Effect of pressure and treatment temperature on the structural evolution of mechanically alloyed Ti(W)(C,N)–Al admixes in boron nitride

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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Production of alumo-matrix composite material modified by nanostructured cubic boron nitride

Proceedings of the National Academy of Sciences of Belarus Physical-Technical Series ◽

10.29235/1561-8358-2018-63-3-271-279 ◽

2018 ◽

Vol 63 (3) ◽

pp. 271-279

Author(s):

P. A. Vityaz ◽

V. T. Senyut ◽

M. L. Kheifetz ◽

A. G. Kolmakov

Keyword(s):

High Pressure ◽

Aluminum Alloy ◽

Boron Nitride ◽

Cubic Boron Nitride ◽

Aluminum Matrix ◽

Treatment Temperature ◽

Chemical Affinity ◽

High Temperature Annealing ◽

High Pressure And Temperature ◽

Primary Particles

The structure and microhardness of an aluminum alloy with additives of nanostructured cubic boron nitride (cBN) after treatment under high pressure and temperature are investigated. А nanostructured powder of cBN with primary particles within 50–200 nm is used as a filler. A preliminary chemical-thermal modifying of the nanostructured cBN, which consists in its high-temperature annealing in the temperature range of 750–950 °C in a medium of aluminum-contai ning compounds, is carried out to increase the chemical affinity of the nanostructured cBN to the aluminum matrix. It is shown that the modifying of nanostructured cBN with aluminum increases the strength of the additives retention in the aluminum matrix. At the same time the increase in the concentration of BN additives from 1.5 to 5 wt.% as well as the increase in the treatment temperature at a fixed pressure promotes the increase in the microhardness of the material by a factor of 1.5 to 2 as compared with the base aluminum alloy without the addition of a modifier. An increase in the cBN concentration to 5 % by weight results in an increase in the fraction of smaller particle conglomerates (1–5 μm) in the material and in a decrease in the size of large inclusions to 10–20 μm. In this case, the distribution of BN particles in the aluminum matrix is more uniform in comparison with a material with a cBN content of 1.5 wt.%. In the material with the growth of temperature up to 1000 °С, cBN in aggregates is recrystallized with the formation of single-crystal (polycrystalline) particles with the size of 1–10 μm with faceting specific for cBN micron particles.

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Effect of pressure treatment on the cathodoluminescence spectra of sphalerite boron nitride

Journal of Applied Spectroscopy ◽

10.1007/bf00662789 ◽

1988 ◽

Vol 49 (3) ◽

pp. 947-951 ◽

Cited By ~ 1

Author(s):

V. B. Shipilo ◽

E. M. Shishonok ◽

A. M. Zaitsev ◽

A. A. Mel'nikov ◽

A. I. Olekhnovich

Keyword(s):

Boron Nitride ◽

Pressure Treatment ◽

Effect Of Pressure

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Structural Evolution in Mechanically Alloyed Fe-Sn

Mössbauer Spectroscopy in Materials Science ◽

10.1007/978-94-011-4548-0_15 ◽

1999 ◽

pp. 151-160 ◽

Cited By ~ 4

Author(s):

G. A. Dorofeev ◽

G. N. Konygin ◽

E. P. Yelsukov ◽

I. V. Povstugar ◽

A. N. Streletskii ◽

...

Keyword(s):

Structural Evolution ◽

Mechanically Alloyed

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A Nano-Silver Inkjet Conductive Ink with Excellent Adhesion

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.262.501 ◽

2012 ◽

Vol 262 ◽

pp. 501-504 ◽

Cited By ~ 5

Author(s):

Jun Ran ◽

Li Xin Mo ◽

Wen Bo Li ◽

Wei Wei Li ◽

Xin Ming Fan ◽

...

Keyword(s):

Structural Evolution ◽

Heat Treating ◽

Treatment Temperature ◽

Protective Agent ◽

Conductive Ink ◽

Post Heat Treatment ◽

Nano Silver ◽

Conductive Materials ◽

Excellent Adhesion ◽

Printed Patterns

In this paper，the preparation of a solvent based nano-silver inkjet conductive ink with excellent adhesion was investigated and applied. Nano-silver particles, with dodecylamine (DDA) as the protective agent, were prepared and the effect of protective agent on the post heat-treatment of nano- silver ﬁlms was investigated. Results of electrical resistance, micro-structural evolution and thermal analysis showed that the Ag/DDA ﬁlms require a relatively low treatment temperature to convert into conductive materials. Then the conductive ink was prepared with well dispersed Ag/DDA nanoparticles and the ink was printed patterns on PET、PI ﬁlms through EPSON ME 33 inkjet printer , the patterns showed a sheet resistance is 182.3mΩ/□ and the adhesion reached to 5B after heat-treating at 120°C for 60min .

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