ultrasonic atomization

File:Ultrasonic atomization principle.jpg

The formation of droplets during ultrasonic atomization remains complex and not fully understood, though several theories attempt to explain it. One leading theory, the capillary wave hypothesis by Lang,{{Cite journal |last=Lang |first=Robert J. |date=1962-01-01 |title=Ultrasonic Atomization of Liquids |url=https://pubs.aip.org/jasa/article/34/1/6/734260/Ultrasonic-Atomization-of-Liquids |journal=The Journal of the Acoustical Society of America |language=en |volume=34 |issue=1 |pages=6–8 |doi=10.1121/1.1909020 |bibcode=1962ASAJ...34....6L |issn=0001-4966|url-access=subscription }} suggests that droplets form at the peaks of capillary waves on the liquid surface. Lang developed a formula that relates droplet size to capillary wavelength. The average diameter estimation was obtained using a constant that was later adjusted by Yasuda{{Cite journal |last1=Yasuda |first1=Keiji |last2=Bando |first2=Yoshiyuki |last3=Yamaguchi |first3=Soyoko |last4=Nakamura |first4=Masaaki |last5=Oda |first5=Akiyoshi |last6=Kawase |first6=Yasuhito |date=January 2005 |title=Analysis of concentration characteristics in ultrasonic atomization by droplet diameter distribution |url=https://linkinghub.elsevier.com/retrieve/pii/S1350417704001026 |journal=Ultrasonics Sonochemistry |language=en |volume=12 |issue=1–2 |pages=37–41 |doi=10.1016/j.ultsonch.2004.05.008|pmid=15474950 |bibcode=2005UltS...12...37Y |url-access=subscription }} to better predict smaller droplet sizes in the micrometer range. This prediction aligns well with observations from laser diffraction, though other methods have detected finer droplets that Lang's model does not account for. An alternative theory, proposed by Sollner,{{Cite journal |last=Söllner |first=Karl |date=1936 |title=The mechanism of the formation of fogs by ultrasonic waves |url=https://xlink.rsc.org/?DOI=TF9363201532 |journal=Trans. Faraday Soc. |language=en |volume=32 |pages=1532–1536 |doi=10.1039/TF9363201532 |issn=0014-7672|url-access=subscription }} is the cavitation hypothesis. This theory links droplet formation to cavitation—when bubbles in the liquid rapidly form and collapse, creating shockwaves that break apart the liquid surface into droplets. Sollner's findings suggest cavitation is essential for dispersing liquids and shares similarities with emulsion formation. A combined theory was later proposed by Bograslavski and Eknadiosyants,{{Cite journal |last=Eknadiosyants |first=O.K. |date=January 1969 |title=Role of cavitation in the process of liquid atomization in an ultrasonic fountain |url=https://linkinghub.elsevier.com/retrieve/pii/0041624X69905605 |journal=Ultrasonics |language=en |volume=7 |issue=1 |pages=78 |doi=10.1016/0041-624X(69)90560-5|url-access=subscription }} suggesting that both mechanisms work together: shockwaves from cavitation enhance the breaking of capillary wave crests, leading to droplet formation. However, this combined theory faces some scepticism, as cavitation requires high power at MHz frequencies, which some researchers argue may be too high to support this mechanism effectively in practice.{{Citation |last=Nii |first=Susumu |title=Ultrasonic Atomization |date=2016 |work=Handbook of Ultrasonics and Sonochemistry |pages=239–257 |url=http://link.springer.com/10.1007/978-981-287-278-4_7 |access-date=2024-11-08 |place=Singapore |publisher=Springer Singapore |language=en |doi=10.1007/978-981-287-278-4_7 |isbn=978-981-287-277-7|url-access=subscription }}

The phenomenon of ultrasonic atomization was first reported by Wood and Loomis in 1927.{{Cite journal |last1=Wood |first1=R.W. |last2=Loomis |first2=Alfred L. |date=September 1927 |title=XXXVIII. The physical and biological effects of high-frequency sound-waves of great intensity |url=http://www.tandfonline.com/doi/abs/10.1080/14786440908564348 |journal=The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science |language=en |volume=4 |issue=22 |pages=417–436 |doi=10.1080/14786440908564348 |issn=1941-5982|url-access=subscription }} They observed that a fine mist was produced from the liquid surface when a liquid layer was subjected to high-frequency sound waves. Wood and Loomis's work hinted at a variety of applications for ultrasonics, many of which became realities in later decades, with the development in the scope of ultrasound generation (piezoelectricity), transfer (sonotrode materials), and control (horn analyzers).

First commercial application of ultrasonic atomization effect was nebulizers. Ultrasonic nebulizers made their first appearance in 1949, initially designed as humidifiers. Medical professionals quickly recognized their potential for delivering therapeutic aerosols suitable for inhalation,{{Cite journal |last=Ari |first=Arzu |date=2014-05-12 |title=Jet, Ultrasonic, and Mesh Nebulizers: An Evaluation of Nebulizers for Better Clinical Outcomes |url=https://www.journalagent.com/z4/download_fulltext.asp?pdir=eurasianjpulmonol&plng=eng&un=SOLUNUM-00087 |journal=Eurasian Journal of Pulmonology |volume=16 |issue=1 |pages=1–7 |doi=10.5152/ejp.2014.00087|doi-access=free }} leading to the incorporation of medications into the nebulization process.{{Cite journal |last1=Yeo |first1=Leslie Y |last2=Friend |first2=James R |last3=McIntosh |first3=Michelle P |last4=Meeusen |first4=Els NT |last5=Morton |first5=David AV |date=June 2010 |title=Ultrasonic nebulization platforms for pulmonary drug delivery |url=http://www.tandfonline.com/doi/full/10.1517/17425247.2010.485608 |journal=Expert Opinion on Drug Delivery |language=en |volume=7 |issue=6 |pages=663–679 |doi=10.1517/17425247.2010.485608 |pmid=20459360 |issn=1742-5247|url-access=subscription }} Ultrasonic nebulizers have been utilized for various respiratory diseases, including asthma and cystic fibrosis. Their ability to deliver medications directly to the lungs has made them a valuable tool in managing these conditions{{Cite journal |last=Dessanges |first=Jean-François |date=March 2001 |title=A History of Nebulization |url=http://www.liebertpub.com/doi/10.1089/08942680152007918 |journal=Journal of Aerosol Medicine |language=en |volume=14 |issue=1 |pages=65–71 |doi=10.1089/08942680152007918 |pmid=11495487 |issn=0894-2684|url-access=subscription }}

In the late 20th century, scientists exploring nanoparticle synthesis via spray pyrolysis began to testsee ultrasonic atomization as a promising technique for precursor droplet formation such as noble metal based salts solutions. Known as ultrasonic spray pyrolysis (USP), this technique allowed for finer control over particle size as it strongly depends on the frequency, making it particularly suited for nanomaterials used in electronic devices, solar cells, and batteries. By the 1980s and 1990s, ultrasonic atomization was gaining ground as researchers demonstrated its utility in producing complex oxides and other materials essential for energy storage like lithium-ion batteries.{{Citation |last=Nii |first=Susumu |title=Ultrasonic Atomization |date=2016 |work=Handbook of Ultrasonics and Sonochemistry |pages=239–257 |url=https://link.springer.com/referenceworkentry/10.1007/978-981-287-278-4_7 |access-date=2024-11-03 |place=Singapore |publisher=Springer |language=en |doi=10.1007/978-981-287-278-4_7 |isbn=978-981-287-278-4|url-access=subscription }} By the early 2000s, this method was integral to industries seeking uniform coatings and nanoparticle films, demonstrating the impact of ultrasonic atomization on industrial manufacturing.{{Cite journal |last1=Ramisetty |first1=Kiran. A. |last2=Pandit |first2=Aniruddha. B. |last3=Gogate |first3=Parag. R. |date=January 2013 |title=Investigations into ultrasound induced atomization |url=https://linkinghub.elsevier.com/retrieve/pii/S1350417712000909 |journal=Ultrasonics Sonochemistry |language=en |volume=20 |issue=1 |pages=254–264 |doi=10.1016/j.ultsonch.2012.05.001|pmid=22672979 |bibcode=2013UltS...20..254R |url-access=subscription }}

File:Ultrasonic atomizer - first.pngIn 1965, Pohlman and Stamm published a book, which marked a contribution to the field of ultrasonic atomization by identifying and describing the parameters influencing the process such as viscosity, capillary wavelength, surface tension and amplitude. One of the key chapters in the book, titled "5.1 Vernebelung geschmolzener Metalle," detailed the first experiments on the high temperature ultrasonic atomization in which molten metals were used. They discussed its potential technical applications as well as limitations stating that the transition from successful laboratory experiments to a usable technical plant has not yet been found due to issues with conciliation wettability and sonotrode durability. They were able to atomize lead at 350 °C and showcased the damage to the sonotrode induced by cavitation. In 1967, Lierke and Grießhammer published their work in which they were able to ultrasonically atomize metal with melting points up to 700 °C{{Cite journal |last1=Lierke |first1=E.G. |last2=Grießhammer |first2=G. |date=October 1967 |title=The formation of metal powders by ultrasonic atomization of molten metals |url=https://linkinghub.elsevier.com/retrieve/pii/0041624X67900662 |journal=Ultrasonics |language=en |volume=5 |issue=4 |pages=224–228 |doi=10.1016/0041-624X(67)90066-2|url-access=subscription }}.File:Ultrasonic atomizer - recent.png metal ultrasonic atomizer{{Cite web |title=rePOWDER - Ultrasonic Powder Atomizer {{!}} AMAZEMET |url=https://www.amazemet.com/repowder-configurator/ |access-date=2024-11-03 |website=AMAZEMET {{!}} Freedom In Metal Additive Manufacturing |language=en-US}}]]

In 2017 Żrodowski received a Ministry of Science and Higher Education grant named "Diamentowy grant{{Cite web |title=Diamentowe Granty dla studentów Politechniki Warszawskiej / Studenci Doktoranci Absolwenci / Biuletyn PW - Biuletyn PW |url=https://excellence.pw.edu.pl/biuletyn/Studenci-Doktoranci-Absolwenci/Diamentowe-Granty-dla-studentow-Politechniki-Warszawskiej |access-date=2024-11-03 |website=excellence.pw.edu.pl}}" during which he studied laser powder bed fusion of zirconium-based bulk metallic glasses.{{Cite journal |last1=Żrodowski |first1=Łukasz |last2=Wróblewski |first2=Rafał |last3=Leonowicz |first3=Marcin |last4=Morończyk |first4=Bartosz |last5=Choma |first5=Tomasz |last6=Ciftci |first6=Jakub |last7=Święszkowski |first7=Wojciech |last8=Dobkowska |first8=Anna |last9=Ura-Bińczyk |first9=Ewa |last10=Błyskun |first10=Piotr |last11=Jaroszewicz |first11=Jakub |last12=Krawczyńska |first12=Agnieszka |last13=Kulikowski |first13=Krzysztof |last14=Wysocki |first14=Bartłomiej |last15=Cetner |first15=Tomasz |date=2023-08-25 |title=How to control the crystallization of metallic glasses during laser powder bed fusion? Towards part-specific 3D printing of in situ composites |journal=Additive Manufacturing |volume=76 |pages=103775 |doi=10.1016/j.addma.2023.103775 |issn=2214-8604|doi-access=free }} This has resulted in the research and development of ultrasonic atomization of metals for additive manufacturing{{Cite journal |last1=Żrodowski |first1=Łukasz |last2=Wróblewski |first2=Rafał |last3=Choma |first3=Tomasz |last4=Morończyk |first4=Bartosz |last5=Ostrysz |first5=Mateusz |last6=Leonowicz |first6=Marcin |last7=Łacisz |first7=Wojciech |last8=Błyskun |first8=Piotr |last9=Wróbel |first9=Jan S. |last10=Cieślak |first10=Grzegorz |last11=Wysocki |first11=Bartłomiej |last12=Żrodowski |first12=Cezary |last13=Pomian |first13=Karolina |date=January 2021 |title=Novel Cold Crucible Ultrasonic Atomization Powder Production Method for 3D Printing |journal=Materials |language=en |volume=14 |issue=10 |pages=2541 |doi=10.3390/ma14102541 |doi-access=free |issn=1996-1944 |pmc=8153640 |pmid=34068424|bibcode=2021Mate...14.2541Z }} at Warsaw University of Technology and establishing the spin-off company Amazamet.{{Cite web |title=Spin-OFF of Warsaw University of Technology - Amazemet |url=https://ibs.pw.edu.pl/Spolki-SPIN-OFF/AMAZEMET}}{{Cite web |title=AMAZEMET {{!}} Freedom In Metal Additive Manufacturing |url=https://www.amazemet.com/ |access-date=2024-11-12 |website=AMAZEMET {{!}} Freedom In Metal Additive Manufacturing |language=en-US}} In 2024 a joint article lead by Dmitry Eskin and Iakovos Tzanakis in which new insights into the mechanism of ultrasonic atomization were described stating that the cavitation during the process plays a critical role in the ultrasonic atomization which was also filmed for the first time using high-speed imaging{{Cite journal |last1=Priyadarshi |first1=Abhinav |last2=Bin Shahrani |first2=Shazamin |last3=Choma |first3=Tomasz |last4=Zrodowski |first4=Lukasz |last5=Qin |first5=Ling |last6=Leung |first6=Chu Lun Alex |last7=Clark |first7=Samuel J. |last8=Fezzaa |first8=Kamel |last9=Mi |first9=Jiawei |last10=Lee |first10=Peter D. |last11=Eskin |first11=Dmitry |last12=Tzanakis |first12=Iakovos |date=2024-03-05 |title=New insights into the mechanism of ultrasonic atomization for the production of metal powders in additive manufacturing |url=https://linkinghub.elsevier.com/retrieve/pii/S2214860424000794 |journal=Additive Manufacturing |volume=83 |pages=104033 |doi=10.1016/j.addma.2024.104033 |issn=2214-8604}}{{Cite web |last=admin |date=2022-08-10 |title=Ultrasonic atomization principle - AMAZEMET |url=https://www.amazemet.com/ultrasonic-atomization-principle/ |access-date=2024-11-12 |website=AMAZEMET {{!}} Freedom In Metal Additive Manufacturing |language=en-US}}.The sonotrode used in the experiments was made of high-temperature resistant carbon fiber plate to atomize pure aluminum melted at a temperature of 800°C. The ultrasonic atomizer was also used to atomize magnesium alloy,{{Cite journal |last1=Dobkowska |first1=Anna |last2=Żrodowski |first2=Łukasz |last3=Chlewicka |first3=Monika |last4=Koralnik |first4=Milena |last5=Adamczyk-Cieślak |first5=Bogusława |last6=Ciftci |first6=Jakub |last7=Morończyk |first7=Bartosz |last8=Kruszewski |first8=Mirosław |last9=Jaroszewicz |first9=Jakub |last10=Kuc |first10=Dariusz |last11=Święszkowski |first11=Wojciech |last12=Mizera |first12=Jarosław |date=2022-12-01 |title=A comparison of the microstructure-dependent corrosion of dual-structured Mg-Li alloys fabricated by powder consolidation methods: Laser powder bed fusion vs pulse plasma sintering |journal=Journal of Magnesium and Alloys |volume=10 |issue=12 |pages=3553–3564 |doi=10.1016/j.jma.2022.06.003 |issn=2213-9567|doi-access=free }} and metals with melting over 1500°C such as zirconium alloy, titanium alloy{{Cite journal |last1=Schönrath |first1=Hanna |last2=Wegner |first2=Jan |last3=Frey |first3=Maximilian |last4=Schroer |first4=Martin A. |last5=Jin |first5=Xueze |last6=Pérez-Prado |first6=María Teresa |last7=Busch |first7=Ralf |last8=Kleszczynski |first8=Stefan |date=2024-06-01 |title=Novel titanium-based sulfur-containing BMG for PBF-LB/M |journal=Progress in Additive Manufacturing |language=en |volume=9 |issue=3 |pages=601–612 |doi=10.1007/s40964-024-00668-z |issn=2363-9520|doi-access=free }} and high-entropy alloy.{{Cite journal |last1=Zavdoveev |first1=Anatoliy |last2=Zrodowski |first2=Łukasz |last3=Vedel |first3=Dmytro |last4=Cortes |first4=Pedro |last5=Choma |first5=Tomasz |last6=Ostrysz |first6=Mateusz |last7=Stasiuk |first7=Oleksandr |last8=Baudin |first8=Thierry |last9=Klapatyuk |first9=Andrey |last10=Gaivoronskiy |first10=Aleksandr |last11=Bevz |first11=Vitaliy |last12=Pashinska |first12=Elena |last13=Skoryk |first13=Mykola |date=2024-05-15 |title=Atomization of the Fe-rich MnNiCoCr high-entropy alloy for spherical powder production |url=https://linkinghub.elsevier.com/retrieve/pii/S0167577X24003781 |journal=Materials Letters |volume=363 |pages=136240 |doi=10.1016/j.matlet.2024.136240 |bibcode=2024MatL..36336240Z |issn=0167-577X|url-access=subscription }}

• Mist
• Ultrasound
• Piezoelectricity
• Metal powder
• Induction plasma

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Category:Ultrasound