Phase Transformations Induced in Metallic Glasses by Pulsed Laser and Alpha Particle Beam Irradiation

1998 ◽  
Vol 540 ◽  
Author(s):  
M. Sorescu
Keyword(s):  
Metallic Glass ◽  
Alpha Particle ◽  
Magnetic Moment ◽  
Ac Susceptibility ◽  
Amorphous Material ◽  
Pulsed Laser ◽  
Hysteresis Loops ◽  
Particle Beam ◽  
Beam Irradiation ◽  
Saturation Magnetic Moment

AbstractNd:YAG laser (λ,=532 nm, τ=8 ns, Φ =30 J/cm2, v=10 Hz) induced transformations in Fe81B135Si35C2metallic glass were characterized by transmission and conversion electron Mossbauer spectroscopy, hysteresis loops and ac susceptibility measurements. The radiation-driven changes were further compared with alpha particle beam irradiation effects (W=2.8 MeV, Φ=1016and 1017 cm−2) in the same amorphous material. Pulsed laser irradiation of Fe81B135Si3.5C2 metallic glass was found to induce magnetic anisotropy, surface oxidation, onset of crystallization, slight increase in the saturation magnetic moment and changes in the imaginary susceptibility component. Alpha particle beam irradiation of Fe81B13.5Si3.5C2 metallic glass caused partial crystallization of the bulk of the specimen, total crystallization of the surface, as well as dose-dependent changes in the saturation magnetic moment, hysteresis and real susceptibility component.

scholarly journals Annealing effects on the magnetic properties of highly-packed vertically-aligned nickel nanotubes

RSC Advances ◽  
2017 ◽  
Vol 7 (30) ◽  
pp. 18609-18616 ◽  
Author(s):  
Vlad-Andrei Antohe ◽  
Emeline Nysten ◽  
Juan Manuel Martínez-Huerta ◽  
Pedro Miguel Pereira de Sá ◽  
Luc Piraux
Keyword(s):  
Magnetic Properties ◽  
Magnetic Moment ◽  
Hysteresis Loops ◽  
Thermal Conversion ◽  
Dense Array ◽  
Saturation Magnetic Moment ◽  
Annealing Effects ◽  
Vertically Aligned

Hysteresis loops showing the decrease of the saturation magnetic moment (left) through a dense array of vertically-aligned Ni nanotubes after their progressive thermal conversion into hybrid ferromagnetic/antiferromagnetic Ni/NiO nanotubes (right).

scholarly journals Devitrification of thin film Cu-Zr metallic glass via ultrashort pulsed laser annealing

2021 ◽  
pp. 161437
Author(s):  
J. Antonowicz ◽  
P. Zalden ◽  
K. Sokolowski-Tinten ◽  
K. Georgarakis ◽  
R. Minikayev ◽  
...  
Keyword(s):  
Thin Film ◽  
Metallic Glass ◽  
Laser Annealing ◽  
Pulsed Laser ◽  
Pulsed Laser Annealing ◽  
Ultrashort Pulsed Laser

Microstructure of Compositionally Graded PZT films Grown by Pulsed Laser Deposition

2008 ◽  
Vol 14 (S3) ◽  
pp. 53-56
Author(s):  
S.A.S. Rodrigues ◽  
A. Khodorov ◽  
M. Pereira ◽  
M.J.M. Gomes
Keyword(s):  
Pulsed Laser Deposition ◽  
Lead Zirconate Titanate ◽  
Film Growth ◽  
Pulsed Laser ◽  
Hysteresis Loops ◽  
Lead Zirconate ◽  
Laser Deposition ◽  
Composition Gradient ◽  
Complex Structures ◽  
Pzt Films

Ferroelectric films with a composition gradient have attracted much attention because of their large polarization offset present in the hysteresis loops. Lead Zirconate Titanate (PZT) films were deposited on Pt/TiO2/SiO2/Si substrates by Pulsed Laser Deposition (PLD) technique, using a Nd:YAG laser (Surelite) with a source pulse wavelength of 1064 nm and duration of 5-7 ns delivering an energy of 320 mJ per pulse and a laser fluence energy about 20 J/cm2. The film growth is performed in O2 atmosphere (0,40 mbar) while the substrate is heated at 600°C by a quartz lamp. Starting from ceramic targets based on PZT compositions and containing 5% mol. of excess of PbO to compensate the lead evaporation during heat treatment, three films with different compositions Zr/Ti 55/45, 65/35 and 92/8, and two types of complex structures were produced. These complex structures are in the case of the up-graded structure (UpG), with PZT (92/8) at the bottom, PZT (65/35) on middle and PZT (55/45) on the top, and for down-graded (DoG) one, that order is reversed.

A HYBRID MODEL ON HYSTERESIS LOOP AND COERCIVITY IN NANOSTRUCTURED PERMANENT MAGNETS

2006 ◽  
Vol 05 (04n05) ◽  
pp. 627-631 ◽  
Author(s):  
M. J. SUN ◽  
G. P. ZHAO ◽  
J. LIANG ◽  
G. ZHOU ◽  
H. S. LIM ◽  
...  
Keyword(s):  
Thin Films ◽  
Domain Wall ◽  
Grain Boundary ◽  
Magnetic Moment ◽  
Permanent Magnets ◽  
Hysteresis Loops ◽  
Bulk Materials ◽  
Rotational Model ◽  
Moment Distribution ◽  
Coercivity Mechanism

A simplified micromagnetic model has been proposed to calculate the hysteresis loops of nanostructured permanent magnets for various configurations, including thin films, exchange-coupled double-layer systems and bulk materials. The reversal part of the hysteresis is based on the Stoner–Wohlfarth coherent rotational model and the coercivity mechanism is due mainly to the motion of the transition region (a domain wall like magnetic moment distribution in the grain boundary). The elements of nucleation and pinning models are also incorporated.

Post-Processing of Pulsed Laser-Deposited Pzt Thin Films

1991 ◽  
Vol 243 ◽  
Author(s):  
C. K. Chiang ◽  
W. Wong-Ng ◽  
L. P. Cook ◽  
P. K. Schenck ◽  
H. M. Lee ◽  
...  
Keyword(s):  
Thin Films ◽  
Amorphous Material ◽  
Ferroelectric Properties ◽  
Pulsed Laser ◽  
Linear Shrinkage ◽  
Laser Deposition ◽  
Amorphous Films ◽  
Pzt Thin Films ◽  
Si Substrates ◽  
Pzt Thin Film

AbstractPZT thin films were prepared by pulsed laser deposition on unheated Ptcoated Si substrates. As deposited, the films were amorphous. Films crystallized at 550 - 600 °C to produce predominantly crystalline ferroelectric PZT. Crystallization of the amorphous material was accompanied by a linear shrinkage of ∼2 %, as manifested in development of cracks in the film. Spacing, width and morphology of larger cracks followed a regular progression with decreasing film thickness. For film thicknesses less than 500 runm, much of the shrinkage was taken up by small, closely-spaced cracks of local extent. Implications for measurement of PZT thin film ferroelectric properties and processing are discussed.

Superconducting Effects in Rapidly Quenched Materials Formed by Ion and Laser Bombardment

1981 ◽  
Vol 4 ◽  
Author(s):  
Bernd Stritzker
Keyword(s):  
Electron Beam ◽  
Low Temperature ◽  
Electron Beam Irradiation ◽  
Pulsed Laser ◽  
Ion Bombardment ◽  
Heavy Ion ◽  
Superconducting Properties ◽  
Beam Irradiation ◽  
Metastable Alloys ◽  
Vapor Quenching

ABSTRACTThe application of low temperature ion bombardment and pulsed laser or electron beam irradiation for the production of rapidly quenched superconducting alloys is described and compared with other more conventionally used non-equilibrium techniques. The comparison is based on the identification of the metastable phases produced by their specific electrical and superconducting properties. It is concluded that low temperature heavy ion bombardment is comparable with vapor quenching whereas laser quenching yields results similar to liquid quenching. Finally, the interesting superconducting properties of these rapidly quenched metastable alloys are discussed.

Ion Beam, Rapid Thermal, and Laser Mixing Phenomena in Insulators

1985 ◽  
Vol 60 ◽  
Author(s):  
J. Narayan ◽  
B.R. Appleton
Keyword(s):  
Free Energy ◽  
Substrate Temperature ◽  
Laser Irradiation ◽  
Rapid Thermal Annealing ◽  
Ion Beam ◽  
Pulsed Laser ◽  
Beam Irradiation ◽  
Ion Beam Irradiation ◽  
Metal Overlayers ◽  
Pulsed Laser Irradiation

AbstractWe have studied mixing of metal overlayers (Ni, Cr, Ti, W, Ta, Zr, Cu) on insulators (SiC, Si3N4, Al2O3, SiO2) after ion beam irradiation, rapid thermal annealing, and pulsed laser irradiation. The nature and amount of mixing varies from stoichiometric to continuous, to ballistic, to no mixing at all. For a given system, the amount of mixing was found to increase with increasing substrate temperature. The enhanced mixing with increasing substrate temperature is correlated with concomitant free energy associated with the reactions. Certain systems such as Cu on Al2O3 do not exhibit mixing, but rearrangement within a few atomic layers at the interface results in enhanced adhesion and no aggregation upon annealing at moderate temperatures.

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