Nonstoichiometric Composition and Densification of CaRuO3 by SPS

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.352.251 ◽

2007 ◽

Vol 352 ◽

pp. 251-254 ◽

Cited By ~ 1

Author(s):

Nittaya Keawprak ◽

Rong Tu ◽

Takashi Goto

Keyword(s):

Spark Plasma Sintering ◽

Single Phase ◽

Lattice Parameters ◽

Second Phase ◽

Nonstoichiometric Composition ◽

Plasma Sintering ◽

Spark Plasma

Calcium ruthenates were prepared in different ratios of Ru to Ca (RRu/Ca = 0.5～1.4) by spark plasma sintering. CaRuO3 in a single phase was obtained at RRu/Ca = 1.0. At RRu/Ca < 1.0, a mixture of CaRuO3 and CaO was obtained, whereas CaRuO3 with second phase of RuO2 was obtained at RRu/Ca > 1.0. The density at RRu/Ca < 1.0 were 80-85% and slightly increased with increasing RRu/Ca. The density significantly increased up to 95% with increasing RRu/Ca from 1.1 to 1.4, suggesting that the second phase of RuO2 was effective to densify CaRuO3. The density of CaRuO3 in a single phase was 82% at most. The lattice parameters of CaRuO3 decreased with increasing RRu/Ca from 0.7 to 1.0, showing a nonstoichiometric range of Ca1+δRuO3+δ.

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Effect of Nano-Y2O3 Addition on Microstructure and Tensile Properties of High-Nb TiAl Alloy Prepared by Spark Plasma Sintering

Metals ◽

10.3390/met11071048 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1048

Author(s):

Yingchao Guo ◽

Yongfeng Liang ◽

Junpin Lin ◽

Fei Yang

Keyword(s):

Tensile Strength ◽

Spark Plasma Sintering ◽

Tial Alloy ◽

Second Phase ◽

Fine Grain ◽

Fine Grain Strengthening ◽

Plasma Sintering ◽

Spark Plasma ◽

Y2o3 Addition ◽

Powder Metallurgy Route

Nano-Y2O3 reinforced Ti-47.7Al-7.1Nb-(V, Cr) alloy was fabricated by a powder metallurgy route using spark plasma sintering (SPS), and the influence of nano-Y2O3 contents on the microstructure and mechanical properties were investigated systematically. The results revealed that the ultimate tensile strength and elongation of the alloy were 570 ± 28 MPa and 1.7 ± 0.6% at 800 °C, 460 ± 23 MPa and 6.1 ± 0.4% at 900 °C with no nano-Y2O3, 662 ± 24 MPa and 5.5 ± 0.5% at 800 °C, and 466 ± 25 MPa and 16.5 ± 0.8% at 900 °C with 0.05 at% nano-Y2O3 addition, respectively. Due to the fine-grain strengthening and the second-phase strengthening, both tensile strength and elongation of the high-Nb TiAl alloy were enhanced with the addition of nano-Y2O3.

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Thermoelectric properties of Cu3SbSe3 with intrinsically ultralow lattice thermal conductivity

Journal of Materials Chemistry A ◽

10.1039/c4ta02590c ◽

2014 ◽

Vol 2 (38) ◽

pp. 15829-15835 ◽

Cited By ~ 34

Author(s):

Kriti Tyagi ◽

Bhasker Gahtori ◽

Sivaiah Bathula ◽

A. K. Srivastava ◽

A. K. Shukla ◽

...

Keyword(s):

Thermal Conductivity ◽

Solid State ◽

Spark Plasma Sintering ◽

Thermoelectric Properties ◽

Solid State Reaction ◽

Electrical Transport ◽

Single Phase ◽

Lattice Thermal Conductivity ◽

Plasma Sintering ◽

Spark Plasma

Intrinsically ultra-low thermal conductivity and electrical transport in single-phase Cu2SbSe3 synthesized employing a solid state reaction and spark plasma sintering.

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Transparent mullite ceramic from single-phase gel by Spark Plasma Sintering

Journal of the European Ceramic Society ◽

10.1016/j.jeurceramsoc.2009.04.012 ◽

2009 ◽

Vol 29 (13) ◽

pp. 2705-2711 ◽

Cited By ~ 32

Author(s):

Guimin Zhang ◽

Yucheng Wang ◽

Zhengyi Fu ◽

Hao Wang ◽

Weiming Wang ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Single Phase ◽

Mullite Ceramic ◽

Plasma Sintering ◽

Spark Plasma

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Development of calcium stabilized nitrogen rich α-sialon ceramics along the Si3N4:1/2Ca3N2:3AlN line using spark plasma sintering

Journal of Advanced Ceramics ◽

10.1007/s40145-020-0400-y ◽

2020 ◽

Vol 9 (5) ◽

pp. 606-616

Author(s):

B. A. Ahmed ◽

T. Laoui ◽

A. S. Hakeem

Keyword(s):

Spark Plasma Sintering ◽

Single Phase ◽

Sintering Temperature ◽

Compositional Analysis ◽

Physical And Mechanical Properties ◽

Alkaline Metal ◽

Maximum Hardness ◽

Plasma Sintering ◽

Alkaline Metal Cation ◽

Spark Plasma

Abstract Calcium stabilized nitrogen rich sialon ceramics having a general formula of CaxSi12-2xAl2xN16 with x value (x is the solubility of cation Ca in α-sialon structure) in the range of 0.2–2.2 for compositions lying along the Si3N4:1/2Ca3N2:3AlN line were synthesized using nano/submicron size starting powder precursors and spark plasma sintering (SPS) technique. The development of calcium stabilized nitrogen rich sialon ceramics at a significantly low sintering temperature of 1500 °C (typically reported a temperature of 1700 °C or greater) remains to be the highlight of the present study. The SPS processed sialons were characterized for their microstructure, phase and compositional analysis, and physical and mechanical properties. Furthermore, a correlation was developed between the lattice parameters and the content (x) of the alkaline metal cation in the α-sialon phase. Well-densified single-phase nitrogen rich α-sialon ceramics were achieved in the range of 0.53(3) ⩽ x ⩽ 1.27(3). A nitrogen rich α-sialon sample possessing a maximum hardness of 22.4 GPa and fracture toughness of 6.1 MPa·m1/2 was developed.

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Development of calcium stabilized nitrogen rich alpha-sialon ceramics along the Si3N4:1/2Ca3N2:3AlN line using spark plasma sintering

10.21203/rs.3.rs-21600/v2 ◽

2020 ◽

Author(s):

Bilal Anjum Ahmed ◽

Abbas Saeed Hakeem ◽

Tahar Laoui

Keyword(s):

Spark Plasma Sintering ◽

Single Phase ◽

Sintering Temperature ◽

Compositional Analysis ◽

Physical And Mechanical Properties ◽

Alkaline Metal ◽

Maximum Hardness ◽

Plasma Sintering ◽

Alkaline Metal Cation ◽

Spark Plasma

Abstract Calcium stabilized nitrogen rich sialon ceramics having a general formula of CaxSi12-2xAl2xN16 with x value in the range of 0.2-2.2 for compositions lying along the Si3N4:1/2Ca3N2:3AlN line were synthesized using nano/submicron size starting powder precursors and spark plasma sintering (SPS) technique. The development of calcium stabilized nitrogen rich sialon ceramics at a significantly low sintering temperature of 1500°C (typically reported a temperature of 1700°C or greater) remains to be the highlight of the present study. The SPS processed sialons were characterized for their microstructure, phase and compositional analysis, physical and mechanical properties. Furthermore, a correlation was developed between the lattice parameters and the content (x) of the alkaline metal cation in the alpha-sialon phase. Well densified single-phase nitrogen rich alpha-sialon ceramics were achieved in the range of 0.53(3) ≤ x ≤ 1.27(3). A nitrogen rich alpha-sialon sample possessing a maximum hardness of 22.4 GPa and fracture toughness of 6.1 MPa.m1/2 was developed.

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Structural transformations of a gas-atomized Al62.5Cu25Fe12.5 alloy during detonation spraying, spark plasma sintering and hot pressing

Science of Sintering ◽

10.2298/sos2103379b ◽

2021 ◽

Vol 53 (3) ◽

pp. 379-386

Author(s):

Igor Batraev ◽

Witor Wolf ◽

Boris Bokhonov ◽

Arina Ukhina ◽

Ivanna Kuchumova ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Hot Pressing ◽

Single Phase ◽

Complex Structure ◽

Icosahedral Phase ◽

Structural Transformations ◽

Detonation Spraying ◽

Complete Melting ◽

Plasma Sintering ◽

Spark Plasma

In this work, we traced structural transformations of an Al62.5Cu25Fe12.5 alloy, in which a quasicrystalline icosahedral phase (i-phase) can be formed, upon spraying onto a substrate and consolidation from the powder into the bulk state. The Al62.5Cu25Fe12.5 powder was obtained by gas atomization and consisted of i-phase and ?-phase AlCu(Fe). The powder was detonation sprayed (DS) and consolidated by spark plasma sintering (SPS)/hot pressing (HP). During DS, the particles experienced partial or complete melting and rapid solidification, which resulted in the formation of coatings of a complex structure. The composite regions containing i-phase were inherited from the powder alloy. The fraction of the material that experienced melting solidified as ?-phase AlFe(Cu) in the coating. It was suggested that the difficulty of obtaining i-phase upon post-spray annealing is related to aluminum depletion of the alloy during DS. During SPS and HP, the elemental composition of the alloy was preserved, while the exposure to an elevated temperature led to phase homogenization. SPS and HP conducted at 700?C resulted in full densification and the formation of a single-phase quasicrystalline alloy. The sintered single-phase alloy showed a higher microhardness in comparison with the DS coatings.

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Fabrication Processes and Properties of Highly Pure MgAlON Materials

Materials Science Forum ◽

10.4028/www.scientific.net/msf.561-565.543 ◽

2007 ◽

Vol 561-565 ◽

pp. 543-546 ◽

Cited By ~ 1

Author(s):

Qing Huang ◽

Yong Huang ◽

Chang An Wang ◽

Hou Xing Zhang

Keyword(s):

Spark Plasma Sintering ◽

Open Porosity ◽

Single Phase ◽

Bending Strength ◽

Sintering Temperature ◽

Hot Press ◽

Plasma Sintering ◽

Short Period ◽

Spark Plasma ◽

Hot Press Sintering

In this paper, the MgAlON ceramic was fabricated by Spark Plasma Sintering (SPS) and hot press sintering respectively. The results showed that highly pure and single-phase MgAlON could be fabricated at lower sintering temperature in a short period through SPS process, compared with the conventional Hot Press sintering (HP) process. The bending strength of MgAlON specimens prepared by SPS process was higher than 500MPa while bending strength of HP specimens was much lower. The open porosity was almost eliminated in SPS MgAlON specimens. Spark Plasma Sintered MgAlON had a single phase of MgAlON while Hot Press Sintered MgAlON had major MgAlON and minor AlN and Al2O3.

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Bimodal Microstructure in an AlZrTi Alloy Prepared by Mechanical Milling and Spark Plasma Sintering

Materials ◽

10.3390/ma13173756 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3756

Author(s):

Orsolya Molnárová ◽

Jan Duchoň ◽

Esther de Prado ◽

Štefan Csáki ◽

Filip Průša ◽

...

Keyword(s):

Spark Plasma Sintering ◽

Mechanical Milling ◽

Milled Powder ◽

Sintered Sample ◽

Second Phase ◽

Bimodal Microstructure ◽

Plasma Sintering ◽

Second Phase Particles ◽

Spark Plasma ◽

Powder Particles

The aim of this study was to prepare a low porosity bulk sample with a fine-grained structure from an AlZrTi alloy. Nanostructured powder particles were prepared by mechanical milling of gas atomized powder. The mechanically milled powder was consolidated using spark plasma sintering technology at 475 °C for 6 min using a pressure of 100 MPa. Sintering led to a low porosity sintered sample with a bimodal microstructure. The sintered sample was revealed to be composed of non-recrystallized grains with an approximate size of about 100 nm encompassed by distinct clusters of coarser, micrometer-sized grains. Whereas the larger grains were found to be lean on second phase particles, a high density of second phase particles was found in the areas of fine grains. The microhardness of the milled powder particles was established to be 163 ± 15 HV0.01, which decreased to a slightly lower value of 137 ± 25 HV0.01 after sintering.

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