Search results

Filters

  • Journals
  • Authors
  • Keywords
  • Date
  • Type

Search results

Number of results: 26
items per page: 25 50 75
Sort by:
Download PDF Download RIS Download Bibtex

Abstract

One of the ways to decrease thermal conductivity is nano structurization. Cobalt triantimonide (CoSb3) samples with added indium or tellurium were prepared by the direct fusion technique from high purity elements. Ingots were pulverized and re-compacted to form electrodes. Then, the pulsed plasma in liquid (PPL) method was applied. All materials were consolidated using rapid spark plasma sintering (SPS). For the analysis, methods such as X-ray diffraction (XRD), scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) with a laser flash apparatus (LFA) were used. For density measurement, the Archimedes’ method was used. Electrical conductivity was measured using a standard four-wire method. The Seebeck coefficient was calculated to form measured Seebeck voltage in the sample placed in a temperature gradient. The preparation method allowed for obtaining CoSb3 nanomaterial with significantly lower thermal conductivity (10 Wm–1K–1 for pure CoSb3 and 3 Wm–1K–1 for the nanostructured sample in room temperature (RT)). The size of crystallites (from SEM observations) in the powders prepared was about 20 nm, joined into larger agglomerates. The Seebeck coefficient, α, was about –200 µVK–1 in the case of both dopants, In and Te, in microsized material and about –400 µVK–1 for the nanomaterial at RT. For pure CoSb3, α was about 150 µVK–1 and it stood at –50 µVK–1 for nanomaterial at RT. In bulk nanomaterial samples, due to a decrease in electrical conductivity and inversion of the Seebeck coefficient, there was no increase in ZT values and the ZT for the nanosized material was below 0.02 in the measured temperature range, while for microsized In-doped sample it reached maximum ZT = 0.7 in (600K).

Go to article

Authors and Affiliations

R. Zybała
M. Schmidt
K. Kaszyca
M. Chmielewski
M.J. Kruszewski
M. Jasiński
M. Rajska
Ł. Ciupiński
Download PDF Download RIS Download Bibtex

Abstract

The mechanical behavior and the change of retained austenite of nanocrystalline Fe-Ni alloy have been investigated by considering the effect of various Ni addition amount. The nanocrystalline Fe-Ni alloy samples were rapidly fabricated by spark plasma sintering (SPS). The SPS is a well-known effective sintering process with an extremely short densification time not only to reach a theoretical density value but also to prevent a grain growth, which could result in a nanocrystalline structures. The effect of Ni addition on the compressive stress-strain behavior was analyzed. The variation of the volume fraction of retained austenite due to deformation was quantitatively measured by means of x-ray diffraction and microscope analyses. The strain-induced martensite transformation was observed in Fe-Ni alloy. The different amount of Ni influenced the rate of the strain-induced martensite transformation kinetics and resulted in the change of the work hardening during the compressive deformation.

Go to article

Authors and Affiliations

D. Park
S.-J. Oh
I.-J. Shon
S.-J. Lee
Download PDF Download RIS Download Bibtex

Abstract

This study aimed to prepare Zr55Cu30Al10Ni5 bulk amorphous alloys by spark plasma sintering of raw amorphous alloy powders and investigate their microstructure and micromechanical behaviors. When the sintering temperature ( Ts) was 675K, which was lower than the glass transition temperature ( Tg) of the material, the sintered sample was almost fully amorphous but the density was lower. However, when Ts was 705K, which was higher than Tg, partial crystallization occurred, but the density was higher. The hardness of the bonding zone of the sintered sample at 675K was 5.291 GPa due to the lower density, which was lower than that at 705K, and the hardness at 705K was 8.836 GPa. The generation of thermodynamically stable intermetallic phases, the hardness, and the elastic modulus of the samples sintered above Tg were higher due to the higher density.
Go to article

Authors and Affiliations

Yaqiong Ge
1
Zexin Chang
1
Wenxian Wang
1
Qingling Hou
1

  1. Taiyuan University of Science and Technology, College of Materials Science and Engineering, Taiyuan 030024, China
Download PDF Download RIS Download Bibtex

Abstract

In the paper the multiferroic (ferroelectric-ferromagnetic) composites based on ferroelectromagnetic/ferroelectric (BaFe1/2Nb1/2O3 (BFN)) powder and ferrite powder (zinc-nickel ferrite) were obtained by two technological methods. In the composite samples the ratio of the ferroelectromagnetic/ferroelectric powder to the magnetic powder was equal to 90:10. The ceramic powders were synthesized by the classical technological method using powder calcination/solid state synthesis, while densification of the composite powders (sintering) was carried by two different methods: (i) Free Sintering method (FS), and (ii) Spark Plasma Sintering (SPS).

At the work, a comparison of measurement results for composite samples obtained by two sintering methods was made. The studies included the following analysis: DTA, XRD, SEM, DC electrical conductivity, electric permittivity and magnetic properties. The result of measurements presented in the work revealed that the ceramic composite obtained by two different technological sintering method (classical technology – Free Sintering method and Spark Plasma Sintering technique) can be promising lead-free materials for functional applications, for example in sensors for magnetic and electric field.

Go to article

Authors and Affiliations

D. Bochenek
P. Niemiec
D. Brzezińska
Download PDF Download RIS Download Bibtex

Abstract

In this study, precisely controlled large scale gas atomization process was applied to produce spherical and uniform shaped high entropy alloy powder. The gas atomization process was carried out to fabricate CoCrFeNiMn alloy, which was studied for high ductility and mechanical properties at low temperatures. It was confirmed that the mass scale, single phase, equiatomic, and high purity spherical high entropy alloy powder was produced by gas atomization process. The powder was sintered by spark plasma sintering process with various sintering conditions, and mechanical properties were characterized. Through this research, we have developed a mass production process of high quality and spherical high entropy alloy powder, and it is expected to expand applications of this high entropy alloy into fields such as powder injection molding and 3D printing for complex shaped components.
Go to article

Authors and Affiliations

Tae Gyu Park
Sang Hyun Lee
Bin Lee
Hye Mi Cho
Won Jung Choi
Bum Sung Kim
Kwang Seon Shin
Taek-Soo Kim
Download PDF Download RIS Download Bibtex

Abstract

Fe-40wt% TiB2 nanocomposites were fabricated by mechanical activation and spark-plasma sintering of a powder mixture of iron boride (FeB) and titanium hydride (TiH2). The powder mixture of (FeB, TiH2) was prepared by high-energy ball milling in a planetary ball mill at 700 rpm for 3 h followed by spark-plasma sintering (SPS) at various conditions. Analysis of the change in relative sintered density and densification rate during sintering showed that a self-propagating high-temperature synthesis reaction occurs to form TiB2 from FeB and Ti. A sintered body with relative density higher than 98% was obtained after sintering at 1150°C for 5 and 15 min. The microstructural observation of sintered compacts with the use of FE-SEM and TEM revealed that ultrafine particulates with approximately 5 nm were evenly distributed in an Fe-matrix. A hardness value of 83 HRC was obtained, which is equivalent to that of conventional WC-20 Co systems.
Go to article

Authors and Affiliations

B.-W. Kim
X.-K. Huynh
J.-S. Kim
Download PDF Download RIS Download Bibtex

Abstract

The microstructure and corrosion properties of spark plasma sintered yttria dispersed and yttria free duplex and ferritic stainless samples were studied. Spark plasma sintering (SPS) was carried out at 1000°C by applying 50 MPa pressure with holding time of 5 minutes. Linear sweep voltammetry (LSV) tests were employed to evaluate pitting corrosion resistance of the samples. Corrosion studies were carried out in 0.5, 1 and 2 M concentration of NaCl and H2SO4 solutions at different quiet time of 2, 4, 6, 8 and 10 seconds. Yttria dispersed stainless steel samples show more resistance to corrosion than yttria free stainless steel samples. Pitting potential decreases with increase in reaction time from 2 to 10 seconds. Similarly, as concentration of NaCl and H2SO4 increases from 0.5 M to 2 M the corrosion resistance decrements due to the availability of more Cl¯ and SO4 2¯ ions at higher concentration.
Go to article

Authors and Affiliations

R. Shashanka
D. Chaira
Kumara Swamy B.E.
Download PDF Download RIS Download Bibtex

Abstract

The effects of different types of process control agents (PCA) on the microstructure evolution of Ni-based oxide dispersion-strengthened superalloy have been investigated. Alloy synthesis was performed on elemental powders having a nominal composition of Ni-15Cr-4.5Al-4W-2.5Ti-2Mo-2Ta-0.15Zr-1.1Y2O3 in wt % using high energy ball milling for 5 h. The prepared powders are consolidated by spark plasma sintering at 1000oC. Results indicated that the powder ball-milled with ethanol as PCA showed large particle size, low carbon content and homogeneous distribution of elemental powders compared with the powder by stearic acid. The sintered alloy prepared by ethanol as PCA exhibited a homogeneous microstructure with fine precipitates at the grain boundaries. The microstructural characteristics have been discussed on the basis of function of the PCA.

Go to article

Authors and Affiliations

Ju-Yeon Han
Hyunji Kang
Sung-Tag Oh
Download PDF Download RIS Download Bibtex

Abstract

The effects of carbon content on the austenite stability and strain-induced transformation of nanocrystalline Fe-11% Ni alloys were investigated using X-ray analysis and mechanical tests. The nanocrystalline FeNiC alloy samples were rapidly fabricated using spark plasma sintering because of the extremely short densification time, which not only helped attain the theoretical density value but also prevented grain growth. The increased austenite stability resulted from nanosized crystallites in the sintered alloys. Increasing compressive deformation increased the volume fraction of strain-induced martensite from austenite decomposition. The kinetics of the strain-induced martensite formation were evaluated using an empirical equation considering the austenite stability factor. As the carbon content increased, the austenite stability was enhanced, contributing to not only a higher volume fraction of austenite after sintering, but also to the suppression of its strain-induced martensite transformation.

Go to article

Authors and Affiliations

Seung-Jin Oh
Byoung-Cheol Kim
Man-Chul Suh
In-Jin Shon
Seok-Jae Lee
Download PDF Download RIS Download Bibtex

Abstract

New graphite tools were designed and produced to fabricate a semi-finished product from which nine cutting inserts were obtained in one spark plasma sintering process. As a result, WC-5Co cemented carbides were spark plasma sintered and the effect of various sintering parameters such as compacting pressure, heating rate and holding time on the main mechanical properties were investigated. It was shown that WC-5Co cemented carbides spark plasma sintered at 1200°C, 80 MPa, 400°C/min, for 5 min are characterized by the best relation of hardness (1861 ±10 HV30) and fracture toughness (9.30 MPa·m1/2). The microstructure of these materials besides the WC ceramic phase and Co binder phase consists of a synthesized Co3W3C complex phase. Comparison with a commercial WC-6Co cutting insert fabricated by conventional powder metallurgy techniques shows that spark plasma sintering is a very effective technique to produce materials characterized by improved mechanical properties.

Go to article

Authors and Affiliations

P. Siwak
D. Garbiec
Download PDF Download RIS Download Bibtex

Abstract

The β-phase Titanium (β-Ti) alloys have been under the spotlight in the recent past for their use as biomedical prosthetic materials owing to their excellent properties such as low elastic modulus, high corrosion resistance and tensile strength. Recently, Niobium (Nb) has gained a lot of attention as a β-phase stabilizing element in Ti alloys to replace Vanadium (V) due to its excellent solubility in Ti, low elastic modulus and biocompatibility. In this work, low cost Ti-20Nb binary alloy has been fabricated via powder metallurgy procedures. The blended powder mixtures of Ti and Nb were sintered at 900°C for 20 mins by the Spark Plasma Sintering (SPS) with an applied uniaxial pressure of 40 MPa. The heating rate was fixed at 50°C/min. The sintered alloy was subject to heat treatments at 1200°C in vacuum condition for various time durations. The characterizations of microstructure obtained during this process were done using FE-SEM, EDS and XRD. By increasing heat treatment time, as understood, the volume of residual Nb particles was decreased resulting in accelerated diffusion of Nb into Ti. Micro hardness of the alloy increased from 340 to 355 HV with the increase in β phase content from 30 to 45%. The resultant alloys had relatively high densities and homogenized microstructures of dispersed lamellar β grains in α matrix.

Go to article

Authors and Affiliations

M.A. Haq
S.F. Abbas
Nu Si A. Eom
T.S. Kim
B. Lee
K.-T. Park
B.S. Kim
Download PDF Download RIS Download Bibtex

Abstract

A TiC-Mo 2C-WC-Ni alloy cermet was fabricated by high-energy ball milling (HEBM) and consolidation through spark plasma sintering. The TiC-based powders were synthesized with different milling times (6, 12, 24, and 48 h) and subsequently consolidated by rapid sintering at 1300°C and a load of 60 MPa. An increase in the HEBM time led to improved sinterability as there was a sufficient driving force between the particles during densification. Core-rim structures such as (Ti, W)C and (Ti, Mo)C (rim) were formed by Ostwald ripening while inhibiting the coarsening of the TiC (core) grains. The TiC grains became refined (2.57 to 0.47 µm), with evenly distributed rims. This led to improved fracture toughness (11.1 to 14.8 MPa·m 1/2) owing to crack deflection, and the crack propagation resistance was enhanced by mitigating intergranular fractures around the TiC core.
Go to article

Authors and Affiliations

Jeong-Han Lee
1
ORCID: ORCID
Jae-Cheol Park
1
ORCID: ORCID
Hyun-Kuk Park
1
ORCID: ORCID

  1. Automotive Materials & Component R&D Group, Korea Institute of Industrial Technology, 6, Cheomdan-gwagiro 208-gil, Buk-gu, Gwangju, 61012, Korea
Download PDF Download RIS Download Bibtex

Abstract

An optimum route to fabricate the Ni-based superalloy with homogeneous dispersion of Y2O3 particles is investigated. Ni-based ODS powder was prepared by high-energy ball milling of gas-atomized alloy powders and Y2O3 particles treated with a high-pressure homogenizer. Decrease in particle size and improvement of dispersion stability were observed by high-pressure homogenization of as-received Y2O3 particles, presumably by the powerful cavitation forces and by collisions of the particles. Microstructural analysis for the ball-milled powder mixtures reveal that Ni-based ODS powders prepared from high-pressure homogenization of Y2O3 particles exhibited more fine and uniform distribution of Ni and Y elements compared to the as-received powder. These results suggested that high-pressure homogenization process is useful for producing Ni-based superalloy with homogeneously dispersed oxide particles.
Go to article

Bibliography

[1] T.M. Pollock, T. Sammy, J. Propul. Power 22, 361 (2006).
[2] W. Betteridge, S.W.K. Shaw, Mater. Sci. Technol. 3, 682 (1987).
[3] G . Quan, Y. Zhang, P. Zhang, Y. Mai, W. Wang, Trans. Nonferrous Met. Soc. China 31, 438 (2021).
[4] W. Sha, H.K.D.H. Bhadeshia, Metall. Mater. Trans. A 25, 705 (1994).
[5] G .W. Noh, Y.D. Kim, K.-A. Lee, H.-J. Kim, J. Korean Powder Metall. Inst. 27, 8 (2020).
[6] J.S. Benjamin, Metall. Trans. 1, 2943 (1970).
[7] S.K. Kang, R.C. Benn, Metall. Trans. A 16, 1285 (1985).
[8] Y.-I. Lee, E.S. Lee, S.-T. Oh, J. Nanosci. Nanotechnol. 21, 4955 (2021).
[9] J.H. Schneibel, S. Shim, Mater. Sci. Eng. A 488, 134 (2008).
[10] Q.X. Sun, T. Zhang, X.P. Wang, Q.F. Fang, T. Hao, C.S. Liu, J. Nucl. Mater. 424, 279 (2012).
[11] J. Kluge, G. Muhrer, M. Mazzotti, J. Supercrit. Fluids 66, 380 (2012).
[12] O . Mengual, G. Meunier, I. Cayré, K. Puech, P. Snabre, Talanta 50, 445 (1999).
[13] W.D. Pandolfe, J. Dispersion Sci. Technol. 2, 459 (1981).
[14] M. Luo, X. Qi, T. Ren, Y. Huang, A.A. Keller, H. Wang, B. Wu, H. Jin, F. Li, Colloids Surf. A 533, 9 (2017).
[15] C. Suryanarayana, Prog. Mater. Sci. 46, 1 (2001).
Go to article

Authors and Affiliations

Jongmin Byun
1
ORCID: ORCID
Young-In Lee
1
ORCID: ORCID
Sung-Tag Oh
1
ORCID: ORCID

  1. Seoul National University of Science and Technology, Department of Materials Science and Engineering & The Institute of Powder Technology, Seoul 01811, Republic of Korea
Download PDF Download RIS Download Bibtex

Abstract

In this study, a novel composite was fabricated by adding the Hafnium diboride (HfB2) to conventional WC-Co cemented carbides to enhance the high-temperature properties while retaining the intrinsic high hardness. Using spark plasma sintering, high density (up to 99.4%) WC-6Co-(1, 2.5, 4, and 5.5 wt. %) HfB2 composites were consolidated at 1300℃ (100℃/min) under 60 MPa pressure. The microstructural evolution, oxidation layer, and phase constitution of WC-Co-HfB2 were investigated in the distribution of WC grain and solid solution phases by X-ray diffraction and FE-SEM. The WC-Co-HfB2 composite exhibited improved mechanical properties (approximately 2,180.7 kg/mm2) than those of conventional WC-Co cemented carbides. The high strength of the fabricated composites was caused by the fine-grade HfB2 precipitate and the solid solution, which enabled the tailoring of mechanical properties.
Go to article

Bibliography

[1] J.H. Lee, I.H. Oh, J.H. Jang, S.K. Hong, H.K. Park, J. Alloys Compd. 786, 1-10 (2019).
[2] J. Garcia, V.C. Cipres, A. Blomqvist, B. Kaplan, Int. J. Refract. Met. Hard Mater. 80, 40-68 (2019).
[3] S.A. Shalmani, M. Sobhani, O. Mirzaee, M. Zakeri, Ceram. Int. 46 (16), 25106-25112 (2020).
[4] M .D. Brut, D. Tetard, C. Tixier, C. Faure, E. Chabas, 10th International Conference of the European Ceramic Society, Berlin, 1315-1320 (2007).
[5] A.K. Kumar, K. Kurokawa, Books: Tungsten carbide – Processing and applications, chapter 2: Spark plasma sintering of ultrafine WC powders: A combined kinetic and microstructural study (2012).
[6] R .G. Crookes, B. Marz, H. Wu, Mater. Des. 187, 108360 (2020).
[7] C. Bargeron, R. Benson, R. Newman, A.N. Jette, T.E. Phillips, Mater. Sci. (1993).
[8] C. Bagnall, J. Capo, W.J. Moorhead, Metallography Microstructure Analysis 7, 661-679 (2018).
Go to article

Authors and Affiliations

Hyun-Kuk Park
1
ORCID: ORCID
Ik-Hyun Oh
1
ORCID: ORCID
Ju-Hun Kim
1 2
ORCID: ORCID
Sung-Kil Hong
2
ORCID: ORCID
Jeong-Han Lee
1 2
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Smart Mobility Materials and Components R&D Group, 6, Cheomdan-gwa giro 208-gil, Buk-gu, Gwan g-Ju, 61012, Korea
  2. Chonnam National University, Materials Science & Engineering, 77, Yong-bongro, Buk-gu, Gwan g-ju, 61186, Korea
Download PDF Download RIS Download Bibtex

Abstract

WC-Co cemented carbides were consolidated using spark plasma sintering in the temperature 1400°C with transition metal carbides addition. The densification depended on exponentially as a function of sintering exponent. Moreover, the secondary (M, W)Cx phases were formed at the grain boundaries of WC basal facet. Corresponded, to increase the basal facets lead to the plastic deformation and oriented grain growth. A higher hardness was correlated with their grain size and lattice strain. We suggest that this is due to the formation energy of (M, W)Cx attributed to inhibit the grain growth and separates the WC/Co interface.
Go to article

Bibliography

[1] A.I. Gusev, A.A. Remple, A.J. Magerl, Disorder and order in strongly non-stoichiometric compounds: transition metal carbides, nitrides and oxide. Berlin: Springer; 607 (2001).
[2] T.A. Fabijanic, M. Kurtela, I. Skrinjaric, J. Potschke, M. Mayer, Metals 10, 224 (2020).
[3] X. Liu, X. Song, H. Wang, X. Liu, F. Tang, H. Lu, Acta Materialia 149, 164-178 (2018).
[4] H.O. Andren, Microstructures of cemented carbides, Mater. Des. 22, 491-498 (2001).
[5] C. Barbatti, J. Garcia, P. Brito, A.R. Pyzalla, Int. J. Refract. Met. Hard Mater. 27, 768-776 (2009).
[6] G .R. Antis, P. Chantikul, B.R. Lawn, D.B. Marshall, J. Am. Ceram. Soc. 64 (9), 533-538 (1981).
[7] Y.V. Milman, J. Superhard Mater. 36, 65-81 (2014).
[8] M . Christensen, G. Wahnstrom, Acta Materialia 52 (8), 2199-2207 (2004).
[9] Y . Peng, H. Miao, Z. Peng, Int. J. Refract. Met. Hard Mater. 39, 78-89 (2013).
Go to article

Authors and Affiliations

Jeong-Han Lee
1
ORCID: ORCID
Ik-Hyun Oh
1
ORCID: ORCID
Hyun-Kuk Park
1
ORCID: ORCID

  1. Korea Institute of Industrial Technology, Smart Mobility Materials and Components R&D Group, 6, Cheomdan-gwa giro 208-gil , Buk-gu, Gwang-Ju,61012, Korea
Download PDF Download RIS Download Bibtex

Abstract

In this work, we have designed a new high entropy alloy containing lightweight elements, e.g., Al, Fe, Mn, Ti, Cu, Si by high energy ball milling and spark plasma sintering. The composition of Si was kept at 0.75 at% in this study. The results showed that the produced AlCuFeMnTiSi0.75 high entropy alloy was BCC structured. The evolution of BCC1 and BCC2 phases was observed with increasing the milling time up to 60 h. The spark plasma sintering treatment of milled compacts from 650-950°C showed the phase separation of BCC into BCC1 and BCC2. The density and strength of these developed high entropy alloys (95-98%, and 1000 HV) improved with milling time and were maximum at 850°C sintering temperature. The current work demonstrated desirable possibilities of Al-Si based high entropy alloys for substitution of traditional cast components at intermediate temperature applications.
Go to article

Bibliography

[1] J.W. Yeh, S.K. Chen, S.J. Lin, J.Y. Gan, T.S. Chin, T.T. Shun, C.H. Tsau, S.Y. Chang, Adv. Eng. Mater. 6, 299 (2004).
[2] B.S. Murty, J.W. Yeh, S. Ranganathan, High-Entropy Alloys, 1st edn. Butterworth-Heinemann, Oxford 2014.
[3] B. Cantor, I.T.H. Chang, P. Knight, A.J.B. Vincent, Mater. Sci. Eng. A 375-377, 213 (2004).
[4] B. Cantor, Entropy 16, 4749 (2014). [5] W. Li, S. Cui, J. Han, C. Xu, Rare Met. 25, 133 (2006).
[6] A. Kumar, M. Gupta, Metals 6 (9), 199 (2016)
[7] K.M. Youssef, A.J. Zaddach, C. Niu, D.L. Irving, C.C. Koch, Mater. Res. Lett. 3, 95 (2014).
[8] K. Tseng, Y. Yang, C. Juan, T. Chin, C. Tsai, J. Yeh, Sci China Technol Sci. 61, 184 (2018).
[9] A. Sharma, D.U. Lim, J.P. Jung, Mater. Sci. Technol. 32 (8), 773 (2016).
[10] J.J. Chen, X. Zhou, W. Wang, B. Liu, Y. Lv, W. Yang, D. Xu, Y. Liu, J. Alloy. Compd. 760, 15 (2018).
[11] J.M. Torralba, P. Alvaredo, A.G. Junceda, Powder Met. 63, 227 (2020).
[12] B.D. Cullity, S.R. Stock, Elements of X-ray Diffraction, (3rd ed.), New York, Prentice Hall, 2001.
[13] M.J. Chae, A. Sharma, M.C. Oh, B. Ahn, Met. Mater. Int. 27, 629 (2021).
[14] A. Sharma, M.C. Oh, B. Ahn, Mater. Sci. Eng. A 797, 140066 (2020).
[15] J.M. Sanchez, I. Vicario, J. Albizuri, T. Guraya, E.M. Acuña, Sci Rep. 9, 6792 (2019).
[16] A. Kumar, P. Dekhne, A.K. Swarnakar, M. Chopkar, Mater. Res. Exp. 6, 026532 (2019).
Go to article

Authors and Affiliations

Minsu Kim
1
Ashutosh Sharma
1
ORCID: ORCID
Myoung Jin Chae
1
Hansung Lee
1
ORCID: ORCID
Byungmin Ahn
1
ORCID: ORCID

  1. Ajou University, Department of Materials Science and Engineering and Department of Energy Systems Research, 206 Worldcup-ro, Suwon-si, Gyeonggi, 16499, Korea
Download PDF Download RIS Download Bibtex

Abstract

Spark Plasma Sintering (SPS) is identified as a suitable technique to prepare the alumina titanium carbide composite to overcome the difficulty in fabricating it through other consolidation method. The present work focuses on the fabrication and characterization of a series of titanium carbide reinforced alumina ceramic composites using a spark plasma sintering process. The titanium carbide reinforcement on the alumina matrix is varied between 20 and 35 wt.%, in order to improve the electrical conductivity and fracture toughness of the composites. The particle size of the starting powders at received and ball milled conditions was analysed through Particle size analyser and Scanning Electron Microscope (SEM). Microstructural analysis revealed that the TiC reinforcement is uniformly dispersed in the sintered composite. XRD report showed that α-alumina and titanium carbide were the two dominant phases without the formation of any reaction phases. Further, the correlation between mechanical and physical properties of the prepared composite was investigated as a function of TiC. Various fracture toughening indicators like crack deflection, bridging and branching were analysed by Vicker’s indentation method. Electrical resistivity of the sintered compact decreases proportionally with the increase in titanium carbide constituents. Maximum density (98.80%) and hardness (20.56 GPa) was obtained for 30 wt. % reinforced composite. Almost 40% improvement in fracture toughness is noted for 25 wt. % reinforced composite. This work demonstrates the synthesis and fabrication of alumina titanium carbide composites at low temperature via SPS resulted in obtaining an intact compact with improved mechanical and electrical properties.
Go to article

Bibliography

[1] Y. Tamura, B.M. Moshtaghioun, D.G. Garcia, A.D. Rodriguez, Ceram. Int. 43, 658-663 (2017).
[2] Y. Wang, F. Luo, W. Zhou, D. Zhu, J. Electron. Mater. 46 (8), 5225-5231 (2017).
[3] G.M. Asmelash, O. Mamat, F. Ahmad, A.K.P. Rao, J. Adv. Ceram. 4 (3), 190-198 (2015).
[4] S. Ghanizadeh, S. Grasso, P. Ramanujam, B. Vaidhyanathan, J. Binner, P. Brown, J. Goldwasser, Ceram. Int. 43, 275-281 (2017).
[5] E .S. Gevorkyan, M. Rucki, A.A. Kagramanyan, V.P. Nerubatskiy, Int. J. Refract. Met. H. 89, 336-339 (2019).
[6] C. Sun, Y. Li, Y. Wang, L. Zhu, Q. Jiang, Y. Miao, X. Chen, Ceram. Int. 40, 12723-12728 (2014).
[7] U .S. Radloff, F. Kern, R. Gadow, J. Eur. Ceram. Soc. 38, 4003- 4013 (2018).
[8] C. Tuzemen, B. Yavas, I. Akin, O. Yucel, F. Sahin, G. Goller, J. Alloy. Compd. 781, 433-439 (2019).
[9] I. Farias, L. Olmos, O. Jimenez, M. Flores, A. Braem, J. Vleugels, Trans. Nonferrous Met. Soc. China 29, 1653-1664 (2019).
[10] L.M. Luo, J.B. Chen, H.Y. Chen, G.N. Luo, X.Y. Zhu, J.G. Cheng, X. Zan, Y.C. Wu, Fusion Eng. Des. 90, 62-66 (2015).
[11] J . Zhang, L. Wang, W. Jiang, L. Chen, Mat. Sci. Eng. A. 487, 137-143 (2008).
[12] H . Istgaldi, M.S. Asl, P. Shahi, B. Nayebi, Z. Ahmadi, Ceram. Int. (2019). DOI: https://doi.org/10.1016/j.ceramint.2019.09.287
[13] A.S. Namini, Z. Ahmadi, A. Babapoor, M. Shokouhimehr, M.S. Asl, Ceram. Int. 45, 2153-2160 (2019).
[14] D. Chakravarthy, S. Roy, P.K. Das, Bull. Mater. Sci. 28, 3, 227-231 (2005).
[15] L. Wang, X. Shu, X. Lu, Y. Wu, Y. Ding, S. Zhang, Mater. Lett. 196, 403-405 (2017).
[16] L. Cheng, Z. Xie, G. Liu, W. Liu, W. Xue, J. Eur. Ceram. Soc. 32, 3399-3406 (2012).
[17] N. Shanbhog, K. Vasanthakumar, N. Arunachalam, S.R. Bakshi, Int. J. Refract. Met. H. 84, 104979-104988 (2019).
[18] B.L. Madej, D. Garbiec, M. Madej, Vacuum. 164, 250-255 (2019).
[19] Y.F. Zhou, Z.Y. Zhao, X.Y. Tan, L.M. Luo, Y. Xu, X. Zan, Q. Xu, K. Tokunaga, X.Y. Zhu, Y.C. Wu, Int. J. Refract. Met. H. 79, 95- 101 (2019).
[20] P. Zhanga, C. Chena, Z. Chena, C. Shena, P. Fenga, Vacuum 164, 286-292 (2019).
[21] C. Luo, Y. Wang, J. Xu, G. Xu, Z. Yan, J. Li, H. Li, H. Lu, J. Suo, Int. J. Refract. Met. H. 81, 27-35 (2019).
[22] B.B. Bokhonov, M.A. Korchagin, A.V. Ukhina, D.V. Dudinaa, Vacuum, 157, 210-215 (2018).
[23] A. Teber, F. Schoenstein, F. Tetard, M. Abdellaoui, N. Jouini, Int. J. Refract. Met. H. 30, 64-70 (2012).
[24] M . Demuynck, J.P. Erauw, O.V. Biest, F. Delannay, F. Cambier, J. Eur. Ceram. Soc. 32, 1957-1964 (2012).
[25] Y.W. Kim, J.G. Lee, J. Am. Ceram. Soc. 12, 1333-37 (1989).
[26] R .A. Cutler, A.C. Hurford, Mat. Sci. Eng. A., 105/106, 183-192 (1988).
[27] J .H. Zhang, T.C. Lee, W.S. Lau, J. Mater. Process. Tech. 63, 908- 912 (1997).
[28] Z. Fu, R. Koc, Ceram. Int. 43, 17233-17237 (2017).
[29] R . Kumar, A.K. Chaubey, S. Bathula, K.G. Prashanth, A. Dhar, J. Mater. Eng. Perform. 27, 997-1004 (2018).
[30] O . Guillon, J.G. Julian, B. Dargatz, T. Kessel, G. Schierning, J. Rathel, M. Herrmann. Adv. Eng. Mater. 16, 830-849 (2014).
[31] D. Zhang, L. Ye, D. Wang, Y. Tang, S. Mustapha, Y. Chen, Composites: Part A. 43, 1587-1598 (2012).
[32] T. Fujii, K. Tohgo, P.B. Putra, Y. Shimamura, J. Mech. Behav. Biomed. 19, 45-53 (2019).
[33] T. Thomas, C. Zhang, A. Sahu, P. Nautiyal, A. Loganathan, T. Laha, B. Boel, A. Agarwal, Mat. Sci. Eng. A. 728, 45-53 (2018).
[34] L.K. Singh, A. Bhadauria, T. Laha, J. Mater. Res. Technol. 8, 503-512 (2019).
[35] T. Fujii, K. Tohgo, M. Iwao, Y. Shimamura, J. Alloy. Compd. 744, 759-768 (2018).
[36] S. Xiang, S. Ren, Y. Liang, X. Zhang, Mat. Sci. Eng. A. 768, 138459 (2019).
[37] M .R. Akbarpour, S. Alipour, Ceram. Int. 43, 13364-13370 (2017).
[38] W.R. Ilaham, L.K. Singh, T. Laha, Fusion Eng. Des. 138, 303-312 (2019).
[39] U . Sabu, B. Majumdar, Bhaskar P. Saha & D. Das, Trans. Ind. Ceram. Soc. 77, 1-7 (2018)
[40] L. Zhang, R.V. Koka, Mater. Chem. Phys. 57, 23-32 (1998).
[41] J . Langer, M.J. Hoffmann, O. Guillon, Acta. Mater. 57, 5454-5465 (2009).
[42] A. Babapoor, M.S. Asl, Z. Ahmadi, A.S. Namini, Ceram. Int. 44, 14541-14546 (2018).
[43] F. Balima, A. Largeteau, Scr. Mater. 158, 20-23 (2019).
[44] W.H. Lee, J.G. Seong, Y.H. Yoon, C.H. Jeong, C.J.V. Tyne, H.G. Lee, S.Y. Chang, Ceram. Int. 45, 8108-8114 (2019).
Go to article

Authors and Affiliations

G. Selvakumar
1
S. Prakash
1
K. Rajkumar
1

  1. Department of Mechanical Engineering, Sri Sivasubramaniya Nadar College of Engineering, Chennai, India
Download PDF Download RIS Download Bibtex

Abstract

Doping is one of the possible ways to significantly increase the thermoelectric properties of many different materials. It has been confirmed that by introducing bismuth atoms into Mg sites in the Mg2Si compound, it is possible to increase career concentration and intensify the effect of phonon scattering, which results in remarkable enhancement in the figure of merit (ZT) value. Magnesium silicide has gained scientists’ attention due to its nontoxicity, low density, and inexpensiveness. This paper reports on our latest attempt to employ ultrafast selfpropagating high-temperature synthesis (SHS) followed by the spark plasma sintering (SPS) as a synthesis process of doped Mg2Si. Materials with varied bismuth doping were fabricated and then thoroughly analyzed with the laser flash method (LFA), X-ray diffraction (XRD), scanning electron microscopy (SEM) with an integrated energy-dispersive spectrometer (EDS). For density measurement, the Archimedes method was used. The electrical conductivity was measured using a standard four-probe method. The Seebeck coefficient was calculated from measured Seebeck voltage in the sample subjected to a temperature gradient. The structural analyses showed the Mg2Si phase as dominant and Bi2Mg3 located at grain boundaries. Bismuth doping enhanced ZT for every dopant concentration. ZT = 0:44 and ZT=0.38 were obtained for 3wt% and 2wt% at 770 K, respectively.
Go to article

Authors and Affiliations

Bartosz Bucholc
1
ORCID: ORCID
Kamil Kaszyca
1
ORCID: ORCID
Piotr Śpiewak
2
ORCID: ORCID
Krzysztof Mars
3
ORCID: ORCID
Mirosław J. Kruszewski
2
ORCID: ORCID
Łukasz Ciupiński
2
ORCID: ORCID
Krystian Kowiorski
1
ORCID: ORCID
Rafał Zybała
1 2
ORCID: ORCID

  1. Łukasiewicz Research Network - Institute of Microelectronics and Photonics, Aleja Lotników 32/46, 02-668 Warsaw, Poland
  2. Faculty of Materials Science and Engineering, Warsaw University of Technology, Wołoska 141, 02-507 Warsaw, Poland
  3. Faculty of Materials Science and Ceramic, AGH University of Science and Technology, Kraków, Al. Mickiewicza 30, 30-059, Poland
Download PDF Download RIS Download Bibtex

Abstract

In this work, the 316L austenitic steel based milled and sintered composites with 0.33 wt% and 1 wt% SiC ultra-fine particles addition have been prepared. The high efficient attrition milling provided an efficient size reduction of the 316L steel grains and homogeneous distribution of the SiC nanoparticles before sintering process. Spark plasma sintering (SPS) was used for compaction of milled powder mixtures. The effect of SiC addition on the milling efficiency and the structure of the composites have been studied. It was found that the amount of ceramic addition did not influence the efficiency of milling process, powder mixtures with flake like grains have been obtained. On the other hand, the intensive milling assured an optimal coverage of 316L stainless steel grains with submicron sized ceramic particles in both cases. The sintered composites showed high densities with the presence of small amount of closed porosities. Structural, mechanical and tribological examinations of 316L/SiC composites have been performed and presented.

Go to article

Authors and Affiliations

Haroune Rachid Ben Zine
Filiz Cinar Sahin
Zsolt Czigány
Katalin Balázsi
Csaba Balázsi
Download PDF Download RIS Download Bibtex

Abstract

The effect of TiC content on the microstructure and mechanical properties of a nanocrystalline Fe-Mn alloy was investigated by XRD analysis, TEM observation, and mechanical tests. A sintered Fe-Mn alloy sample with nano-sized crystallites was obtained using spark plasma sintering. Crystallite size, which is used as a hardening mechanism, was measured by X-ray diffraction peak analysis. It was observed that the addition of TiC influenced the average size of crystallites, resulting in a change in austenite stability. Thus, the volume fraction of austenite at room temperature after the sintering process was also modified by the TiC addition. The martensite transformation during cooling was suppressed by adding TiC, which lowered the martensite start temperature. The plastic behavior and the strain-induced martensite kinetics formed during plastic deformation are discussed with compressive stress-strain curves and numerical analysis for the transformation kinetics.

Go to article

Authors and Affiliations

Junhyub Jeon
ORCID: ORCID
Seunggyu Choi
Namhyuk Seo
ORCID: ORCID
Young Hoon Moon
In-Jin Shon
Seok-Jae Lee
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

We investigated the austenite stability and mechanical properties in FeMnNiC alloy fabricated by spark plasma sintering. The addition of Mn, Ni, and C, which are known austenite stabilizing elements, increases its stability to a stable phase existing above 910°C in pure iron; as a result, austenitic microstructure can be observed at room temperature, depending on the amounts of Mn, Ni, and C added. Depending on austenite stability and the volume fraction of austenite at a given temperature, strain-induced martensite transformation during plastic deformation may occur. Both stability and the volume fraction of austenite can be controlled by several factors, including chemical composition, grain size, dislocation density, and so on. The present study investigated the effect of carbon addition on austenite stability in FeMnNi alloys containing different Mn and Ni contents. Microstructural features and mechanical properties were analyzed with regard to austenite stability.

Go to article

Authors and Affiliations

Seunggyu Choi
Junhyub Jeon
ORCID: ORCID
Namhyuk Seo
ORCID: ORCID
Young Hoon Moon
In-Jin Shon
Seok-Jae Lee
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

This research describes effects of Si addition on microstructure and mechanical properties of the Al-Cr based alloys prepared manufactured using gas atomization and SPS (Spark Plasma Sintering) processes. The Al-Cr-Si bulks with high Cr and Si content were produced successfully using SPS sintering process without crack and obtained fully dense specimens close to nearly 100% T. D. (Theoretical Density). Microstructure of the as-atomized Al-Cr-Si alloys with high contents of Cr and Si was composed multi-phases with hard and thermally stable such as Al13Cr4Si4, AlCrSi, Al8Cr5 and Cr3Si intermetallic compounds. The average hardness values were 703 Hv for S5, 698 Hv for S10 and 824 Hv for S20 alloy. Enhancement of hardness value was resulted from the formation of the multi-intermetallic compound with hard and thermally stable and fine microstructure by the addition of high Cr and Si using rapid solidification and SPS process.

Go to article

Authors and Affiliations

Yong-Ho Kim
ORCID: ORCID
Ik-Hyun Oh
ORCID: ORCID
Hyo-Sang Yoo
ORCID: ORCID
Hyun-Kuk Park
ORCID: ORCID
Jung-Han Lee
Hyeon-Taek Son
ORCID: ORCID
Download PDF Download RIS Download Bibtex

Abstract

Due to air pollution, global warming and energy shortage demands new clean energy conversion technologies. The conversion of industrial waste heat into useful electricity using thermoelectric (TE) technology is a promising method in recent decades. Still, its applications are limited by the low efficiency of TE materials in the operating range between 400-600 K. In this work, we have fabricated Cu0.005Bi0.5Sb1.495Te3 powder using a single step gas atomization process followed by spark plasma sintering at different temperatures (623, 673, 723, and 773 K), and their thermoelectric properties were investigated. The variation of sintering temperature showed a significant impact on the grain size. The Seebeck coefficient values at room temperature increased significantly from 127 μVK to 151 μV/K with increasing sintering temperature from 623 K to 723 K due to decreased carrier concentration. The maximum ZT values for the four samples were similar in the range between 1.15 to 1.18 at 450 K, which suggest these materials could be used for power generation in the mid-temperature range (400-600 K).

Go to article

Authors and Affiliations

Chul-Hee Lee
Peyala Dharmaiah
Jun-Woo Song
Kwang-Yong Jeong
Soon-Jik Hong

This page uses 'cookies'. Learn more