scholarly journals Optimization of milling speed and time in mechanical alloying of ferritic ODS steel through taguchi technique

2021 ◽  
Vol 12 ◽  
pp. 25
Author(s):  
Ganesan Dharmalingam ◽  
Murali Arun Prasad ◽  
Sachin Salunkhe
Keyword(s):  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Milling Time ◽  
Influencing Factor ◽  
Oxide Dispersion Strengthened ◽  
Amorphous Structure ◽  
Ods Steel ◽  
High Impurity ◽  
Selection Of ◽  
Milled Powders

The oxide dispersion strengthened (ODS) ferritic steels are one of the most important in fuel cladding materials for 4th Generation nuclear reactors because of their excellent mechanical properties such as irradiation resistance, swelling resistance, and elevated temperature tensile/compressive strength. Mechanical alloying (MA) is one of the most promising routes for developing nanocrystalline ferritic ODS steel materials. For the production of nanocrystalline ferritic ODS steel powders, the most influencing factor is the milling speed and milling time during the mechanical alloying process. With the improper selection of milling time and speed, the final milled powders become an amorphous structure consisting of high impurity inclusions in the microstructure, and strength was also affected. In order to overcome these drawbacks, the present investigation was taken into account for the selection of appropriate mechanical milling speed and time, which was optimized through Taguchi analysis followed by the MA process. The optimized mechanical milling speed and time of milled powders were characterized through X-Ray Diffraction Analysis (XRD) and Scanning Electron Microscope (SEM).

Influence of Mechanical Alloying Time on Morphology and Properties of 15Cr-ODS Steel Powders

2016 ◽  
Vol 35 (5) ◽  
pp. 473-477 ◽  
Author(s):  
Haijian Xu ◽  
Zheng Lu ◽  
Chunyan Jia ◽  
Danzhu Feng ◽  
Chunming Liu
Keyword(s):  
Mechanical Alloying ◽  
Vickers Hardness ◽  
Mechanical Milling ◽  
Milling Time ◽  
Oxide Dispersion Strengthened ◽  
Main Process ◽  
Powder Size ◽  
Ods Steel ◽  
Initial Stage ◽  
The Mean

AbstractOxide dispersion strengthened (ODS) ferritic steels are the leading candidates of fuel cladding for Generation IV nuclear reactors due to their excellent properties such as excellent radiation tolerance and high-temperature creep strength. Mechanical milling with the aim of a fine dispersion of oxides in the metal matrix becomes the main process for the production of ODS steels. In order to clarify the influence of milling time on the precursor powders for 15Cr-ODS steel, the morphology and properties of mechanical alloying (MA) powders with different milling time were investigated by scanning electron microscopy (SEM), laser diffraction particle size analyzer, X-ray diffraction (XRD) and Vickers hardness tester. The experimental results showed that the powder was fractured and welded with rotation and vibration of container during mechanical milling. The mean powder size increased (0–1 h) firstly then decreased (2–60 h). Extending milling time to 70 h, the mean powder size increased again. The grain size decreased quickly at the initial stage of milling process (0–2 h) then trended to reach a saturation value. The Vickers hardness increased rapidly at the initial stage of milling, then reached a saturation value.

scholarly journals Effect of Milling Time on Microstructure, Crystallite Size and Dielectric Properties of Srtio3 Ceramic Synthesized via Mechanical Alloying Method

2011 ◽  
Vol 364 ◽  
pp. 388-392
Author(s):  
Yick Jeng Wong ◽  
Hassan Jumiah ◽  
Mansor Hashim ◽  
Swee Yin Wong ◽  
Leow Chun Yan
Keyword(s):  
Dielectric Constant ◽  
Grain Size ◽  
Dielectric Properties ◽  
Mechanical Alloying ◽  
Crystallite Size ◽  
Single Phase ◽  
Milling Time ◽  
Average Grain Size ◽  
Average Lattice ◽  
Milled Powders

SrTiO3 sample has been successfully prepared by mechanical alloying (MA) method. The effect of milling time on microstructure, crystallite size and dielectric properties of SrTiO3 were studied. The results revealed that the mean crystallite size of milled powders decreased from 84.56 to 12.87 nm with increasing milling time. However, the average lattice strain of milled powders increased from 0.2 to 0.93% with increasing milling time. A single phase SrTiO3 could not be formed with milling alone and required annealing process. A transformation of anatase-TiO2 to rutile-TiO2 was observed at 16 h of milling. After the milled powders were subjected to sintering process at 1200°C, formation of single-phase SrTiO3-type cubic (Pm-3m) perovskite structure was observed. The peak intensities of the sintered SrTiO3 samples decreased as the milling time was increased. For microstructural observations, the average grain size of the sintered SrTiO3 sample milled for 8 h showed the largest. For dielectric measurements, the dielectric constant of the sintered SrTiO3 sample milled for 8 h showed the highest among others. This could be due to the largest grain size obtained for sintered SrTiO3 sample milled for 8 h. The decrease in the grain size with increasing milling time resulted to the decrease in dielectric constant.

Preparing Amorphous/Nanocrystalline TiNbZrTaFe Powder by Mechanical Alloying

2015 ◽  
Vol 816 ◽  
pp. 671-675
Author(s):  
Li Ming Zou ◽  
Yi Xiang Cai
Keyword(s):  
Mechanical Alloying ◽  
Milled Powder ◽  
Nanocrystalline Structure ◽  
Alloy System ◽  
Amorphous Structure ◽  
Liquid Region ◽  
Matrix Composites ◽  
Fe Content ◽  
Glass Matrix Composites ◽  
Milled Powders

(Ti69.7Nb23.7Zr4.9Ta1.7)100-xFex(x=0, 2, 6, and 10) nanocrystalline, nanocomposite and amorphous powders were synthesized by mechanical alloying from blended element powder. The structural transition for the milled powders was confirmed by X-ray diffraction (XRD). Results shows with the increasing Fe content in alloy system, the glass forming ability become larger. Only forx=10, it can obtain nearly completely amorphous structure with wide super cooled liquid region (△Tx=122 K). Forx=2 and 6, residual nanocrystals of the β-Ti structure dispersed in the amorphous matrix. Forx=0, the milled powder has full nanocrystalline structure. These as-milled powders offer the potential to fabricating the bulk glass material or nanocrystal/glass matrix composites by powder metallurgy for biomedical use.

Preparation of Y-Ti Bioxides Strengthened Fe-Cr Alloy by Mechanical Milling and Hot Pressing

2013 ◽  
Vol 475-476 ◽  
pp. 1307-1310
Author(s):  
Lei Dai ◽  
Ping Feng ◽  
Cai Hua Huang ◽  
Guang Wei Zhao
Keyword(s):  
Electron Microscope ◽  
Hot Pressing ◽  
Mechanical Milling ◽  
Milling Time ◽  
Operating Temperature ◽  
Oxide Dispersion Strengthened ◽  
X Ray Diffraction ◽  
Ferritic Alloys ◽  
X Ray ◽  
Transmission Electron

Oxide-dispersion-strengthened (ODS) ferritic alloys are fascinating materials for future fusion power reactors due to these materials would allow a substantial increase of the operating temperature. Y-Ti bioxides strengthened Fe-Cr alloy was produced by mechanical milling (MM) followed by hot pressing (HP). Microstructure changes of the mixed powders during mechanical milling and subsequent hot pressing were structurally characterized by means of scanning electron microscope (SEM), transmission electron microscope (TEM) and X-ray diffraction (XRD). The observations of structure of the mixed powders after MM indicated that the powders are fractured and welded with rotation and vibration of container during mechanical milling. And the particle size decreases with increasing milling time. Nanoscale Y-Ti bioxides were formed during the HP process.

Study on Amorphization of Mechanical Alloyed Cu50Zr40Ag10 Alloy

2011 ◽  
Vol 306-307 ◽  
pp. 1379-1382
Author(s):  
Lin Yan Xia ◽  
Yan Wang
Keyword(s):  
Mechanical Alloying ◽  
Amorphous Phase ◽  
Milling Time ◽  
Nearest Neighbor ◽  
Mechanical Stability ◽  
Amorphous Structure ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Short Range Ordering

The amorphization and crystallization of mechanical alloyed Cu50Zr40Ag10 alloy have been investigated using X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The results demonstrate that a full amorphous phase of Cu50Zr40Ag10 can be obtained through mechanical alloying. The amorphous phase begins to show the initial mechanical crystallization when the milling time is 108 h and subsequently the main milling product is still amorphous structure with increasing milling time up to 208 h. Therefore, the amorphous alloy exhibits the excellent mechanical stability during mechanical alloying. The nearest-neighbor distance of atoms firstly increases then reduces with the increasing milling time, indicating that there is a closely correlation between the initial crystallization behavior and short range ordering.

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%.

Mechanical properties of FeAlSi powders prepared by mechanical alloying from different initial feedstock materials

2019 ◽  
Vol 107 (2) ◽  
pp. 207 ◽  
Author(s):  
Jaroslav Čech ◽  
Petr Haušild ◽  
Miroslav Karlík ◽  
Veronika Kadlecová ◽  
Jiří Čapek ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Mechanical Alloying ◽  
Young’S Modulus ◽  
Milling Time ◽  
Young's Modulus ◽  
Element Model ◽  
X Ray Diffraction ◽  
X Ray ◽  
Powder Particles ◽  
Complete Homogenization

FeAl20Si20 (wt.%) powders prepared by mechanical alloying from different initial feedstock materials (Fe, Al, Si, FeAl27) were investigated in this study. Scanning electron microscopy, X-ray diffraction and nanoindentation techniques were used to analyze microstructure, phase composition and mechanical properties (hardness and Young’s modulus). Finite element model was developed to account for the decrease in measured values of mechanical properties of powder particles with increasing penetration depth caused by surrounding soft resin used for embedding powder particles. Progressive homogenization of the powders’ microstructure and an increase of hardness and Young’s modulus with milling time were observed and the time for complete homogenization was estimated.

Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

1988 ◽  
Vol 133 ◽  
Author(s):  
K. S. Kumar ◽  
S. K. Mannan
Keyword(s):  
High Temperature ◽  
Mechanical Alloying ◽  
Mechanical Milling ◽  
Room Temperature ◽  
Crystalline Compound ◽  
X Ray Diffraction ◽  
X Ray ◽  
Β Phase ◽  
Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

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