Structural evolution during heat treatment of mechanically alloyed Al–Cu–Fe–(Si) alloys

Fe-10Cr-5Y2O3 powders were mechanically alloyed using a high energy horizontal ball-mill apparatus, and the effect of heat treatment on the behavior of nano-sized oxide particles formed in the mechanically alloyed Fe-10Cr-5Y2O3 powders was investigated. Elongated Cr-rich and Y-rich oxides were observed in the mechanically alloyed powders. During the heating of these powders above 700 °C, the elongated Cr-rich oxides were dramatically changed to a near- spherical morphology. Cubic-Y2O3, monoclinic-Y2O3 and YFeO3 phases were also found after heat treatment at 1150 °C for 1h, indicating that the Y-rich oxide phase was transformed to the cubic-Y2O3, monoclinic-Y2O3 and YFeO3 ones. It is thus concluded that both a morphological change of Cr-rich oxide and a phase transformation of Y-rich oxide during the heating of mechanically alloyed powders could be mainly attributed to extremely high energy, accumulated by the mechanical alloying process.

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Synthesis and grain growth kinetics of in-situ FeAl matrix nanocomposites (II): Structural evolution and grain growth kinetics of mechanically alloyed Fe-Al-Ti-B composite powder during heat treatment

Transactions of Nonferrous Metals Society of China ◽

10.1016/s1003-6326(08)60012-6 ◽

2008 ◽

Vol 18 (1) ◽

pp. 66-71 ◽

Cited By ~ 12

Author(s):

Rong REN ◽

Yu-cheng WU ◽

Wen-ming TANG ◽

Feng-tao WANG ◽

Tu-gen WANG ◽

...

Keyword(s):

Heat Treatment ◽

Grain Growth ◽

Growth Kinetics ◽

Composite Powder ◽

Structural Evolution ◽

Mechanically Alloyed ◽

Grain Growth Kinetics ◽

Matrix Nanocomposites ◽

Kinetics Of

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Intermetallic Effects on the Ductility of Sintered Aluminium

Materials Science Forum ◽

10.4028/www.scientific.net/msf.587-588.380 ◽

2008 ◽

Vol 587-588 ◽

pp. 380-384

Author(s):

Jesus Cintas ◽

José A. Rodríguez ◽

Francicso Gomez Cuevas ◽

José M. Gallardo

Keyword(s):

Heat Treatment ◽

Particle Size ◽

Intermetallic Particle ◽

Quantitative Metallography ◽

Mechanically Alloyed ◽

Aluminium Powder ◽

Attrition Milling ◽

Different Temperatures ◽

Alloyed Aluminium ◽

Milled Powders

Mechanically alloyed aluminium powder was prepared by attrition-milling for 10 hours in the presence of a wax. Milled powders were annealed in vacuum at different temperatures (500, 575, 600, 625 and 650°C). Compacts were consolidated starting from unannealed and from 600°Cannealed powders. Studies by SEM microfractography and quantitative metallography, to investigate the influence of Fe-Al intermetallics on compacts fracture, have been carried out. It is concluded that fracture takes place at regions where the area occupied by the intermetallics is high and intermetallics particles are big. Intermetallic particle size can be controlled by an appropriated heat treatment.

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Structural Evolution in Wet Mechanically Alloyed Co-Fe-(Ta,W)-B Alloys

Metals ◽

10.3390/met11050800 ◽

2021 ◽

Vol 11 (5) ◽

pp. 800

Author(s):

Vladimír Girman ◽

Maksym Lisnichuk ◽

Daria Yudina ◽

Miloš Matvija ◽

Pavol Sovák ◽

...

Keyword(s):

Structural Changes ◽

Magnetic Measurements ◽

Structural Evolution ◽

High Energy ◽

Control Agent ◽

X Ray Diffraction ◽

Mechanically Alloyed ◽

X Ray ◽

Transmission Electron ◽

X Ray Absorption

In the present study, the effect of wet mechanical alloying (MA) on the glass-forming ability (GFA) of Co43Fe20X5.5B31.5 (X = Ta, W) alloys was studied. The structural evolution during MA was investigated using high-energy X-ray diffraction, X-ray absorption spectroscopy, high-resolution transmission electron microscopy and magnetic measurements. Pair distribution function and extended X-ray absorption fine structure spectroscopy were used to characterize local atomic structure at various stages of MA. Besides structural changes, the magnetic properties of both compositions were investigated employing a vibrating sample magnetometer and thermomagnetic measurements. It was shown that using hexane as a process control agent during wet MA resulted in the formation of fully amorphous Co-Fe-Ta-B powder material at a shorter milling time (100 h) as compared to dry MA. It has also been shown that substituting Ta with W effectively suppresses GFA. After 100 h of MA of Co-Fe-W-B mixture, a nanocomposite material consisting of amorphous and nanocrystalline bcc-W phase was synthesized.

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Structural changes in mechanically alloyed copper-titanium-boron during heat treatment

Metal Powder Report ◽

10.1016/0026-0657(94)91894-5 ◽

1994 ◽

Vol 49 (4) ◽

pp. 51

Keyword(s):

Heat Treatment ◽

Structural Changes ◽

Mechanically Alloyed

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Influence of Preparation Process on Microstructure, Critical Current Density and Tc of MgB2/Fe/Cu Wires

Materials Science Forum ◽

10.4028/www.scientific.net/msf.546-549.2031 ◽

2007 ◽

Vol 546-549 ◽

pp. 2031-2034

Author(s):

Y.F. Wu ◽

G. Yan ◽

J.S. Li ◽

Y. Feng ◽

Shao Kai Chen ◽

...

Keyword(s):

Heat Treatment ◽

Current Density ◽

Rolling Process ◽

High Energy ◽

Transport Current ◽

Post Heat Treatment ◽

Mechanically Alloyed ◽

Mgb2 Wires ◽

Powder In Tube ◽

Transport Current Density

The powder-in-tube MgB2 wires were prepared by high energy milling of Mg and B powder. The powder was not mechanically alloyed for 2h short milling time. However, the MgB2 grains in wires were very small (20~100nm) and resemble the dimple after post-heat treatment. The clear evidence for transcrystlline fracture was observed. It indicated that the grain connection was greatly improved and the fluxing pinning was significantly enhanced. Another point to view was no intermediate annealing during the whole rolling process. The influence of the post-heat treatment on the transport current density was studied. Despite the lower Tc of about 35K, the transport current density reached to 3×104A/cm2 at 15K and 3.5T for wires sintered at 700°C.

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