Effect of bismuth–tin alloy particle diameter on bonding strength of copper nanoparticles/bismuth–tin solder hybrid joints

Abstract Ni nanoparticles were successfully used to join Inconel 718 via transient liquid phase (TLP) bonding in a vacuum environment. Ni nanoparticles of 20 nm, 29 nm, and 41 nm in diameter were synthesized by controlling the reducing agent injection rate and joined at up to 1050 °C and heating rate 5–15 °C/min. Based on the Gibbs-Thomson equation and surface melting models, joining using Ni nanoparticles occurs due to competing solid-state sintering and surface melting processes. It was found that faster heating rate; higher maximum bonding temperature, and larger particle size resulted in higher bonding strength. Using a faster heating rate suppresses the amount of solid-state particle-particle sintering that occurs at lower temperatures, where particle-Inconel 718 joining is less active. The suppression of particle-particle sintering as a function of particle diameter is also discussed. The maximum bonding strength achieved is 243 MPa. The fracture surface for Ni nanoparticle-bonded joints demonstrated intergranular fracture (low strength joints) and a combination of cleavage and microvoid coalescence (high strength joints).

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Synthesized copper nanoparticles by sonoelectrodeposition for gas filter applications

Iraqi Journal of Physics (IJP) ◽

10.30723/ijp.v16i38.15 ◽

2018 ◽

Vol 16 (38) ◽

pp. 132-138

Author(s):

Ahmed Q. Abdullah

Keyword(s):

Copper Nanoparticles ◽

Current Density ◽

Particle Diameter ◽

X Ray Diffraction ◽

Good Efficiency ◽

Power Ultrasound ◽

X Ray ◽

High Power Ultrasound ◽

Different Diameters ◽

Solution Acidity

Copper nanoparticles (CuNPs) were prepared with different diameters by sonoelectrodeposition technique using Electrodeposition process coupled with high-power ultrasound horn (Sonoelectrodeposition). The particle diameter of the CuNPs was adjusted by varying CuSO4 solution acidity (pH) and current density. The morphology and structure of the CuNPs were examined by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). It was found that the size of the produced copper nanoparticles ranged between 22 to 77 nm, where the diameter of CuNPs increases with reduction the solution acidity from 0.5 to 1.5 pH and increasing the current density of the deposition from 100 to 400 nm. Finally the produced CuNPs were pressed to fabricate disc filter and then the permeability, porosity, and filtration efficiency were determined which showed good efficiency.

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Surface Structure of Nucleated Animal Cells: Carbon Replicas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100060611 ◽

1967 ◽

Vol 25 ◽

pp. 120-121

Author(s):

Robert M. Glaeser ◽

Thea B. Scott

Keyword(s):

Cell Surface ◽

Surface Structure ◽

Particle Diameter ◽

Cellular Functions ◽

Animal Cells ◽

Replica Technique ◽

Carbon Replica ◽

Characteristic Particle ◽

Cell Surface Structure ◽

Carbon Replicas

The carbon-replica technique can be used to obtain information about cell-surface structure that cannot ordinarily be obtained by thin-section techniques. Mammalian erythrocytes have been studied by the replica technique and they appear to be characterized by a pebbly or “plaqued“ surface texture. The characteristic “particle” diameter is about 200 Å to 400 Å. We have now extended our observations on cell-surface structure to chicken and frog erythrocytes, which possess a broad range of cellular functions, and to normal rat lymphocytes and mouse ascites tumor cells, which are capable of cell division. In these experiments fresh cells were washed in Eagle's Minimum Essential Medium Salt Solution (for suspension cultures) and one volume of a 10% cell suspension was added to one volume of 2% OsO4 or 5% gluteraldehyde in 0.067 M phosphate buffer, pH 7.3. Carbon replicas were obtained by a technique similar to that employed by Glaeser et al. Figure 1 shows an electron micrograph of a carbon replica made from a chicken erythrocyte, and Figure 2 shows an enlarged portion of the same cell.

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AEM analysis of solidification catalysts in atomized Fe-Ni

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100144395 ◽

1986 ◽

Vol 44 ◽

pp. 584-585

Author(s):

Matthew R. Libera

Keyword(s):

Powder Particle ◽

Alloy Composition ◽

Particle Diameter ◽

Metastable Phases ◽

Liquid Droplets ◽

Nucleation Kinetics ◽

Ni Alloys ◽

Nonequilibrium Solidification

The liquid droplets produced by atomization processes are believed to undergo substantial supercooling during solidification, because the catalytic heterogeneities, for statistical reasons, tend to be isolated in the larger droplets. This supercooling can lead to the nucleation of metastable phases. As part of a study on the effect of liquid supercooling on nonequilibrium solidification, three binary Fe-Ni alloys have been produced by conventional argon atomization (Fe-20Ni, Fe-30Ni, and Fe-40Ni). The primary variables in these experiments are: i) the alloy composition; and ii) the powder particle diameter (inversely proportional to supercooling). Of particular interest in this system is the competitive nucleation kinetics between the stable fee and metastable bec phases. Bcc is expected to nucleate preferentially with decreasing %Ni and decreasing particle diameter.

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Effect of ink and paperboard characteristics on flexographic print quality based on print density

TAPPI Journal ◽

10.32964/tj10.9.7 ◽

2011 ◽

Vol 10 (9) ◽

pp. 7-13

Author(s):

KHODADAD MALMIRCHEGINI ◽

FARSHAD SARKHOSH RAHMANI

Keyword(s):

Water Absorption ◽

Significant Influence ◽

Particle Diameter ◽

Print Quality ◽

Printing Technology ◽

Plastic Films ◽

Printing Inks ◽

Packaging Industry ◽

Solids Content ◽

Density Results

Flexography is an evolving printing technology that is suitable for printing on coated and uncoated paperboard and board, nonporous substrates including metalized and paperboard foils, and plastic films used especially in the packaging industry. This study evaluated the effect of paperboard and ink characteristics on flexographic print density in paperboard. Three commercial paperboards from different companies were prepared: brown kraft from Thailand, white kraft from Spain, and test liner from Iran. Four samples of process print inks from Iran were used in this investigation. Paperboard properties, such as roughness and water absorption, and ink characteristics, including solids content, PH and particle diameter, were measured. The inks were printed on paperboards using a roll no.15 applicator with a blade metering device, and the print densities were measured. Results showed that solids content, pH, and particle diameter of printing inks influenced print density, while the roughness and water absorption of the three types of paperboard had no significant influence on print density. Results also illustrated that two levels of ink viscosity (25–30 and 50–55 mPa·s) were insignificant to print density.

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