Mechanical Alloying of Fe-Nb-N with Different Ball to Powder Weight Ratio for the Formation of Fe-NbC Composite

2012 ◽  
Vol 620 ◽  
pp. 94-98 ◽  
Author(s):  
Siti Zalifah Md Rasib ◽  
Zuhailawati Hussain
Keyword(s):  
Mechanical Alloying ◽  
Weight Ratio ◽  
Milling Process ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Microstructure Characteristics ◽  
Scanning Electron Microscopic ◽  
Small Crystallite

Milling process through mechanical alloying method was performed on a powder mixture of Fe-80.11 wt%, Nb-17.62 wt% and C-2.26 wt% to produce Fe-NbC composite by in situ reaction. Ball to powder weight ratio parameter was selected since formation of phase and microstructure characteristics of this composite were expected to depend on ball collision event during milling. The as-milled and sintered Fe-NbC was characterized by X-ray diffraction (XRD) and Scanning Electron Microscopic (SEM). We found that formation of Fe-NbC by in situ required mechanical alloying of the mixture using 10:1 of ball to powder weight ratio to achieve small crystallite size and more homogeneous of NbC phase.

Effect of Milling Speed on the Synthesis of In-Situ Cu-25 Vol. % WC Nanocomposite by Mechanical Alloying

2012 ◽  
Vol 59 (2) ◽  
Author(s):  
Nurulhuda Bashirom ◽  
Nurzatil Ismah Mohd Arif
Keyword(s):  
Stainless Steel ◽  
Mechanical Alloying ◽  
Weight Ratio ◽  
High Energy ◽  
Milling Process ◽  
Nominal Composition ◽  
X Ray Diffraction ◽  
The Matrix ◽  
Steel Balls

This paper presents a study on the effect of milling speed on the synthesis of Cu-WC nanocomposites by mechanical alloying (MA). The Cu-WC nanocomposite with nominal composition of 25 vol.% of WC was produced in-situ via MA from elemental powders of copper (Cu), tungsten (W), and graphite (C). These powders were milled in the high-energy “Pulverisette 6” planetary ball mill according to composition Cu-34.90 wt% W-2.28 wt% C. The powders were milled in different milling speed; 400 rpm, 500 rpm, and 600 rpm. The milling process was conducted under argon atmosphere by using a stainless steel vial and 10 mm diameter of stainless steel balls, with ball-to-powder weight ratio (BPR) 10:1. The as-milled powders were characterized by X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). XRD result showed the formation of W2C phase after milling for 400 rpm and as the speed increased, the peak was broadened. No WC phase was detected after milling. Increasing the milling speed resulted in smaller crystallite size of Cu and proven to be in nanosized. Based on SEM result, higher milling speed leads to the refinement of hard W particles in the Cu matrix. Up to the 600 rpm, the unreacted W particles still existed in the matrix showing 20 hours milling time was not sufficient to completely dissolve the W.

Characterization of Ni75Mo25 Alloy Prepared by Mechanical Alloying and Heat Treatment

2013 ◽  
Vol 203-204 ◽  
pp. 394-397
Author(s):  
Joanna Panek ◽  
Bożena Bierska-Piech ◽  
Jolanta Niedbała
Keyword(s):  
Heat Treatment ◽  
Mechanical Alloying ◽  
Weight Ratio ◽  
Milling Process ◽  
Particle Sizes ◽  
X Ray Diffraction ◽  
Powder Synthesis ◽  
X Ray ◽  
Microscopy Techniques

The process of Ni75Mo25powder synthesis via mechanical alloying (MA) was studied. Process was carried out from pure elements: Ni and Mo with a particle size under 150 μm. A ball-to-powder weight ratio and the rotational speed were 5:1 and 500 rpm, respectively. Oxidation was reduced by milling under an argon atmosphere. The milling process was performed during up to 60 hours. X-ray diffraction (XRD) and scanning electron microscopy techniques have been used to investigate resulting products. It was found that the particle sizes decrease with the increase in milling time. The resulting powder consists of metastable Ni(Mo) and Mo(Ni) solid solutions. Milled Ni75Mo25 powder was subjected to heat treatment at temperature of 773K, 973K and 1173K. As a result of annealing the formation of Ni4Mo and NiMo intermetallic phases was observed.

Study of Nanostructured Cu Al Ni Alloy Produced by High Energy Mechanical Milling

2019 ◽  
Vol 56 ◽  
pp. 109-118
Author(s):  
Sofiane Mimouche ◽  
M. Azzaz
Keyword(s):  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Weight Ratio ◽  
High Energy ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ni Alloy ◽  
New Process ◽  
Scaning Electron Microscopy

Some years ago a new process was developed for the elaboration of alloys in order to overcome drawbacks observed in samples produced by conventional casting. In the present work are shown the results obtained by high energy mechanical milling for Cu-Al-Ni. the mechanical alloying powder Cu84Al12Ni4 (W%) was fabricated in high energy planetary ball milling at a speed of 250 r/min for various milling times (10 20 30 40 50 60 hours) the weight ratio of the balls of powder was 15 to 1. this mechanical alloying process is significantly modifying the characteristic of the powder, the recovered grains are ultimately compacted. The means used to study the different evolution are SEM Scaning Electron Microscopy, Differential thermal analysis DTA, X-ray Diffraction analysis and DRX in situ.

scholarly journals Preparation of Reswellable Amorphous Porous Celluloses through Hydrogelation from Ionic Liquid Solutions

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3249 ◽  
Author(s):  
Satoshi Idenoue ◽  
Yoshitaka Oga ◽  
Daichi Hashimoto ◽  
Kazuya Yamamoto ◽  
Jun-ichi Kadokawa
Keyword(s):  
Mechanical Properties ◽  
Ionic Liquid ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Liquid Solutions ◽  
Scanning Electron Microscopic ◽  
Porous Morphology ◽  
Scanning Electron

In this study, we have performed the preparation of reswellable amorphous porous celluloses through regeneration from hydrogels. The cellulose hydrogels were first prepared from solutions with an ionic liquid, 1-butyl-3-methylimidazolium chloride (BMIMCl), in different concentrations. Lyophilization of the hydrogels efficiently produced the regenerated celluloses. The powder X-ray diffraction and scanning electron microscopic measurements of the products suggest an amorphous structure and porous morphology, respectively. Furthermore, the pore sizes of the regenerated celluloses, or in turn, the network sizes of cellulose chains in the hydrogels, were dependent on the concentrations of the initially prepared solutions with BMIMCl, which also affected the tensile mechanical properties. It was suggested that the dissolution states of the cellulose chains in the solutions were different, in accordance with the concentrations, which representatively dominated the pore and network sizes of the above materials. When the porous celluloses were immersed in water, reswelling was observed to regenerate the hydrogels.

Effect of stretching speed on morphologies and properties of in situ microfibrillar POE/PLA composites

2020 ◽  
pp. 089270572093917
Author(s):  
Jing Sun ◽  
Anrong Huang ◽  
Shanshan Luo ◽  
Min Shi ◽  
Heng Luo ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Rheological Properties ◽  
Loss Modulus ◽  
Weight Ratio ◽  
Poly Lactic Acid ◽  
Electron Microscopic ◽  
Dynamic Rheological Properties ◽  
Scanning Electron Microscopic ◽  
Ethylene Octene Copolymer

In situ microfibrillar ethylene–octene copolymer (POE)/poly(lactic acid) (PLA) composites (MFCs) with different phase morphologies were prepared by controlling the stretching speed and maintaining the weight ratio of POE/PLA of 80/20. Four different stretching speeds were employed to study the effect of PLA microfibrillar morphology on tensile, crystalline, and rheological properties of MFCs. Scanning electron microscopic images revealed that the morphology of PLA phase was strongly influenced by stretching speed. MFCs with highest aspect ratio and smaller diameter of PLA microfibrils were obtained with a stretching speed of 60 rpm. The PLA microfibrils with high aspect ratio had the best reinforcement effect on MFCs. The dynamic rheological properties indicated that the MFCs achieved higher storage modulus and loss modulus at the stretching speed of 60 rpm.

Transformation of ferrihydrite to hematite: anin situinvestigation on the kinetics and mechanisms

2008 ◽  
Vol 72 (1) ◽  
pp. 217-220 ◽  
Author(s):  
H. P. Vu ◽  
S. Shaw ◽  
L. G. Benning
Keyword(s):  
High Resolution ◽  
Growth Mechanism ◽  
Elevated Temperatures ◽  
X Ray Diffraction ◽  
Electron Microscopic ◽  
Time Resolved ◽  
X Ray ◽  
Resolution Electron ◽  
Stage Process

AbstractThe kinetics and mechanisms of the transformation of 2-line ferrihydrite (FH) to hematite (HM), in the presence of Pb at elevated temperatures and high pH condition, were elucidated using synchrotron-based,in situenergy dispersive X-ray diffraction (EDXRD). The time-resolved diffraction data indicated that HM crystallization occurred via a two-stage process. Based on the EDXRD data, combined with high-resolution electron microscopic images, an aqueous-aided 2D growth mechanism is proposed for both HM crystallization stages.

scholarly journals Influence of the type of electrolyte on the morphological and crystallographic characteristics of lead powder particles

2013 ◽  
Vol 78 (9) ◽  
pp. 1387-1395 ◽  
Author(s):  
Nebojsa Nikolic ◽  
Vesna Maksimovic ◽  
Goran Brankovic ◽  
Predrag Zivkovic ◽  
Miomir Pavlovic
Keyword(s):  
X Ray Diffraction ◽  
Electron Microscopic ◽  
X Ray ◽  
Lead Powder ◽  
Scanning Electron Microscopic ◽  
Crystallographic Characteristics ◽  
Powder Particles ◽  
Primary Type ◽  
Secondary Type ◽  
Scanning Electron

Lead electrodeposition processes from the basic (nitrate) and complex (acetate) electrolytes were mutually compared by the scanning electron microscopic and the X-ray diffraction analysis of the produced powder particles. The shape of dendritic particles strongly depended on the type of electrolyte. The dendrites composed of stalk and weakly developed primary branches (the primary type) were predominantly formed from the basic electrolyte. The ramified dendrites composed of stalk and of both primary and secondary branches (the secondary type) were mainly formed from the complex electrolyte. In the both type of powder particles Pb crystallites were predominantly oriented in the (111) plane. Formation of powder particles of the different shape with the strong (111) preferred orientation was discussed and explained by the consideration of the general characteristics of the growth of a crystal in the electrocrystallization processes.

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