scholarly journals Improving Compactness of 3D Metallic Microstructures Printed by Laser-Induced Forward Transfer

Crystals ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 291
Author(s):  
Niv Gorodesky ◽  
Sharona Sedghani-Cohen ◽  
Ofer Fogel ◽  
Amir Silber ◽  
Maria Tkachev ◽  
...  
Keyword(s):  
Material Properties ◽  
Single Step ◽  
Digital Printing ◽  
Ambient Conditions ◽  
Chemical Corrosion ◽  
Metal Structures ◽  
Specific Choice ◽  
Complex Shapes ◽  
Forward Transfer ◽  
Printing Method

Laser-induced forward transfer (LIFT) has been shown to be a useful technique for the manufacturing of micron-scale metal structures. LIFT is a high-resolution, non-contact digital printing method that can support the fabrication of complex shapes and multi-material structures in a single step under ambient conditions. However, LIFT printed metal structures often suffer from inferior mechanical, electrical, and thermal properties when compared to their bulk metal counterparts, and often are prone to enhanced chemical corrosion. This is due mostly to their non-compact structures, which have voids and inter-droplet delamination. In this paper, a theoretical framework together with experimental results of achievable compactness limits is presented for a variety of metals. It is demonstrated that compactness limits depend on material properties and jetting conditions. It is also shown how a specific choice of materials can yield compact structures, for example, when special alloys are chosen along with a suitable donor construct. The example of printed amorphous ZrPd is detailed. This study contributes to a better understanding of the limits of implementing LIFT for the fabrication of metal structures, and how to possibly overcome some of these limitations.

scholarly journals Synthesis of Nanotips Through Femtosecond Laser Ablation of Glass with Assisted Gas

2021 ◽  
Author(s):  
Nikunj Patel
Keyword(s):  
Femtosecond Laser ◽  
Building Materials ◽  
High Vacuum ◽  
Synthesis Method ◽  
Femtosecond Laser Ablation ◽  
Target Surface ◽  
Laser Pulses ◽  
Single Step ◽  
Femtosecond Laser Irradiation ◽  
Ambient Conditions

Nanotips are the key nanostructures for many applications. Until now, the nanotips of only the crystalline materials have been produced via various deposition methods which require sophisticated equipment, high vacuum, and clean room operations. This thesis proposes a single step, rapid synthesis method using femtosecond laser irradiation at megahertz frequency with background flow of nitrogen gas at ambient conditions. Amorphous nanotips are obtained without the use of catalyst. The nanotips grow from highly energetic plasma generated when target is irradiated with laser pulses. The vapor condensates, nanoparticles and droplets from the plasma get deposited back on to the hot target surface where they experience force imbalance due to which the stems for the nanotips growth are initiated. Once the stems are generated, the continuous deposition of vapor condensates [sic] provides building materials to the stems to complete the growth of nanotips. Further study found that the growth of the nanotips is influenced by laser parameters and gas conditions.

scholarly journals Digital printing of shape-morphing natural materials

2021 ◽  
Vol 118 (43) ◽  
pp. e2113715118
Author(s):  
Ze Zhao ◽  
Jatin Kumar ◽  
Youngkyu Hwang ◽  
Jingyu Deng ◽  
Mohammed Shahrudin Bin Ibrahim ◽  
...  
Keyword(s):  
Wide Spectrum ◽  
Substrate Material ◽  
Digital Printing ◽  
Shape Evolution ◽  
The Finite Element Method ◽  
Computational Simulations ◽  
Natural Materials ◽  
Shape Morphing ◽  
Geometrical Features ◽  
Complex Shapes

We demonstrate how programmable shape evolution and deformation can be induced in plant-based natural materials through standard digital printing technologies. With nonallergenic pollen paper as the substrate material, we show how specific geometrical features and architectures can be custom designed through digital printing of patterns to modulate hygrophobicity, geometry, and complex shapes. These autonomously hygromorphing configurations can be “frozen” by postprocessing coatings to meet the needs of a wide spectrum of uses and applications. Through computational simulations involving the finite element method and accompanying experiments, we develop quantitative insights and a general framework for creating complex shapes in eco-friendly natural materials with potential sustainable applications for scalable manufacturing.

scholarly journals Overlapping Limitations for ps-Pulsed LIFT Printing of High Viscosity Metallic Pastes

Metals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 168 ◽  
Author(s):  
David Munoz-Martin ◽  
Yu Chen ◽  
Miguel Morales ◽  
Carlos Molpeceres
Keyword(s):  
Laser Pulse ◽  
Short Distance ◽  
Laser Pulse Energy ◽  
Laser Pulses ◽  
High Viscosity ◽  
Single Step ◽  
High Speeds ◽  
Forward Transfer ◽  
Micron Size ◽  
Interference Problems

Laser-induced forward transfer (LIFT) technique has been used for printing a high viscosity (250 Pa·s) commercial silver paste with micron-size particles (1–4 µm). Volumetric pixels (voxels) transferred using single ps laser pulses are overlapped in order to obtain continuous metallic lines. However, interference problems between successive voxels is a major issue that must be solved before obtaining lines with good morphologies. The effects of the laser pulse energy, thickness of the donor paste film, and distance between successive voxels on the morphology of single voxels and lines are discussed. Due to the high viscosity of the paste, the void in the donor film after a printing event remains, and it negatively affects the physical transfer mechanism of the next laser pulses. When two laser pulses are fired at a short distance, there is no transfer at all. Only when the pulses are separated by a distance long enough to avoid interference but short enough to allow overlapping (≈100 µm), is it possible to print continuous lines in a single step. Finally, the knowledge obtained has allowed the printing of silver lines at high speeds (up to 60 m/s).

Single step high-speed printing of continuous silver lines by laser-induced forward transfer

2016 ◽  
Vol 374 ◽  
pp. 183-189 ◽  
Author(s):  
D. Puerto ◽  
E. Biver ◽  
A.-P. Alloncle ◽  
Ph. Delaporte
Keyword(s):  
High Speed ◽  
Single Step ◽  
Forward Transfer

Laser forward transfer using a sacrificial layer: Influence of the material properties

2007 ◽  
Vol 254 (4) ◽  
pp. 1322-1326 ◽  
Author(s):  
Romain Fardel ◽  
Matthias Nagel ◽  
Frank Nüesch ◽  
Thomas Lippert ◽  
Alexander Wokaun
Keyword(s):  
Material Properties ◽  
Sacrificial Layer ◽  
Forward Transfer

scholarly journals Single-step fabrication of microfluidic channels filled with nanofibrous membrane using femtosecond laser irradiation

2021 ◽  
Author(s):  
Amirhossein Tavangar ◽  
Bo Tan ◽  
Krishnan Venkatakrishnan
Keyword(s):  
Femtosecond Laser ◽  
Laser Irradiation ◽  
Microfluidic Channel ◽  
Scanning Speed ◽  
Single Step ◽  
Femtosecond Laser Irradiation ◽  
Microfluidic Channels ◽  
Ambient Conditions ◽  
Nanofibrous Structure ◽  
Channel Surface

In this paper, we demonstrate a new method of fabricating silicon microfluidic channels filled with a porous nanofibrous structure utilizing a femtosecond laser. The nanofibrous structure can act as a membrane used for microfiltration. This method allows us to generate both the microfluidic channel and the fibrous nanostructure in a single step under ambient conditions. Due to laser irradiation, a large number of nanoparticles ablate from the channel surface, and then aggregate and grow into porous nanofibrous structures and fill the channels. Energy dispersive x-ray spectroscopy (EDS) analysis was conducted to examine the oxygen concentration in the membrane structure. Our results demonstrated that by controlling the laser parameters including pulse repetition, pulse width and scanning speed, different microfluidic channels with a variety of porosity could be obtained.

Sign in / Sign up

Export Citation Format

Share Document