Raw Particle Aggregation Control for Fabricating Submicrometer-sized Spherical Particles by Pulsed-laser Melting in Liquid

2013 ◽  
Vol 42 (5) ◽  
pp. 530-531 ◽  
Author(s):  
Yoshie Ishikawa ◽  
Yukiko Katou ◽  
Naoto Koshizaki ◽  
Qi Feng
Keyword(s):  
Pulsed Laser ◽  
Particle Aggregation ◽  
Spherical Particles ◽  
Laser Melting ◽  
Aggregation Control

scholarly journals Determining the Composite Structure of Au-Fe-Based Submicrometre Spherical Particles Fabricated by Pulsed-Laser Melting in Liquid

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 198 ◽  
Author(s):  
Hokuto Fuse ◽  
Naoto Koshizaki ◽  
Yoshie Ishikawa ◽  
Zaneta Swiatkowska-Warkocka
Keyword(s):  
Formation Mechanism ◽  
Extreme Temperature ◽  
Pulsed Laser ◽  
Spherical Particles ◽  
Laser Melting ◽  
Quenching Rate ◽  
Two Measures ◽  
Shell Particles ◽  
Aggregation Control

Submicrometre spherical particles made of Au and Fe can be fabricated by pulsed-laser melting in liquid (PLML) using a mixture of Au and iron oxide nanoparticles as the raw particles dispersed in ethanol, although the detailed formation mechanism has not yet been clarified. Using a 355 nm pulsed laser to avoid extreme temperature difference between two different raw particles during laser irradiation and an Fe2O3 raw nanoparticle colloidal solution as an iron source to promote the aggregation of Au and Fe2O3 nanoparticles, we performed intensive characterization of the products and clarified the formation mechanism of Au-Fe composite submicrometre spherical particles. Because of the above two measures (Fe2O3 raw nanoparticle and 355 nm pulsed laser), the products—whether the particles are phase-separated or homogeneous alloys—basically follow the phase diagram. In Fe-rich range, the phase-separated Au-core/Fe-shell particles were formed, because quenching induces an earlier solidification of the Fe-rich component as a result of cooling from the surrounding ethanol. If the particle size is small, the quenching rate becomes very rapid and particles were less phase-separated. For high Au contents exceeding 70% in weight, crystalline Au-rich alloys were formed without phase separation. Thus, this aggregation control is required to selectively form homogeneous or phase-separated larger submicrometre-sized particles by PLML.

scholarly journals Influence of pulse frequency on synthesis of nano and submicrometer spherical particles by pulsed laser melting in liquid

2018 ◽  
Vol 435 ◽  
pp. 529-534 ◽  
Author(s):  
Shota Sakaki ◽  
Hiroshi Ikenoue ◽  
Takeshi Tsuji ◽  
Yoshie Ishikawa ◽  
Naoto Koshizaki
Keyword(s):  
Pulsed Laser ◽  
Pulse Frequency ◽  
Spherical Particles ◽  
Laser Melting

Automated iterative batch processing of submicrometer spherical particles by pulsed laser melting in liquid

2020 ◽  
Vol 219 ◽  
pp. 115580
Author(s):  
Ryosuke Takai ◽  
Naoto Koshizaki ◽  
Yoshie Ishikawa ◽  
Yukiya Hakuta
Keyword(s):  
Pulsed Laser ◽  
Batch Processing ◽  
Spherical Particles ◽  
Laser Melting

High-Strength Sub-Micrometer Spherical Particles Fabricated by Pulsed Laser Melting in Liquid

2018 ◽  
Vol 35 (7) ◽  
pp. 1800061 ◽  
Author(s):  
Mitsuhiko Kondo ◽  
Nobuyuki Shishido ◽  
Shoji Kamiya ◽  
Atsushi Kubo ◽  
Yoshitaka Umeno ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
High Strength ◽  
Spherical Particles ◽  
Laser Melting

scholarly journals Comparison of picosecond and nanosecond lasers for the synthesis of TiN sub-micrometer spherical particles by pulsed laser melting in liquid

2018 ◽  
Vol 11 (3) ◽  
pp. 035001 ◽  
Author(s):  
Shota Sakaki ◽  
Ken-ichi Saitow ◽  
Masanori Sakamoto ◽  
Hiroyuki Wada ◽  
Zaneta Swiatkowska-Warkocka ◽  
...  
Keyword(s):  
Pulsed Laser ◽  
Spherical Particles ◽  
Laser Melting ◽  
Nanosecond Lasers

scholarly journals Fracture and Embedment Behavior of Brittle Submicrometer Spherical Particles Fabricated by Pulsed Laser Melting in Liquid Using a Scanning Electron Microscope Nanoindenter

Nanomaterials ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 2201
Author(s):  
Daizen Nakamura ◽  
Naoto Koshizaki ◽  
Nobuyuki Shishido ◽  
Shoji Kamiya ◽  
Yoshie Ishikawa
Keyword(s):  
Electron Microscope ◽  
Scanning Electron Microscope ◽  
Density Functional ◽  
Bending Strength ◽  
Pulsed Laser ◽  
Spherical Shape ◽  
Spherical Particles ◽  
Laser Melting ◽  
Load Displacement ◽  
Scanning Electron

Generally, hard ceramic carbide particles, such as B4C and TiC, are angulated, and particle size control below the micrometer scale is difficult owing to their hardness. However, submicrometer particles (SMPs) with spherical shape can be experimentally fabricated, even for hard carbides, via instantaneous pulsed laser heating of raw particles dispersed in a liquid (pulsed laser melting in liquid). The spherical shape of the particles is important for mechanical applications as it can directly transfer the mechanical force without any loss from one side to the other. To evaluate the potential of such particles for mechanical applications, SMPs were compressed on various substrates using a diamond tip in a scanning electron microscope. The mechanical behaviors of SMPs were then examined from the obtained load–displacement curves. Particles were fractured on hard substrates, such as SiC, and fracture strength was estimated to be in the GPa range, which is larger than their corresponding bulk bending strength and is 10–40% of their ideal strength, as calculated using the density-functional theory. Contrarily, particles can be embedded into soft substrates, such as Si and Al, and the local hardness of the substrate can be estimated from the load–displacement curves as a nanoscale Brinell hardness measurement.

Sign in / Sign up

Export Citation Format

Share Document