Production of UHTC Complex Shapes and Architectures

In spite of the difficult sinterability of Zr and Hf borides and carbides, recent results highlight that these ceramics can be produced with full density, fine microstructure, and controlled mechanical and thermal properties, through different procedures: pressureless sintering and hot pressing with proper sintering aids, reactive synthesis/sintering procedures starting from precursors, and field assisted technologies like spark plasma sintering. More recently, the use of near net shaping techniques and the development of UHTC porous components open the way to further and innovative applications, where the performances, fixed the material, are linked to 2D or 3D architectures and the high ratio of specific surface area to volume of the component and to the features of the porosity itself. Structural lightweight parts, insulator panels, filters, radiant burners, and solar absorbers are some of the possible applications.

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Ultra-Fine Grained Ti-15Mo Alloy Prepared by Powder Metallurgy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.1276 ◽

2018 ◽

Vol 941 ◽

pp. 1276-1281

Author(s):

Anna Terynková ◽

Jiří Kozlík ◽

Kristína Bartha ◽

Tomáš Chráska ◽

Josef Stráský

Keyword(s):

Powder Metallurgy ◽

Bulk Material ◽

Alpha Phase ◽

Full Density ◽

Fine Grained ◽

Cryogenic Milling ◽

Aircraft Manufacturing ◽

Plasma Sintering ◽

Beta Matrix ◽

Spark Plasma

Ti-15Mo alloy belongs to metastable β-Ti alloys that are currently used in aircraft manufacturing and Ti15Mo alloy is a perspective candidate for the use in medicine thanks to its biotolerant composition. In this study, Ti15Mo alloy was prepared by advanced techniques of powder metallurgy. The powder of gas atomized Ti-15Mo alloy was subjected to cryogenic milling to achieve ultra-fine grained microstructure within the powder particles. Powder was subsequently compacted using spark plasma sintering (SPS). The effect of cryogenic milling on the microstructure and phase composition of final bulk material after SPS was studied by scanning electron microscopy. Sintering at 750°C was not sufficient for achieving full density in gas atomized powder, while milled material could be successfully sintered at this temperature. Alpha phase particles precipitated during sintering and their size, as well as the size of beta matrix grains, was strongly affected by the sintering temperature.

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Physical, mechanical properties and wear resistance of iron-base matrix materials for sintered diamond tools fabricated by HP and SPS

Mechanik ◽

10.17814/mechanik.2018.10.140 ◽

2018 ◽

Vol 91 (10) ◽

pp. 846-849

Author(s):

Elżbieta Bączek

Keyword(s):

Mechanical Properties ◽

Wear Resistance ◽

Metal Matrix ◽

Physical And Mechanical Properties ◽

Full Density ◽

Matrix Composites ◽

Plasma Sintering ◽

Base Matrix ◽

Spark Plasma ◽

Sintered Diamond

Metal matrix composites were prepared by hot pressing (HP) and spark plasma sintering (SPS) techniques. Ball-milled ironbase powders were consolidated to near full density by these methods at 900°C. The physical and mechanical properties of the resulting composites were investigated. The specimens were tested for resistance to both 3-body and 2-body abrasion. The composites obtained by HP method (at 900°C/35 MPa) had higher density, hardness and resistance to abrasion than those obtained by SPS method.

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Nearly full density Ni52.5Nb10Zr15Ti15Pt7.5 bulk metallic glass obtained by spark plasma sintering of gas atomized powders

Applied Physics Letters ◽

10.1063/1.2748102 ◽

2007 ◽

Vol 90 (24) ◽

pp. 241902 ◽

Cited By ~ 71

Author(s):

Guoqiang Xie ◽

Dmitri V. Louzguine-Luzgin ◽

Hisamichi Kimura ◽

Akihisa Inoue

Keyword(s):

Metallic Glass ◽

Bulk Metallic Glass ◽

Spark Plasma Sintering ◽

Full Density ◽

Plasma Sintering ◽

Spark Plasma

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Microstructure and Mechanical Properties of Spark-Plasma-Sintered SiC-TiC Composites

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.287.335 ◽

2005 ◽

Vol 287 ◽

pp. 335-339 ◽

Cited By ~ 7

Author(s):

Kyeong Sik Cho ◽

Kwang Soon Lee

Keyword(s):

Mechanical Properties ◽

Fracture Toughness ◽

Heating Rate ◽

Spark Plasma Sintering ◽

Sintering Temperature ◽

Applied Pressure ◽

Argon Atmosphere ◽

Full Density ◽

Plasma Sintering ◽

Spark Plasma

Rapid densification of the SiC-10, 20, 30, 40wt% TiC powder with Al, B and C additives was carried out by spark plasma sintering (SPS). In the present SPS process, the heating rate and applied pressure were kept at 100°C/min and at 40 MPa, while the sintering temperature varied from 1600-1800°C in an argon atmosphere. The full density of SiC-TiC composites was achieved at a temperature above 1800°C by spark plasma sintering. The 3C phase of SiC in the composites was transformed to 6H and 4H by increasing the process temperature and the TiC content. By tailoring the microstructure of the spark-plasma-sintered SiC-TiC composites, their toughness could be maintained without a notable reduction in strength. The strength of 720 MPa and the fracture toughness of 6.3 MPa·m1/2 were obtained in the SiC-40wt% TiC composite prepared at 1800°C for 20 min.

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Microstructure of Ti5Si3–TiC–Ti3SiC2 and Ti5Si3–TiC nanocomposites in situ synthesized by spark plasma sintering

Journal of Materials Research ◽

10.1557/jmr.2004.0365 ◽

2004 ◽

Vol 19 (10) ◽

pp. 3004-3008 ◽

Cited By ~ 31

Author(s):

Lianjun Wang ◽

Wan Jiang ◽

Lidong Chen ◽

Guangzhao Bai

Keyword(s):

Spark Plasma Sintering ◽

Microstructural Analysis ◽

Molar Ratio ◽

Reaction Products ◽

Plasma Sintering ◽

Transmission Electron ◽

Fine Microstructure ◽

Indentation Tests ◽

Spark Plasma ◽

Short Time

Nanostructured Ti5Si3–TiC–Ti3SiC2 and Ti5Si3–TiC composites were in situfabricated through the spark plasma sintering (SPS) technique using Ti and SiC powders as reactants. It was found that the composites could be prepared in arelatively short time (6 min at 1260 °C) above 98% theoretical density. The phase constituents and microstructures of the samples were analyzed by x-ray diffractionand observed by scanning electron microscopy. Transmission electron microscopywas used for detailed microstructural analysis. The results showed that the reaction products mainly consisted of Ti5Si3 and TiC phases or Ti5Si3, TiC and Ti3SiC2phases, depending on the molar ratio of reactants (Ti to SiC). The composites exhibited fine microstructure; TiC grain size was less than 200 nm. Fracturetoughness at room temperature was also measured by indentation tests.

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Corrosion-Resistance of Ni3Al Intermetallic Compounds Containing Cr Synthesized via Spark Plasma Sintering Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.581-582.1006 ◽

2012 ◽

Vol 581-582 ◽

pp. 1006-1009

Author(s):

Nian Liu ◽

Guo Dong Zhang ◽

Jin Lu Wu ◽

Fu Ju Zhang ◽

Jian Qiang Zhang

Keyword(s):

Corrosion Resistance ◽

Intermetallic Compounds ◽

Spark Plasma Sintering ◽

Chromium Content ◽

Full Density ◽

Sintering Process ◽

Anode Polarization ◽

Plasma Sintering ◽

Hardness Tests ◽

Spark Plasma

Ni3Al intermetallic compounds containing Cr was synthesized via Spark Plasma Sintering process. These Ni3Al intermetallic compounds containing Cr have a nearly full density after sintered at 1100 °C for 5 min under the pressure of 40MPa. Microstructure and hardness of these intermetallic compounds was studied through metallograph observation and micro hardness tests. Their formation and strengthening mechanisms were analyzed and discussed in detail. The influence of the chromium content on corrosion resistance of these intermetallic compounds was analyzed by anode polarization curves. Results show that the corrosion resistance of Ni3Al intermetallic compounds is upgraded significantly with increasing chromium content.

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Recent Advances on Bulk Tantalum Carbide Produced by Solvothermal Synthesis and Spark Plasma Sintering

MRS Proceedings ◽

10.1557/opl.2013.207 ◽

2012 ◽

Vol 1485 ◽

pp. 9-20 ◽

Cited By ~ 3

Author(s):

Braeden M. Clark ◽

James P. Kelly ◽

Olivia A. Graeve

Keyword(s):

Spark Plasma Sintering ◽

Tantalum Carbide ◽

Synthesis Process ◽

Full Density ◽

Sintering Behavior ◽

X Ray Diffraction ◽

Plasma Sintering ◽

Different Temperatures ◽

Spark Plasma ◽

Carbon Additions

ABSTRACTThe sintering of tantalum carbide nanopowders by spark plasma sintering (SPS) is investigated. The washing procedure for the powders is modified from previous work to eliminate excess lithium in the powders that is left over from the synthesis process. The sintering behavior of the nanopowders is investigated by X-ray diffraction and scanning electron microscopy by studying specimens that were sintered to different temperatures. To improve the homogeneity of the microstructure of the specimens, milling procedures were implemented. Vaporization during sintering is observed, and the usefulness of carbon additions and systematic decreases in temperature to curb this behavior was explored. Future experiments to achieve full density and to maintain a nanostructure of the specimens include sintering with higher pressures, lower temperatures, and longer dwell times. Additives for maintaining a nanostructure and developing suitable high-temperature properties are also discussed.

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Synthesis of Ceramic Reinforcements in Metallic Matrices during Spark Plasma Sintering: Consideration of Reactant/Matrix Mutual Chemistry

Ceramics ◽

10.3390/ceramics4040042 ◽

2021 ◽

Vol 4 (4) ◽

pp. 592-599

Author(s):

Dina V. Dudina ◽

Tomila M. Vidyuk ◽

Michail A. Korchagin

Keyword(s):

Spark Plasma Sintering ◽

Structural Evolution ◽

Ceramic Composites ◽

Ex Situ ◽

Full Density ◽

Powder Materials ◽

Plasma Sintering ◽

Processing Step ◽

Spark Plasma

Metal–ceramic composites are obtained via ex-situ or in-situ routes. The in-situ route implies the synthesis of reinforcement in the presence of a matrix and is often regarded as providing more flexibility to the microstructure design of composites than the ex-situ route. Spark plasma sintering (SPS) is an advanced sintering method that allows fast consolidation of various powder materials up to full or nearly full density. In reactive SPS, the synthesis and consolidation are combined in a single processing step, which corresponds to the in-situ route. In this article, we discuss the peculiarities of synthesis of ceramic reinforcements in metallic matrices during SPS with a particular consideration of reactant/matrix mutual chemistry. The formation of carbide reinforcements in Cu, Al, and Ni matrices is given attention with examples elaborated in the authors’ own research. Factors determining the suitability of reactive SPS for manufacturing of composites from a matrix/reactants system and features of the structural evolution of the reaction mixture during sintering are discussed.

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Examination of microstructure evolution and strengthening mechanisms in an aluminum-based hybrid composite prepared through the spark plasma sintering method

Metallurgical Research & Technology ◽

10.1051/metal/2020065 ◽

2020 ◽

Vol 117 (6) ◽

pp. 613

Author(s):

Mohammad Reza Rezaei ◽

Alireza Albooyeh ◽

Hassan Shiraghaei ◽

Misagh Shayestefar

Keyword(s):

Yield Strength ◽

Spark Plasma Sintering ◽

Hybrid Composite ◽

Full Density ◽

Interfacial Region ◽

Strengthening Mechanisms ◽

Consolidation Process ◽

Plasma Sintering ◽

Spark Plasma ◽

The Difference

A bulk hybrid composite to be potentially used as a foam precursor was produced in this study. TiH2 powder particles along with different concentrations of SiC were mixed with pure Al particles and consolidated through the spark plasma sintering (SPS) method. Bulk samples with nearly full density were successfully produced using the SPS method. During the consolidation process, no additional phases were found within the ceramic particles/matrix interfacial region. Using the ceramic TiH2 and SiC particles as the reinforcement cause notably strengthened the pure Al matrix (37% higher yield strength) without adversely affecting the plasticity, helping retain strain to fracture of about 50% for the sample. The yield strength of the samples was quantitatively approximated by examining their strengthening mechanisms via a number of simplified models available in the literature. The analyses found grain boundary and dislocation strengthening to be the most effective mechanisms for enhancing the strength of the samples; it was also found that the difference between the approximated and experimentally obtained overall yield strength was negligible.

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