The Influence of Boron Additions in Cast Ti-47AL-2Cr-2Nb-0.8B

AbstractMorphology, fine structure, and chemistry of phases formed in cast Ti-47Al-2Cr-2Nb-0.8B due to boron addition were examined in detail. Boron acts an inoculant, refining and stabilizing the cast grain size. A curving ribbon-shaped phase was present throughout the material, related to the ordered phase Ti2AlCr. The ribbon phase had the B2 structure, with a0∼0.318nm. Many ribbons had a low degree of order, i. e. the material was a BCC mixture of Ti, Al, Nb, and Cr. Ribbon phase composition was variable, measured to be: Ti-(20–30)Al-(2–4)Nb-(5–16)Cr. TiB2 was present in small amounts, always in intimate contact with the ribbon phase. A (100)ribbon ‖ {1100}TiB2, (011)ribbon ‖ {1122}TiB2 orientation relationship was observed. It is proposed that the ribbon phase is a remnant of the high-temperature titanium aluminide β-phase, stabilized by dissolved boron.

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The Effect of Stoichiometry and Degree of Order on Mechanical Properties of Ni3Fe Intermetallics

Materials Science Forum ◽

10.4028/www.scientific.net/msf.747-748.19 ◽

2013 ◽

Vol 747-748 ◽

pp. 19-24 ◽

Cited By ~ 2

Author(s):

Ye Xin Chen ◽

Hai Yan Qian ◽

Tao Chen

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Tensile Strength ◽

Phase Composition ◽

Point Defects ◽

Deformation Behavior ◽

Disordered Alloys ◽

Fe Intermetallics ◽

Degree Of Order ◽

Disordered Alloy

The effects of Fe stoichiometry and degree of order on mechanical properties of intermetallics Ni3Fe were investigated. The experimental results showed that the phase composition and the grain size of Ni3Fe alloy was independent on Fe stoichiometry. The Ni3Fe alloy with the normal stoichiometry had the lowest elongation in the ordered and disordered alloys. The tensile strength of Ni3Fe alloy depended on Fe stoichiometry of alloy. The effect of Fe stoichiometry on the mechanical properties of the ordered alloy was larger than that of disordered alloy. There were more point defects in lattice when the alloy stoichiometry deviating from the normal stoichiometry in the Ni3Fe alloy. The changes of the concentration of the point defects and degree of order altered the deformation behavior of the Ni3Fe alloy.

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High thermal conductivity of pure dense SiC ceramics prepared via HTPVT

Functional Materials Letters ◽

10.1142/s1793604719500322 ◽

2019 ◽

Vol 12 (03) ◽

pp. 1950032 ◽

Cited By ~ 2

Author(s):

Yuchen Deng ◽

Yaming Zhang ◽

Nanlong Zhang ◽

Qiang Zhi ◽

Bo Wang ◽

...

Keyword(s):

Thermal Conductivity ◽

Silicon Carbide ◽

Grain Size ◽

Phase Composition ◽

Room Temperature ◽

Vapor Transport ◽

Physical Vapor Transport ◽

Growth Substrate ◽

Sic Ceramics ◽

Evolution Of Microstructure

Pure dense silicon carbide (SiC) ceramics were obtained via the high-temperature physical vapor transport (HTPVT) method using graphite paper as the growth substrate. The phase composition, the evolution of microstructure, the thermal diffusivity and thermal conductivity at RT to 200∘C were investigated. The obtained samples had a relative density of higher than 98.7% and a large grain size of 1[Formula: see text]mm, the samples also had a room-temperature thermal conductivity of [Formula: see text] and with the temperature increased to 200∘C, the thermal conductivity still maintained at [Formula: see text].

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Effect of Grain Size on Deformation Twinning Behavior of Ti6Al4V Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.830-831.337 ◽

2015 ◽

Vol 830-831 ◽

pp. 337-340

Author(s):

Ashish Kumar Saxena ◽

Manikanta Anupoju ◽

Asim Tewari ◽

Prita Pant

Keyword(s):

Plastic Deformation ◽

Grain Size ◽

Strain Rate ◽

Deformation Behavior ◽

Deformation Behaviour ◽

Air Cooling ◽

Specific Strength ◽

Aerospace Applications ◽

Β Phase ◽

Plastic Deformation Behavior

An understanding of the plastic deformation behavior of Ti6Al4V (Ti64) is of great interest because it is used in aerospace applications due to its high specific strength. In addition, Ti alloys have limited slip systems due to hexagonal crystal structure; hence twinning plays an important role in plastic deformation. The present work focuses upon the grain size effect on plastic deformation behaviour of Ti64. Various microstructures with different grain size were developed via annealing of Ti64 alloy in α-β phase regime (825°C and 850°C) for 4 hours followed by air cooling. The deformation behavior of these samples was investigated at various deformation temperature and strain rate conditions. Detailed microstructure studies showed that (i) smaller grains undergoes twinning only at low temperature and high strain rate, (ii) large grain samples undergo twinning at all temperatures & strain rates, though the extent of twinning varied.

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Deuterium and phosphorus-31 nuclear magnetic resonance of cholesteryl palmitate in dipalmitoylphosphatidylcholine model membranes

Canadian Journal of Chemistry ◽

10.1139/v80-392 ◽

1980 ◽

Vol 58 (23) ◽

pp. 2433-2441 ◽

Cited By ~ 8

Author(s):

Robert J. Cushley ◽

Heiner Gorrissen ◽

Stephen R. Wassall

Keyword(s):

Nuclear Magnetic Resonance ◽

Magnetic Resonance ◽

Liquid Crystalline ◽

Acyl Chain ◽

Relaxation Times ◽

Average Diameter ◽

Low Degree ◽

Cholesteryl Palmitate ◽

Degree Of Order ◽

Ester Chain

Cholesteryl palmitate (CP) bas been incorporated into vesicles of dipalmitoylphosphatidylcholine and dipalmitoylphosphatidylcholine/20 mol% cholesterol, in amounts up to 5 mol%. By means of 31P lanthanide induced shifts the average diameter of these vesicles was calculated to be ~270 Å.The 2H spectral linewidths of selectively deuterated CP incorporated into liquid crystalline dipalmitoylphosphatidylcholine vesicles are ≤ 150 Hz, implying a low degree of order for the ester acyl chain. Addition of 20 mol% cholesterol to the vesicles increases the linewidths which, nevertheless, remain ≤ 185 Hz. The corresponding 2H longitudinal relaxation times (≤ 450 ms) indicate that the fast segmental motions of the ester chain are slower than for the phospholipid chains.

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The Effect of Porosity and Grain Size on the Phase Composition and Mechanical Properties of Zirconium-Dioxide-Based Ceramic

Technical Physics Letters ◽

10.1134/s1063785018080096 ◽

2018 ◽

Vol 44 (8) ◽

pp. 663-666 ◽

Cited By ~ 12

Author(s):

N. L. Savchenko ◽

T. Yu. Sablina ◽

I. N. Sevost’yanova ◽

A. G. Burlachenko ◽

S. P. Buyakova ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Phase Composition ◽

Zirconium Dioxide

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Correction: Liss, K.-D., et al. Hydrostatic Compression Behavior and High-Pressure Stabilized β-Phase in γ-Based Titanium Aluminide Intermetallics. Metals 2016, 6, 165

Metals ◽

10.3390/met7090353 ◽

2017 ◽

Vol 7 (9) ◽

pp. 353

Author(s):

Klaus-Dieter Liss ◽

Ken-Ichi Funakoshi ◽

Rian Dippenaar ◽

Yuji Higo ◽

Ayumi Shiro ◽

...

Keyword(s):

High Pressure ◽

Titanium Aluminide ◽

Hydrostatic Compression ◽

Compression Behavior ◽

Β Phase

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Morphology and Mechanical Properties of 3Y-TZP Nanofiber Mats

Nanomaterials ◽

10.3390/nano10112097 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2097

Author(s):

Alexander I. Tyurin ◽

Vyacheslav V. Rodaev ◽

Svetlana S. Razlivalova ◽

Viktor V. Korenkov ◽

Andrey O. Zhigachev ◽

...

Keyword(s):

Mechanical Properties ◽

Grain Size ◽

Phase Composition ◽

Calcination Temperature ◽

Tetragonal Zirconia ◽

Calcination Temperatures ◽

Nanoindentation Testing ◽

Average Grain Size ◽

Nanofiber Mats ◽

Morphology And Mechanical Properties

The mats of yttria-stabilized tetragonal zirconia nanofibers were prepared using electrospinning. The effect of calcination temperature in the range of 600–1200 °C on their microstructure, phase composition and mechanical properties was investigated. Phase composition of the nanofibers did not change in all ranges of the calcination temperatures, while the average grain size increased from 8 to 39 nm. Nanoindentation testing of the mats showed a decrease in the hysteresis loop energy in samples with higher calcination temperature. Hardness and the elastic modulus measured with the indentation technique were the highest for the mats calcined at 900 °C.

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