High-temperature magnetic coercivity of CNTs filled with multi-phase Fe-based nanoparticles

Dual multi-phase intermetallic alloy, which is composed of Ni3Al(L12) and Ni solid solution (A1) phases at high temperature annealing and is additionally refined by a eutectoid reaction at low temperature annealing, according to which the Al phase is transformed into the Ni3Al(L12)+Ni3V(D022) phases, was prepared. High-temperature tension and creep test were conducted using single crystalline materials. The alloy with such a novel microstructure showed extremely high yield and tensile stresses with good temperature retention. The creep test conducted at high temperature showed extremely low creep rate and creep rupture time when compared with advanced Ni-based superalloys. The results obtained are promising for the development of a new-type of high-temperature structural materials.

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High Temperature Mechanical Behavior of a Mo-Si-B Solid Solution Alloy

MRS Proceedings ◽

10.1557/proc-980-0980-ii06-03 ◽

2006 ◽

Vol 980 ◽

Author(s):

Padam Jain ◽

K. S. Kumar

Keyword(s):

Solid Solution ◽

High Temperature ◽

Mechanical Response ◽

Tensile Tests ◽

Solid Solution Alloy ◽

Solid Solution Phase ◽

Nominal Strain Rate ◽

Three Phase ◽

The Matrix ◽

Multi Phase

AbstractMulti phase alloys at the Mo-rich end of the Mo-Si-B system have drawn recent attention because of their high temperature performance capabilities. Previous studies on two- and three-phase alloys have confirmed the central role of the Mo-rich solid solution phase in affecting creep resistance and low-temperature toughness in these multiphase alloys. Thus, it is important to understand the intrinsic mechanical response of the matrix solid solution. In this study, compression and tensile tests were conducted over a nominal strain rate regime spanning 10-4 s-1 to 10-7 s-1 and temperature ranging from 1000°C to 1300°C in vacuum on a Mo-Si-B solid solution alloy (Mo-3Si-1.3B in at.%) that contained a low fraction (~5 %) of the T2 phase. The microstructure of the deformed specimens was examined to elucidate the underlying deformation mechanisms.

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Solidification Behavior of Lined Al2O3-ZrO2 Multiphase Ceramics in SHS Composite Pipes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.905.109 ◽

2014 ◽

Vol 905 ◽

pp. 109-112

Author(s):

Gui Bo Yu ◽

Feng He Tao ◽

Shu Hai Wang ◽

Li Jun Cao ◽

Qiao Ma

Keyword(s):

High Temperature ◽

Combustion Synthesis ◽

Solidification Behavior ◽

Boundary Area ◽

Multi Phase ◽

Composite Pipes ◽

Multiphase Ceramics

Hypoeutectic and hypereutectic Al2O3+ZrO2 multiphase ceramic-lined composite pipes were produced by using the gravitational separation self-propagate high-temperature (SHS) process. The microstructure of the ceramics was observed by means of SEM and EPMA. The multi-phase ceramics base consists of lamellar or rod-like eutecticum of ZrO2with Al2O3, and Al2O3dendrite is distributed between (Al2O3+ZrO2) eutecticum and the ZrO2is distributed on boundary area between (Al2O3+ZrO2) eutecticum in appearance of band and particle alone in the hypoeutectic multi-phase ceramics, and ZrO2is distributed between (Al2O3+ZrO2) eutecticum in appearance of snowflake-like or fishbone-like in hypereutectic multi-phase ceramics. On the basis of combustion synthesis, material thermodynamics, metallurgy dynamics and ceramics materials theory, the formation of microstructure mechanism have been systematically investigated.

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Microstructures and Mechanical Properties in Ni3Si-Ni3Ti-Ni3Nb-Based Multi-Intermetallic Alloys

MRS Proceedings ◽

10.1557/proc-842-s2.5 ◽

2004 ◽

Vol 842 ◽

Author(s):

T. Takasugi ◽

K. Ohira ◽

Y. Kaneno

Keyword(s):

High Temperature ◽

Tensile Stress ◽

Oxidation Resistance ◽

Tensile Elongation ◽

Intermetallic Alloy ◽

Boron Addition ◽

Intermetallic Alloys ◽

Phase Intermetallic ◽

Si Content ◽

Multi Phase

ABSTRACTMicrostructure, high-temperature tensile deformation and oxidation property of Ni3Si-Ni3Ti-Ni3Nb multi-phase intermetallic alloys with a microstructure consisting of L12, D024 and D0a phases were investigated. The tensile stress as well as the tensile elongation of these multi-phase alloys increased with increasing Si content, i.e. the volume fraction of L12 phase in the wide range of test temperatures. 50-ppm boron addition to these multi-phase intermetallic alloys resulted in increased tensile stress and tensile elongation. The multi-phase intermetallic alloy with a high Si content had good oxidation resistance, and also the boron addition to this alloy resulted in enhanced oxidation resistance. From an overall evaluation of the properties examined, it was shown that the multi-phase intermetallic alloy, which has a high Si content and is composed of L12 matrix dispersed by D024 and D0a phases, had the most favorable properties as high-temperature mechanical and chemical materials.

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Microstructure and Mechanical Properties of Dual Two-Phase Intermetallic Alloys Composed of GCP Ni3Al and Ni3V Phases containing Nb

MRS Proceedings ◽

10.1557/proc-980-0980-ii05-27 ◽

2006 ◽

Vol 980 ◽

Author(s):

Wataru Soga ◽

Yasuyuki Kaneno ◽

Takayuki Takasugi

Keyword(s):

High Temperature ◽

Creep Test ◽

Alloy System ◽

High Yield ◽

Intermetallic Alloys ◽

Two Phase ◽

Electron Microscopies ◽

Compression Creep ◽

Phase Intermetallic ◽

Multi Phase

AbstractDual multi-phase intermetallic alloys composed of Ni3X (X: Al and V) containing Nb were developed, on the basis of the Ni3Al-Ni3Nb-Ni3V pseudo-ternary alloy system. The dual multi-phase intermetallic alloys were characterized by scanning electron and transmission electron microscopies. High-temperature compression and tension tests, and compression creep test were conducted. It was found that the dual multi-phase intermetallic alloys show high yield and tensile strength with good temperature retention, accompanied with reasonable tensile ductility. The compression creep test conducted at high temperature showed lower creep rate in the dual multi-phase intermetallic alloys than in conventional Ni-base superalloys. The obtained results are superior to the dual multi-phase intermetallic alloys containing Ti.

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Hierarchical multi-phase microstructural architecture for exceptional strength-ductility combination in a complex concentrated alloy via high-temperature severe plastic deformation

Scripta Materialia ◽

10.1016/j.scriptamat.2018.10.033 ◽

2019 ◽

Vol 162 ◽

pp. 38-43 ◽

Cited By ~ 9

Author(s):

Mageshwari Komarasamy ◽

Tianhao Wang ◽

Kaimiao Liu ◽

Luis Reza-Nieto ◽

Rajiv S. Mishra

Keyword(s):

Plastic Deformation ◽

High Temperature ◽

Severe Plastic Deformation ◽

Multi Phase

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Erbium boride composites with high ZT values at 800 K

MRS Proceedings ◽

10.1557/opl.2013.400 ◽

2013 ◽

Vol 1490 ◽

pp. 41-44

Author(s):

Frederick C. Stober ◽

Barbara R. Albert

Keyword(s):

High Temperature ◽

Energy Conversion ◽

Single Phase ◽

Rietveld Analysis ◽

Molar Ratio ◽

Refractory Materials ◽

Solid Reaction ◽

Seebeck Coefficients ◽

Electrical Conductivities ◽

Multi Phase

ABSTRACTSingle phase erbium borides ErB2, ErB4, and ErB12 show Seebeck coefficients and power factors with absolute values that are significantly lower than those of a stable Er-B multi phase composite obtained through high temperature solid-solid reaction from the elements (molar ratio Er:B = 1:6). According to quantitative Rietveld analysis the composite consists of erbium diboride (1 %), tetraboride (83 %), and dodecaboride (16 %), and the measurement of the electrical conductivities, Seebeck coefficients, and thermal conductivities leads to ZT values as high as 0.53 at 830 K. Such refractory materials can be used for energy conversion in a range of high temperatures that are otherwise difficult to address.

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