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

2012 ◽  
Vol 59 (2) ◽  
Author(s):  
Nurulhuda Bashirom ◽  
Hazni Fazliana Kassim
Keyword(s):  
Stainless Steel ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Weight Ratio ◽  
Copper Matrix ◽  
High Energy ◽  
Milling Process ◽  
Nominal Composition ◽  
Peak Broadening

This paper presents a study on the effect of milling time on the synthesis of Cu-WC nanocomposites by mechanical alloying (MA). The Cu-WC nanocomposite with a 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 the composition Cu-34.90 wt.% W-2.28 wt.% C. The powders were milled in the different milling times; 16 hours, 32 hours, and 48 hours at rotational speed of 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 indicated the formation of WC after milling for 32 hours, and the peak broadening was observed at higher milling time. From SEM observations, the particle size of Cu-25 vol.% WC composites was gradually refined with increasing milling time until the homogenous microstructure was obtained at 48 hours of milling, even though there were still some unreacted W particles existed in the matrix. Increasing milling time resulted in smaller crystallite size and higher lattice strain of Cu. The overall result demonstrates that the longer milling time can be used to achieve WC reinforced copper matrix nanocomposite.

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.

scholarly journals Recycling Chips of Stainless Steel Using a Full Factorial Design

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 842
Author(s):  
Claudiney Mendonça ◽  
Patricia Capellato ◽  
Emin Bayraktar ◽  
Fábio Gatamorta ◽  
José Gomes ◽  
...  
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Duplex Stainless Steel ◽  
Vanadium Carbide ◽  
Milling Time ◽  
Rotation Speed ◽  
Weight Ratio ◽  
High Energy ◽  
Milling Process ◽  
Full Factorial

The aim of this study was to provide an experimental investigation on the novel method for recycling chips of duplex stainless steel, with the addition of vanadium carbide, in order to produce metal/carbide composites from a high-energy mechanical milling process. Powders of duplex stainless steel with the addition of vanadium carbide were prepared by high-energy mechanical ball milling utilizing a planetary ball mill. For this proposal, experiments following a full factorial design with two replicates were planned, performed, and then analyzed. The four factors investigated in this study were rotation speed, milling time, powder to ball weight ratio and carbide percentage. For each factor, the experiments were conducted into two levels so that the internal behavior among them could be statistically estimated: 250 to 350 rpm for rotation speed, 10 to 50 h for milling time, 10:1 to 22:1 for powder to ball weight ratio, and 0 to 3% carbide percentage. In order to measure and characterize particle size, we utilized the analysis of particle size and a scanning electron microscopy. The results showed with the addition of carbide in the milling process cause an average of reduction in particle size when compared with the material without carbide added. All the four factors investigated in this study presented significant influence on the milling process of duplex stainless steel chips and the reduction of particle size. The statistical analysis showed that the addition of carbide in the process is the most influential factor, followed by the milling time, rotation speed and powder to ball weight ratio. Significant interaction effects among these factors were also identified.

Evaluating the morphology and distribution uniformity of AZ91D-SiC composite powder produced from magnesium chips by mechanical milling and alloying method

2021 ◽  
pp. 095440542110406
Author(s):  
Vahid Pouyafar ◽  
Ramin Meshkabadi
Keyword(s):  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Composite Powder ◽  
Milling Time ◽  
Particle Distribution ◽  
Weight Ratio ◽  
High Energy ◽  
Milling Process ◽  
Xrd Pattern ◽  
Distribution Uniformity

The AZ91D-SiC composite powder was produced from machining chips using the mechanical milling and alloying processes as an effective recycling method. The mechanical milling and alloying were conducted in a high-energy planetary ball mill. The effects of milling time and ball-to-powder weight ratio (BPR) on the morphology, distribution uniformity, and powder yield were evaluated. In the mechanical milling process, the four stages of chip milling were investigated. The optimum conditions of the milling were equal to milling for 10 h and a BPR of 25:1. The powder yield was at its maximum value and did not change much by changing the milling conditions. In the mechanical alloying, a higher BPR had a more significant effect on the uniform distribution of the particles compared to a higher milling time. The uniformity of the particle distribution is higher for 5 h alloying and a BPR of 20:1. A new peak in the XRD pattern of the composite powder obtained did not appear during the mechanical alloying process. It was observed that the amount of reinforcement phase has little effect on the particle size of the composite powder, while the particle distribution was improved by reducing it up to 40%.

scholarly journals Effect of Milling Parameters on the Development of a Nanostructured FCC–TiNb15Mn Alloy via High-Energy Ball Milling

Metals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1225
Author(s):  
Cristina García-Garrido ◽  
Ranier Sepúlveda Sepúlveda Ferrer ◽  
Christopher Salvo ◽  
Lucía García-Domínguez ◽  
Luis Pérez-Pozo ◽  
...  
Keyword(s):  
Mechanical Alloying ◽  
Ball Mill ◽  
Milling Time ◽  
High Energy ◽  
Planetary Mill ◽  
Nominal Composition ◽  
Mechanically Alloyed ◽  
Milling Parameters ◽  
Energy Ball ◽  
Full Conversion

In this work, a blend of Ti, Nb, and Mn powders, with a nominal composition of 15 wt.% of Mn, and balanced Ti and Nb wt.%, was selected to be mechanically alloyed by the following two alternative high-energy milling devices: a vibratory 8000D mixer/mill® and a PM400 Retsch® planetary ball mill. Two ball-to-powder ratio (BPR) conditions (10:1 and 20:1) were applied, to study the evolution of the synthesized phases under each of the two mechanical alloying conditions. The main findings observed include the following: (1) the sequence conversion evolved from raw elements to a transitory bcc-TiNbMn alloy, and subsequently to an fcc-TiNb15Mn alloy, independent of the milling conditions; (2) the total full conversion to the fcc-TiNb15Mn alloy was only reached by the planetary mill at a minimum of 12 h of milling time, for either of the BPR employed; (3) the planetary mill produced a non-negligible Fe contamination from the milling media, when the highest BPR and milling time were applied; and (4) the final fcc-TiNb15Mn alloy synthesized presents a nanocrystalline nature and a partial degree of amorphization.

scholarly journals Influence of the Milling Time on Mechanical and Magnetic Properties of Cu90Co5Ni5 Alloy Obtained by Mechanical Alloying

2009 ◽  
Vol 423 ◽  
pp. 119-124 ◽  
Author(s):  
Marta López ◽  
M. Elena Gómez ◽  
David Reyes ◽  
K. Ramam ◽  
Ramalinga V. Mangalaraja ◽  
...  
Keyword(s):  
Magnetic Properties ◽  
Mechanical Alloying ◽  
Magnetic Particles ◽  
Milling Time ◽  
Copper Matrix ◽  
Milling Process ◽  
Sintering Behavior ◽  
Powder Samples ◽  
Xrd Patterns ◽  
Sintered Alloys

The structure, mechanical and magnetic properties of Cu90Co5Ni5 alloys produced by mechanical alloying and subsequent cold consolidation and sintering behavior, have been investigated. A system of small Co and Ni magnetic particles embedded in the non-magnetic copper matrix were prepared through a mechanical milling process by using a planetary ball mill under argon atmosphere for 20 to 60 h. The morphology and particles size, phase formation and chemical composition of the alloyed powder samples for each milling time were characterized by scanning electron microscope and powder X-ray diffraction techniques, respectively. After milling for 60 h, a supersaturated solid solution with coercive field Hc with maximum value of 235Oe was obtained. The continuous decreasing trend of saturation magnetization (Ms) with increasing of milling time can be explained by the reduction of copper oxide by (CoNi) oxide formation, confirmed by powder XRD patterns. The XRD analyses of the as-milled samples revealed that the Bragg peaks of FCC-Co changed partially to HCP-Co on increasing the milling time. Cu90Co5Ni5 powders cold consolidated and sintered at 650°C for 1h segregated mainly into two-phases of mixed (fcc,hc)-Co and fcc-CuNi. After sintering, the mechanical properties for 60h milling reached its optimum, 26HV in hardness corresponding to 250MPa as compressive strength. TEM microanalysis of sintered alloys revealed Co cluster of 2 to 5 nm in size separated each one by 10 to 20 nm in size. The variation of magnetic properties and its dependence on structural-precipitation change with milling time are discussed.

Microstructural and Magnetic Properties of Nanostructured Fe65Co35 Powders Prepared by Mechanical Alloying

2013 ◽  
Vol 829 ◽  
pp. 778-783 ◽  
Author(s):  
Mohsen Razi ◽  
Ali Ghasemi ◽  
Gholam Hossein Borhani
Keyword(s):  
Magnetic Properties ◽  
Mechanical Alloying ◽  
Milling Time ◽  
Cooling System ◽  
Average Particle Size ◽  
Weight Ratio ◽  
Lattice Parameter ◽  
Milling Process ◽  
Protective Atmosphere ◽  
Average Particle

Nanostructured Fe65Co35 alloy powders were fabricated by mechanical alloying in an attritor mill with different milling times. The milling process carried out in speed of 350 rpm, with 20:1 ball to powder weight ratio and under argon protective atmosphere. A continuous cooling system applied to avoid increasing temperature during the milling. The effect of milling time on structural and magnetic properties investigated by X-ray diffraction, scanning electron microscopy and vibration sample magnetometer. According to the obtained results, nanostructured Fe65Co35 solid solution powders resulted with an average particle size of 400 nm and crystallite size of 6.8 nm by milling for 20 hours. With increasing the milling time, the lattice parameter decreased and the lattice strain increased for Fe65Co35 powders. The maximum saturation magnetization with 1311 emu/cc value and the minimum coercivity with 22 Oe value occurs after milling for 15 hours.

scholarly journals Influence of Oxide Additions in Cu-Co-Fe Composite Powders Obtained by Mechanical Alloying

2014 ◽  
Vol 783-786 ◽  
pp. 1548-1553
Author(s):  
Núria Llorca-Isern ◽  
Cristina Artieda-Guzman ◽  
Jose Alberto Vique ◽  
Antoni Roca
Keyword(s):  
Mechanical Alloying ◽  
Crystallite Size ◽  
Composite Powder ◽  
Milling Time ◽  
High Energy ◽  
Milling Process ◽  
Composite Powders ◽  
Ceramic Particles ◽  
Pure Cu ◽  
Ceramic Reinforcement

Nanocrystalline composite powders were prepared by mechanical alloying of pure Cu, Fe and Co as metallic major part and Al2O3 or Fe2O3 or SiO2 as ceramic reinforcement in a high-energy ball mill. Alloys of the copper-iron-cobalt system are promising for the development of new materials and applications. Cu-Fe-Co is used in different applications depending on the properties required. These can be related for example to toughness when used as rock cutting tool, to magnetic and electric properties for microelectronics or to chemical behaviour when used as catalysts in bioalcohol production industry. The objective of the present study is to contribute to understanding how and to which amount the ceramic reinforcement affects the properties for which this Cu-Fe-Co system is used as well as to envisage other less frequently uses for the composite powders. Structural and magnetic transformations occurring in the material during milling were studied with the use of X-ray diffraction, scanning quantum induction device (SQUID) and magnetic force microscopy (MFM). In mechanical alloying the transformations depend upon milling time. The results showed that milling the elemental powders of Cu-Fe-Co in the mass proportion of 50:25:25 respectively for times up to 10h leads to the progressive dissolution of Fe and Co atoms into FCC Cu and the final product of the MA process was the nanocrystalline Cu containing Fe and Co with a mean crystallite size (from coherent crystal size determination by diffraction) of 20 nm aprox. When ceramic particles are milled together with the metals (at proportions of the oxides between 1-10%) this mechanism is retarded. On the other hand, the lowest mean crystallite size is reached without ceramic particles in the milling process. However the composite powder produced in all the cases stabilized similar lowest crystallite size between 45-50 nm. Mechanically alloyed metallic-ceramic composite powder showed lower saturation magnetization than the metallic system but enhanced coercive field (significantly for hematite reinforcement). All the studied systems are intermediate ferromagnetics (Hc≈104 A/m). Milling time significantly affects the structure, composition and properties for both metallic and composite systems.

THE EFFECT OF Mn ON α TO γ TRANSFORMATION IN THE NANOSTRUCTURED HIGH NITROGEN Fe-Cr-Mn STAINLESS STEEL PRODUCED BY MECHANICAL ALLOYING

2012 ◽  
Vol 05 ◽  
pp. 49-57
Author(s):  
FARIBA TEHRANI ◽  
MOHAMMAD HASAN ABBASI ◽  
MOHAMMAD ALI GOLOZAR ◽  
MASOUD PANJEPOUR
Keyword(s):  
Grain Size ◽  
Stainless Steel ◽  
Mechanical Alloying ◽  
Milling Time ◽  
High Energy ◽  
Nitrogen Atmosphere ◽  
Transformation Rate ◽  
X Ray Diffraction ◽  
High Nitrogen ◽  
Xrd Patterns

In this study, the effect of Mn on α to γ transformation in the nanostructured high nitrogen Fe -18 Cr - xMn stainless steel produced by mechanical alloying (MA) was investigated. MA was performed under nitrogen atmosphere using a high-energy planetary ball mill. X- ray diffraction (XRD) patterns of produced samples showed that α to γ transformation starts after 20 hours of milling and propagates by increasing the milling time. Completion of this phase transformation occurred in the Fe -18 Cr -8 Mn sample after 100 hours of milling. But, in the Fe -18 Cr -7 Mn sample, some α phase remained even after 150 hours of milling. Also, nitrogen analysis revealed that nitrogen solubility in the milled powders increased significantly by increasing the milling time, and ultimately reached 1wt%. This is believed to be due to the increase of the lattice defects and development of nanostructure through MA. Variations in grain size and internal lattice strain versus milling time in both cases showed that the critical ferrite grain size for austenite nucleation was lower than 10nm. Moreover, a lower transformation rate was found in samples containing lower Mn content.

Effect of the Reinforcement Volume Fraction on Mechanical Alloying of AA2124 – SiC Composite

2010 ◽  
Vol 660-661 ◽  
pp. 317-324 ◽  
Author(s):  
Grazziani Maia Candido ◽  
Vanessa Guido ◽  
Gilbert Silva ◽  
Kátia Regina Cardoso
Keyword(s):  
Aluminum Alloy ◽  
Mechanical Alloying ◽  
Crystallite Size ◽  
Alloy Powder ◽  
Milling Time ◽  
Volume Fraction ◽  
High Energy ◽  
Al Alloy ◽  
Peak Broadening ◽  
Aluminum Alloy Powder

Mixtures of AA2124 aluminum alloy powder and SiC particles at volume fractions of 10 vol.% and 20 vol.% were milled in a high energy planetary ball mill under an argon atmosphere, for times of 2.5h to 60 h, aiming to produce Al alloy-SiC nanocomposites. Optical microscopy (MO) and scanning electron microscopy (SEM) were used to evaluate the morphological and microstructural evolution of the powder composite, occurred during mechanical alloying. The crystallite size was determined using the Williamson-Hall method to analyze the X-ray peak broadening. It was observed that increasing the volume fraction of SiC, the mechanical alloying stages were accelerated: a finer composite powder was obtained at a shorter milling time as well as the morphology of the particles became more equiaxed. The XRD analysis showed the reduction of crystallite size of the aluminum alloy matrix with increasing milling time and that this effect is more pronounced with high volume fraction of SiC. The results show that the increase in the volume fraction of reinforcement particles increases the work hardening and fracture occurrence in the aluminum alloy powder during the milling, affecting the structural evolution of the composite.

Ti-Al-Zr-B-Y Amorphous Alloy Powders Prepared by Mechanical Alloying

2015 ◽  
Vol 1095 ◽  
pp. 222-225 ◽  
Author(s):  
Yu Ying Zhu ◽  
Yun Hua He ◽  
Qiang Li
Keyword(s):  
Stainless Steel ◽  
Amorphous Alloy ◽  
Mechanical Alloying ◽  
Rotation Rate ◽  
Milling Time ◽  
High Energy ◽  
Glass Forming Ability ◽  
Argon Atmosphere ◽  
Glass Forming ◽  
Energy Ball

Mechanical alloying (MA) is used to prepare amorphous alloy powders. The experiments were performed by a high energy ball milling device using stainless steel vessels and balls under argon atmosphere at a rotation rate of 450 r/min. B and Y were used as the minor additions to prepare new quaternary or complex amorphous alloy powders. Ti50Al(47-x-y)Zr3BxYy(x=0, 0.6, y=0, 0.2) amorphous alloy powders were successively obtained. The milled amorphous alloy powders were characterized by XRD, SEM and DSC. Ti50Al47Zr3amorphous alloy powders were obtained after milled 50h. The milling time needed to obtain complete amorphous alloy for Ti50Al46.4Zr3B0.6, Ti50Al46.8Zr3Y0.2and Ti50Al46.2Zr3B0.6Y0.2are 40h, 35h and 30h, respectively. Minor additions of B and Y decreases the milling time for preparing amorphous alloy. SEM shows that B and Y can refine the grain of the amorphous alloy powders. DSC shows that minor substitution of 0.6at.%B or 0.2at.%Y can increase the glass forming ability (GFA) for the TiAl based alloys.

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