere ◽  
Carbon Addition ◽  
Powder Mixtures ◽  
X Ray ◽  
Milled Powders

This study reports on effect of boron and carbon addition on the phase transformations during ball milling and subsequent sintering of Si3N4+B and Si3N4+C powder mixtures. Ball milling at room temperature was conducted using stainless steel vials (225 mL) and balls (19mm diameter), 300 rpm and a bal-to-powder weight ratio of 10:1. The as-milled powders were uniaxially compacted in order to obtain cylinder samples with 10 mm diameter, which were subsequently sintered under nitrogen atmosphere at 1500°C for 1h. Characterization of the as-milled powders and sintered samples was performed by X-ray diffraction, scanning electron microscopy, and energy dispersive spectrometry. Only peaks of Si3N4 were identified in X-ray diffractograms of as-milled Si3N4+B and Si3N4+C powders, suggesting that metastable structures were found during milling. After sintering at 1500°C for 1h, the Si3N4+BN and Si3N4+SiC ceramic composites were formed from the mechanically alloyed Si3N4+B and Si3N4+C powders.

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

2010 ◽  
Vol 660-661 ◽  
pp. 329-334 ◽  
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.

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

1999 ◽  
Vol 14 (4) ◽  
pp. 1343-1352 ◽  
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.

scholarly journals Microstructural Evolution, Thermodynamics and Kinetics of Mo-Tm2O3 Powder Mixtures during Ball Milling

2016 ◽  
Author(s):  
Yong Luo ◽  
Guang Ran ◽  
Nanjun Chen ◽  
Qiang Shen ◽  
Yaoli Zhang
Keyword(s):  
Solid Solution ◽  
Ball Milling ◽  
Microstructural Evolution ◽  
Driving Force ◽  
Phase Evolution ◽  
Heat Of Mixing ◽  
Powder Mixtures ◽  
Thermodynamics And Kinetics ◽  
Transmission Electron ◽  
Kinetics Of

The microstructural evolution, thermodynamics and kinetics of Mo-21%Tm2O3 (mass fraction, %) powder mixtures during ball milling were investigated using X-ray diffraction and transmission electron microscopy. Ball milling induced Tm2O3 to be decomposed and then dissolved into Mo crystal. The supersaturated nanocrystalline solid solution of Mo (Tm, O) was obtained after 96 h of ball milling. The elements of Mo, Tm and O were distributed uniformly in the ball-milled particles. Based on the semi-experimental theory of Miedema, a thermodynamic model was developed to calculate the driving force of phase evolution. There was no chemical driving force to form a crystal solid solution of Tm atoms in Mo crystal or an amorphous phase because the Gibbs free energy for both processes was higher than zero. For Mo-21%Tm2O3, it was mechanical work, not negative heat of mixing, that provided the driving force to form supersaturated nanocrystalline Mo (Tm, O) solid solution.

scholarly journals Microstructural Evolution of Dy2O3-TiO2 Powder Mixtures during Ball Milling and Post-Milled Annealing

Materials ◽  
2016 ◽  
Vol 10 (1) ◽  
pp. 19 ◽  
Author(s):  
Jinhua Huang ◽  
Guang Ran ◽  
Jianxin Lin ◽  
Qiang Shen ◽  
Penghui Lei ◽  
...  
Keyword(s):  
Ball Milling ◽  
Microstructural Evolution ◽  
Tio2 Powder ◽  
Powder Mixtures
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