Methods to improve mechanical characteristics of ceramics on the basis of zirconium and hafnium diborides (Review)

This paper describes the main methods for improving the mechanical properties of ceramic materials based on zirconium and hafnium diborides, such as strength and crack resistance. Particular attention is paid to the influence of the sintering method, as well as additives introduced into the powder composition, in particular hard fibers, second-phase powder particles and “whiskers”, on the mechanical characteristics of the ceramics. On the basis of the analysis of literature data, it is shown that the spark plasma sintering (SPS) method allows to obtain ceramic samples with increased mechanical characteristics due to their high density and low defects. The addition of silicon carbide filamentous crystals or fibers to the ceramics can increase the crack resistance of the sintered material up to 6.0–8.5 MPa×m1/2. These conclusions can be useful in the development of ultra-high-temperature ceramic materials.

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Fabrication and Mechanical Characteristics of Bulk Nickel/Carbon Nanotube Nanocomposites via the Electrical Explosion of Wire in Liquid and Spark Plasma Sintering Method

Journal of Korean Powder Metallurgy Institute ◽

10.4150/kpmi.2016.23.3.213 ◽

2016 ◽

Vol 23 (3) ◽

pp. 213-220 ◽

Cited By ~ 2

Author(s):

Thuyet-Nguyen Minh ◽

◽

Hai-Nguyen Hong ◽

Won Joo Kim ◽

Ho Yoon Kim ◽

...

Keyword(s):

Carbon Nanotube ◽

Spark Plasma Sintering ◽

Mechanical Characteristics ◽

Electrical Explosion ◽

Plasma Sintering ◽

Spark Plasma ◽

Sintering Method

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Synthesis of Bulk Quasicrystals by Spark Plasma Sintering

MRS Proceedings ◽

10.1557/proc-643-k2.1 ◽

2000 ◽

Vol 643 ◽

Cited By ~ 1

Author(s):

E. Fleury ◽

J.H. Lee ◽

S.H. Kim ◽

G.S. Song ◽

J.S. Kim ◽

...

Keyword(s):

Fracture Toughness ◽

Spark Plasma Sintering ◽

Vickers Microhardness ◽

Secondary Phases ◽

Hot Press ◽

Plasma Sintering ◽

Short Period ◽

Spark Plasma ◽

Powder Particles ◽

Sintering Method

AbstractSpark plasma sintering method was applied to Al-Cu-Fe and Al-Si-Cu-Fe gas-atomized powders to prepare almost pore-free cylindrical specimens with icosahedral and 1/1 cubic approximant phases, respectively. This investigation has revealed that a high density could be obtained despite the short period and low temperature imposed during spark plasma sintering. In comparison to hot press technique, these conditions are favorable since they limit the formation of secondary phases and avoid exaggerated grain growth. The Vickers microhardness and fracture toughness of these two alloy systems were found to be larger than those obtained from cast and hot pressed samples, which could be attributed to a strong bonding between powder particles and the small-grained microstructure of the bulk SPS quasicrystalline specimens.

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Characterization and Production of Structurat Ceramics in the Systems Fe(1-X)O-Fe3O4 and MgO-MgFe2O4.

Microscopy and Microanalysis ◽

10.1017/s1431927600017372 ◽

1999 ◽

Vol 5 (S2) ◽

pp. 810-811

Author(s):

A. Huerta ◽

R. Ordoñez ◽

H.A. Calderon ◽

M. Umemoto ◽

K. Tsuchiya ◽

...

Keyword(s):

Ceramic Materials ◽

Grain Structure ◽

Second Phase ◽

Magnetic Recording Media ◽

Mechanically Alloyed ◽

Ceramic Oxides ◽

Plasma Sintering ◽

Structural Applications ◽

Spark Plasma ◽

Second Phases

Ceramic materials are widely studied for their high temperature structural applications. In many crystalline ceramics the range of solid solution decreases with temperature and thus precipitation of a second phase occurs. Thus, ceramics can be hardened by precipitation of second phases. However little is known regarding the effect of precipitation and nanocrystalline grain structure in the ductility of ceramic materials. On the other hand, oxide ceramics are under intense-investigation for their technological advantages in magnetization, dielectric response and chemical stability in such diverse uses as magnetic recording media, induction cores and microwave resonant circuits. This investigation has been undertaken to produce, characterize and measure the properties of ceramics that can be hardened by precipitation. The selected systems include Fe(1-x)O-Fe3 and MgO MgFe2O4. Mechanical milling is used to produce nanocrystalline ceramic oxides in the systems Fe(1-x)O-Fe3 and MgO-MgFe2O4 The mechanically alloyed powders are consolidated by means of spark plasma sintering (SPS) at temperatures ranging from 673 K to 1273 K and a pressure varying from 500 to 50 MPa in vacuum.

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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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EDM processing of sintered ceramic materials using the SPS method

Mechanik ◽

10.17814/mechanik.2018.3.39 ◽

2018 ◽

Vol 91 (3) ◽

pp. 240-243

Author(s):

Andrzej Nowakowski ◽

Tadeusz Krzywda ◽

Piotr Putyra

Keyword(s):

Electrical Conductivity ◽

Ceramic Composite ◽

Physical And Mechanical Properties ◽

Ceramic Materials ◽

Sintered Ceramic ◽

Electro Discharge Machining ◽

Plasma Sintering ◽

Spark Plasma ◽

Si3n4 Matrix ◽

Sintering Method

Presented are the analysis of physical and mechanical properties of the Al2O3, SiC and Si3N4 matrix ceramics with additives of good electrical conductivity phases and TiB2 matrix ceramics. The density, Young’s modulus, hardness HV1 and electrical conductivity of each material were investigated. Ceramic composite materials with the participation of the conductive phases have been produced using SPS (spark plasma sintering) method. Materials characterized by good electrical conductivity were shaped using EDM (electro discharge machining) method.

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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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