Effect of external static magnetic field on the particle distribution, the metallurgical process and the microhardness of Sn3.5Ag solder with magnetic Ni particles

Purpose This paper aims to investigate the mechanism of Ni particles distribution in the liquid Sn3.5Ag melt under the external static magnetic field. The control steps of Ni particles and the Sn3.5Ag melt metallurgical process were studied. After aging, the microhardness of pure Sn3.5Ag, Sn3.5Ag containing randomly distributed Ni particles and Sn3.5Ag containing columnar Ni particles were compared. Design/methodology/approach Place the sample in a crucible for heating. After the sample melts, place a magnet directly above and below the sample to provide a magnetic field. Sn3.5Ag with the different morphological distribution of Ni particles was obtained by holding for different times under different magnetic field intensities. Finally, pure Sn3.5Ag, Sn3.5Ag with random distributed Ni particles and Sn3.5Ag with columnar Ni particles were aged and their microhardness was tested after aging. Findings The experimental results show that with the increase of magnetic field strength, the time for Ni particle distribution in Sn3.5Ag melt to reach equilibrium is shortened. After aging, the microhardness of Sn3.5Ag containing columnar nickel particles is higher than that of pure Sn3.5Ag and Sn3.5Ag containing randomly distributed nickel particles. A chemical reaction is the control step in the metallurgical process of nickel particles and molten Sn3.5Ag. Originality/value Under the action of the magnetic field, Ni particles in Sn3.5Ag melt will be arranged into columns. With the increase of magnetic field strength, the shorter the time for Ni particles in Sn3.5Ag melt to arrange in a column. With the extension of the service time of the solder joint, if Sn3.5Ag with columnar nickel particles is used as the solder joint material, its microhardness is better than Sn3.5Ag with arbitrarily distributed nickel particles and pure Sn3.5Ag.

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Relationship between Applied Static Magnetic Field Strength and Thermal Conductivity Values of Molten Materials Measured Using the EML Technique

JOURNAL OF CHEMICAL ENGINEERING OF JAPAN ◽

10.1252/jcej.11we035 ◽

2011 ◽

Vol 44 (5) ◽

pp. 321-327 ◽

Cited By ~ 10

Author(s):

Yuya Baba ◽

Ken-ichi Sugioka ◽

Masaki Kubo ◽

Takao Tsukada ◽

Kazutoshi Sugie ◽

...

Keyword(s):

Magnetic Field ◽

Thermal Conductivity ◽

Field Strength ◽

Magnetic Field Strength ◽

Static Magnetic Field ◽

Molten Materials

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Polarized Induced Magnetic Broadening of Photonic Activities in Fe3O4-Elastomer Composites

MRS Proceedings ◽

10.1557/opl.2013.539 ◽

2013 ◽

Vol 1509 ◽

Author(s):

Danhao Ma ◽

Dustin T. Hess ◽

Pralav P Shetty ◽

Kofi W. Adu ◽

Richard Bell ◽

...

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Magnetic Field Strength ◽

Static Magnetic Field ◽

Electric Dipole ◽

Composite Films ◽

Optical Response ◽

Silicone Elastomer ◽

Magnetic Field Effects ◽

Out Of Plane

AbstractWe report a systematic study of polarization and magnetic field effects on the optical response of Fe3O4-silicone elastomer composite. The Fe3O4 particles were aligned in a silicone elastomer matrix with an external static magnetic field. Films of composites containing 5wt% of 20nm ≤ d ≤ 30nm Fe3O4 particles aligned in- and out-of-plane in the elastomer host were prepared. The optical spectra of the films were measured with the Perkin-Elmer Lambda 950 UV/vis/NIR spectrometer. We observed a systematic redshift in the optical response of the outof-plane composite films with increasing static magnetic field strength, which saturated near 600 Gauss. We obtained a maximum redshift of ∼46 nm at 600 Gauss. The observed redshift in the optical response of the out-of-plane composite film is attributed to the effect of the magnetic field. This facilitated the formation of the highly aligned particles that induced strong electric dipole in the aligned particles. Interestingly, there were no observable shifts with increasing magnetic field strength in the in-plane films, suggesting that the orientation (polarization) of the magnetic dipole and the induced electric dipole play a crucial role in the optical response.

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416. Concentration of Gd-DTPA and signal intensity; effect of static magnetic field strength

Japanese Journal of Radiological Technology ◽

10.6009/jjrt.kj00003322538 ◽

1990 ◽

Vol 46 (8) ◽

pp. 1387

Author(s):

Masayuki Nakasuji ◽

Kazutoshi Katakami ◽

Takao Kawano ◽

Kouichi Arita ◽

Tetsuo Yama ◽

...

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Magnetic Field Strength ◽

Static Magnetic Field ◽

Signal Intensity ◽

Intensity Effect

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Quantifying the Benefit of a Dedicated “Magnetoskeleton” in Bacterial Magnetotaxis by Live-Cell Motility Tracking and Soft Agar Swimming Assay

Applied and Environmental Microbiology ◽

10.1128/aem.01976-19 ◽

2019 ◽

Vol 86 (3) ◽

Cited By ~ 2

Author(s):

Daniel Pfeiffer ◽

Dirk Schüler

Keyword(s):

Magnetic Field ◽

Magnetic Fields ◽

Field Strength ◽

Cell Motility ◽

Magnetic Field Strength ◽

Geomagnetic Field ◽

Soft Agar ◽

Content Type ◽

Magnetospirillum Gryphiswaldense ◽

Weak Magnetic Fields

ABSTRACT The alphaproteobacterium Magnetospirillum gryphiswaldense has the intriguing ability to navigate within magnetic fields, a behavior named magnetotaxis, governed by the formation of magnetosomes, intracellular membrane-enveloped crystals of magnetite. Magnetosomes are aligned in chains along the cell’s motility axis by a dedicated multipart cytoskeleton (“magnetoskeleton”); however, precise estimates of its significance for magnetotaxis have not been reported. Here, we estimated the alignment of strains deficient in various magnetoskeletal constituents by live-cell motility tracking within defined magnetic fields ranging from 50 μT (reflecting the geomagnetic field) up to 400 μT. Motility tracking revealed that ΔmamY and ΔmamK strains (which assemble mispositioned and fragmented chains, respectively) are partially impaired in magnetotaxis, with approximately equal contributions of both proteins. This impairment was reflected by a required magnetic field strength of 200 μT to achieve a similar degree of alignment as for the wild-type strain in a 50-μT magnetic field. In contrast, the ΔmamJ strain, which predominantly forms clusters of magnetosomes, was only weakly aligned under any of the tested field conditions and could barely be distinguished from a nonmagnetic mutant. Most findings were corroborated by a soft agar swimming assay to analyze magnetotaxis based on the degree of distortion of swim halos formed in magnetic fields. Motility tracking further revealed that swimming speeds of M. gryphiswaldense are highest within the field strength equaling the geomagnetic field. In conclusion, magnetic properties and intracellular positioning of magnetosomes by a dedicated magnetoskeleton are required and optimized for bacterial magnetotaxis and most efficient locomotion within the geomagnetic field. IMPORTANCE In Magnetospirillum gryphiswaldense, magnetosomes are aligned in quasi-linear chains in a helical cell by a complex cytoskeletal network, including the actin-like MamK and adapter MamJ for magnetosome chain concatenation and segregation and MamY to position magnetosome chains along the shortest cellular axis of motility. Magnetosome chain positioning is assumed to be required for efficient magnetic navigation; however, the significance and contribution of all key constituents have not been quantified within defined and weak magnetic fields reflecting the geomagnetic field. Employing two different motility-based methods to consider the flagellum-mediated propulsion of cells, we depict individual benefits of all magnetoskeletal constituents for magnetotaxis. Whereas lack of mamJ resulted almost in an inability to align cells in weak magnetic fields, an approximately 4-fold-increased magnetic field strength was required to compensate for the loss of mamK or mamY. In summary, the magnetoskeleton and optimal positioning of magnetosome chains are required for efficient magnetotaxis.

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Stress measurement based on magnetostrictive characteristic parameters

Insight - Non-Destructive Testing and Condition Monitoring ◽

10.1784/insi.2021.63.5.283 ◽

2021 ◽

Vol 63 (5) ◽

pp. 283-288

Author(s):

Entao Yao ◽

Fei Han ◽

Ping Wang ◽

Yuan Zhang

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Magnetic Field Strength ◽

Static Magnetic Field ◽

Stress Measurement ◽

Maximum Relative Error ◽

Electromagnetic Acoustic Transducer ◽

Wide Range ◽

The Relationship ◽

Non Destructive

Non-destructive testing (NDT) involving stress measurement has found a wide range of applications in rail, pipeline, bridge and other engineering areas and it is therefore necessary to find a method to measure stress. In this paper, a non-destructive method is proposed to measure stress by observation of the magnetostrictive properties of the objects. Stress in the elastic range is applied to the ferromagnetic material, changing its lattice, while stress in the plastic range changes its microstructure. These are the reasons for the magnetostrictive coefficient variation of the material. An experimental platform was set up, using a cantilever beam with a strain gauge, to study the relationship between the SH wave, the static magnetic field strength and the applied uniaxial stress. The curve obtained shows the relationship between the amplitude of the electromagnetic acoustic transducer (EMAT) signal and the static magnetic field strength. The magnetostrictive parameters, sensitive to stress, were extracted from the curve. This method is verified through trials on test samples with a maximum relative error between experimental and predicted values of 8.06%.

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