Spark plasma sintering

Spark plasma sintering (SPS),"Field-Assisted Sintering Technology / Spark Plasma Sintering: Mechanisms,Materials, and Technology Developments", By O. Guillon et al., Advanced Engineering Materials 2014, DOI: 10.1002/adem.201300409, http://onlinelibrary.wiley.com/doi/10.1002/adem.201300409/epdf also known as field assisted sintering technique (FAST)[https://www.mtm.kuleuven.be/Onderzoek/Ceramics/SPS/ KU Leuven - SPS process modeling] or pulsed electric current sintering (PECS), or plasma pressure compaction (P2C)[http://www.sps-p2c.com 'sps-p2c] is a sintering technique.

The main characteristic of SPS is that the pulsed or unpulsed DC or AC current directly passes through the graphite die, as well as the powder compact, in case of conductive samples. Joule heating has been found to play a dominant role in the densification of powder compacts, which results in achieving near theoretical density at lower sintering temperature compared to conventional sintering techniques.{{cite journal | last1 = Sairam | first1 = K. | last2 = Sonber | first2 = J.K. | last3 = Subramanian | first3 = C. | last4 = Fotedar | first4 = R.K. | last5 = Nanekar | first5 = P. | last6 = Hubli | first6 = R.C. | title = Influence of spark plasma sintering parameters on densification and mechanical properties of boron carbide | journal = International Journal of Refractory Metals and Hard Materials | volume = 42| pages = 185–192| doi=10.1016/j.ijrmhm.2013.09.004| date = January 2014 }} The heat generation is internal, in contrast to the conventional hot pressing, where the heat is provided by external heating elements. This facilitates a very high heating or cooling rate (up to 1000 K/min), hence the sintering process generally is very fast (within a few minutes). The general speed of the process ensures it has the potential of densifying powders with nanosize or nanostructure while avoiding coarsening which accompanies standard densification routes. This has made SPS a good method for preparation of a range of materials with enhanced magnetic,{{cite journal|last1=Aubert|first1=A.|last2=Loyau|first2=V.|last3=Mazaleyrat|first3=F.|last4=LoBue|first4=M.|title=Uniaxial anisotropy and enhanced magnetostriction of CoFe2O4 induced by reaction under uniaxial pressure with SPS|journal=Journal of the European Ceramic Society|date=2017|volume=37|issue=9|pages=3101–3105|doi=10.1016/j.jeurceramsoc.2017.03.036|url=https://hal.archives-ouvertes.fr/hal-01636264|arxiv=1803.09656|s2cid=118914808}} magnetoelectric,{{cite journal|last1=Aubert|first1=A.|last2=Loyau|first2=V.|last3=Mazaleyrat|first3=F.|last4=LoBue|first4=M.|title=Enhancement of the Magnetoelectric Effect in Multiferroic CoFe2O4/PZT Bilayer by Induced Uniaxial Magnetic Anisotropy|journal=IEEE Transactions on Magnetics|date=2017|volume=53|issue=11|pages=1–5|doi=10.1109/TMAG.2017.2696162|url=https://hal.archives-ouvertes.fr/hal-01636268|arxiv=1803.09677|s2cid=25427820}} piezoelectric,Li et al, Ferroelectric and Piezoelectric Properties of Fine-Grained Na0.5K0.5NbO3 Lead-Free Piezoelectric Ceramics Prepared by Spark Plasma Sintering, Journal of the American Ceramic Society, 89, 2, 706–709, (2006) thermoelectric,{{cite journal | last1 = Wang | display-authors = etal | year = 2006 | title = High-performance Ag[sub 0.8]Pb[sub 18+x]SbTe[sub 20] thermoelectric bulk materials fabricated by mechanical alloying and spark plasma sintering| journal = Applied Physics Letters | volume = 88 | issue = 9| page = 092104 | doi = 10.1063/1.2181197 }} optical,{{cite journal | last1 = Kim | display-authors = etal | year = 2007 | title = Spark plasma sintering of transparent alumina| journal = Scripta Materialia | volume = 57 | issue = 7| pages = 607–610 | doi = 10.1016/j.scriptamat.2007.06.009 }} shock compression,{{Cite journal |last1=Turnage |first1=Scott A. |last2=Clayton |first2=John D. |last3=Rodriguez |first3=Jonathan |last4=Scharf |first4=Thomas W. |last5=Williams |first5=Cyril L. |date=2024-01-24 |title=Planar shock compression of spark plasma sintered B4C and B4C–TiB2 ceramic composites |url=https://pubs.aip.org/aip/adv/article/14/1/015053/3064037/Planar-shock-compression-of-spark-plasma-sintered |journal=AIP Advances |volume=14 |issue=1 |pages=015053 |doi=10.1063/5.0181329 |issn=2158-3226|doi-access=free }} or biomedical{{cite journal | last1 = Gu | display-authors = etal | year = 2002 | title = Spark plasma sintering of hydroxyapatite powders| journal = Biomaterials | volume = 23 | issue = 1| pages = 37–43 | doi = 10.1016/S0142-9612(01)00076-X | pmid = 11762852 }} properties. SPS is also used for sintering of carbon nanotubes{{cite journal | last1 = Talemi | display-authors = etal | year = 2012 | title = Fusion of carbon nanotubes for fabrication of field emission cathodes| journal = Carbon | volume = 50 | issue = 2| pages = 356–361 | doi = 10.1016/j.carbon.2011.07.058 | bibcode = 2012Carbo..50..356H }} for development of field electron emission electrodes. Functioning of SPS systems is schematically explained in a video link.[http://sps-p2c.com/products/ 'SPS-How it Works?] While the term "spark plasma sintering" is commonly used, the term is misleading since neither a spark nor a plasma is present in the process.{{cite journal | last1 = Hulbert | first1 = D. M. | last2 = Anders | first2 = A. | last3 = Dudina | first3 = D. V. | last4 = Andersson | first4 = J. | last5 = Jiang | first5 = D. | last6 = Unuvar | first6 = C. | last7 = Anselmi-Tamburini | first7 = U. | last8 = Lavernia | first8 = E. J. | last9 = Mukherjee | first9 = A. K. | year = 2008 | title = The absence of plasma in spark plasma sintering | url = https://www.escholarship.org/uc/item/2c14z63t| journal = J. Appl. Phys. | volume = 104 | issue = 3| pages = 033305–7 | doi=10.1063/1.2963701| bibcode = 2008JAP...104c3305H | s2cid = 54726651 }} It has been experimentally verified that densification is facilitated by the use of a current. SPS can be used as a tool for the creation of functionally graded soft-magnetic materials and it is useful in accelerating the development of magnetic materials.V. Chaudhary, L. P. Tan, V. K. Sharma, R. V. Ramanujan, Accelerated study of magnetic Fe-Co-Ni alloys through compositionally graded spark plasma sintered samples, Journal of Alloys and Compounds, 869, 159318 (2021), https://doi.org/10.1016/j.jallcom.2021.159318 It has been found that this process improves the oxidation resistance {{Cite journal |last1=Karimi |first1=Hadi |last2=Hadi |first2=Morteza |last3=Ebrahimzadeh |first3=Iman |last4=Farhang |first4=Mohammad Reza |last5=Sadeghi |first5=Mohsen |date=2018-10-01 |title=High-temperature oxidation behaviour of WC-FeAl composite fabricated by spark plasma sintering |url=https://www.sciencedirect.com/science/article/pii/S0272884218316110 |journal=Ceramics International |language=en |volume=44 |issue=14 |pages=17147–17153 |doi=10.1016/j.ceramint.2018.06.168 |s2cid=140057751 |issn=0272-8842|url-access=subscription }} and wear resistance{{Cite journal |last1=Karimi |first1=Hadi |last2=Hadi |first2=Morteza |date=2020-08-01 |title=Effect of sintering techniques on the structure and dry sliding wear behavior of WC-FeAl composite |url=https://www.sciencedirect.com/science/article/pii/S0272884220310981 |journal=Ceramics International |language=en |volume=46 |issue=11, Part B |pages=18487–18497 |doi=10.1016/j.ceramint.2020.04.154 |s2cid=219077175 |issn=0272-8842|url-access=subscription }} of sintered tungsten carbide composites compared to conventional consolidation methods.

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