The relationship of microstructure and magnetic properties in cold-rolled 6.5% Si-Fe alloy

Pt/Co ultrathin multilayer films are a new candidate for magneto-optical (MO) recording devices. We have previously shown that their magnetic properties are improved by sputtering them with either Kr or Xe instead of Ar. Specifically, Arsputtered films have too small coercivity for recording. In this study we demonstrate that high resolution electron microscopy (HREM) is a powerful technique to study the relationship of the multilayer microstructure and magnetic properties. We used a Philips CM30 and a JEM 2000FX microscope to study multilayers with a typical total thickness in the 10 nm range, consisting of only 1-2 atomic layers of Co and 4-6 atomic layers of Pt.Figure 1 compares the cross sectional microstructure of nearly identical Pt/Co multilayers (~10x[4Å Co+13Å Pt]) sputtered in (A) 7 mTorr of Ar, (B) 7 mTorr of Kr, and (C) 5 mTorr of Xe. The layers sputtered in Ar are extremely flat and continuous. Sputtering with a larger mass gas (Kr or Xe) progressively increased the layer roughness, and the lateral continuity of layers was more frequently interrupted by grain boundaries, which were very distinct in Kr- and Xe-sputtered films compared to Ar-sputtered films.

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Synthesis and Characterization of the First 1:2 Ordered Perovskite Ruthenate

MRS Proceedings ◽

10.1557/proc-718-d1.3 ◽

2002 ◽

Vol 718 ◽

Author(s):

Job Rijssenbeek ◽

Sylvie Malo ◽

Takashi Saito ◽

Vincent Caignaert ◽

Masaki Azuma ◽

...

Keyword(s):

Magnetic Properties ◽

Neutron Diffraction ◽

Structure Type ◽

Synthesis And Characterization ◽

Neutron Diffraction Data ◽

X Ray ◽

Relationship Of ◽

The Relationship ◽

Perovskite Lattice

AbstractPerovskite-like mixed metal ruthenates are of interest owing to their varied electronic and magnetic properties, which are heavily dependent on the ordering of the transition metals. We report the synthesis and structural characterization of the first 1:2 ordered perovskite ruthenate, Sr3CaRu2O9. The structure was determined from a combination of powder X-ray, electron and neutron diffraction data and is characterized by a 1:2 ordering of Ca2+ and Ru5+ over the sixcoordinate B-sites of the perovskite lattice. Sr3CaRu2O9 is the first example of this structure-type to include a majority metal with d electrons (Ru(V), d3). The relationship of this material to the K2NiF4-type Sr1.5Ca0.5RuO4 (i.e., Sr3CaRu2O8) highlights the dramatic effects of the ruthenium valence on the resultant structure. Remarkably, these two structures can be quantitatively interconverted by the appropriate choice of reaction temperature and atmosphere.

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Nd7,33Ta8O28CI6 — ein Zwischenprodukt des thermischen Abbaus von Nd2Ta2O7Cl2: Präparation, Struktur und magnetische Eigenschaften / Nd7,33Ta8O28Cl6 — an Intermediate Product of the Thermal Decomposition of Nd2Ta2O7Cl2: Preparation, Crystal Structure and Magnetic Properties

Zeitschrift für Naturforschung B ◽

10.1515/znb-1988-1208 ◽

1988 ◽

Vol 43 (12) ◽

pp. 1567-1574 ◽

Cited By ~ 6

Author(s):

U. Schaffrath ◽

R. Gruehn

Keyword(s):

Crystal Structure ◽

Thermal Decomposition ◽

Magnetic Properties ◽

Calculated Data ◽

Chemical Transport ◽

Structure Type ◽

Magnetic Susceptibilities ◽

Relationship Of ◽

The Relationship ◽

Preparative Route

Abstract Single crystals of the new oxochlorotantalate Nd7.33Ta8O28Cl6, could be obtained only by chemical transport reactions (T2 → T1; T2 - 1000 °C, T, = 900 °C) with mixtures of Cl2/TaCl5 as transport agent. NdTaO4 was chosen as the starting material. A direct preparative route to Nd7.33Ta8O28Cl6 from binary and ternary components, however, was not successful. Nd7.33Ta8O28Cl6 , crystallizes in the space group Cmmm with a = 10.3381(8) Å, b = 18.865(1) Å, c - 3.9152(3) A; Z = 1. The structure was refined to R - 4.42%, R w = 2.76%. Main building units are pairs of edge-sharing TaO6 -octahedra which are connected with threefold capped trigonal prisms around Nd. Especially remarkable is one Nd position with an occupation factor of 0.833. The relationship of this new structure type with Nd2Ta2O7Cl2 is considered. Furthermore, we have measured the magnetic susceptibilities of both Nd-compounds in a temperature range from 3,6 to 251,3 K. The results are compared with calculated data.

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Effects of Sputtering Conditions on Texture, Microstructure and Magnetic Properties of the CoCrPt/NiAl Thin Films

MRS Proceedings ◽

10.1557/proc-517-199 ◽

1998 ◽

Vol 517 ◽

Cited By ~ 3

Author(s):

Y.-N. Hsu ◽

D. E. Laughlin ◽

D. N. Lambeth

Keyword(s):

Thin Films ◽

Grain Size ◽

Magnetic Properties ◽

Optimum Pressure ◽

Grain Sizes ◽

Maximum Value ◽

Sputtering Power ◽

Sputtering Pressure ◽

The Relationship ◽

Microstructure And Magnetic Properties

AbstractThe effects of sputtering argon pressures and sputtering power on the microstructure, texture and magnetic properties of NiAI underlayers on CoCrPt films were investigated. In this paper, the relationship between the sputtering conditions, microstructure, crystallographic texture and magnetic properties of these thin films will be discussed. By controlling the sputtering pressure and sputtering power, the texture and microstructure of NiAI underlayers were found to vary. This in turn was found to influence the magnetic properties of CoCrPt thin films. It was found that 10 mtorr is the optimum pressure to deposit the NiAl thin films to obtain the best magnetic properties for our system. At this argon pressure, the coercivity reached a maximum value because of the strongest CoCrPt (1010) texture and smallest grain size. At lower argon pressures (< 10 mtorr), NiAI tended to have a (110) texture reducing the CoCrPt (1010) texture, which in turn reduced the CoCrPt coercivity and S*. Also, high NiAl deposition pressures (>30 mtorr) yielded larger grains and a weaker CoCrPt (1010) texture, thereby decreasing the coercivity of the CoCrPt films. Increasing the sputtering power has been found to increase the CoCrPt coercivity and S* value. However, the grain sizes of the CoCrPt/NiAl thin films deposited at higher sputtering power were larger than those obtained at lower sputtering power.

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(The relationship between microstructure and magnetic properties in high-energy permanent magnets characterized by polytwinned structures)

10.2172/5133101 ◽

1992 ◽

Author(s):

Keyword(s):

Magnetic Properties ◽

Permanent Magnets ◽

High Energy ◽

The Relationship ◽

Microstructure And Magnetic Properties

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Relationship between Microstructure and Magnetic Properties of Nano-Scale Particles Formed in Cu-Ni-(FeCo) Alloys

Materials Science Forum ◽

10.4028/www.scientific.net/msf.941.1324 ◽

2018 ◽

Vol 941 ◽

pp. 1324-1329 ◽

Cited By ~ 1

Author(s):

Shintaro Matai ◽

Hibiki Sakakura ◽

Mahoto Takeda

Keyword(s):

Magnetic Properties ◽

Quantum Interference ◽

Magnetic Particles ◽

Superconducting Quantum Interference Device ◽

Recording Technology ◽

Treatment Conditions ◽

Transmission Electron ◽

Feco Alloys ◽

The Relationship ◽

Microstructure And Magnetic Properties

Numerous studies have been conducted to develop next-generation recording technology in spintronics. Because ultrafine magneitc particles are vital components of the technology, the interplay between the microsturcture and magnetic properties has attracted attention extensively in recent years. We focused on the relationship between the microstructure and magnetic properties of Cu-Ni-X (X=Fe, Co, FeCo) alloys comprising nanogranular magnetic particles. In this work, we prepared Cu-20 at% Ni-5 at% (FeCo), Cu-20 at% Ni-5 at% Fe, Cu-20 at% Ni-5 at% Co and examined the changes of microstructure and magnetic properties associated with heat treatments and composition. To examaine microstructural evolution of the alloy specimens, we conducted transmission electron microscope observations (TEM) with the as-quenched specimens and those aged at at 773-1073 K. We also carried out magneto-thermo gravimetry (MTG) measurements, superconducting quantum interference device (SQUID) measurements, magnetoresistance (MR) measurements and first-principles calculations based on the Koster-Korringa-Rostker (KKR) method with the Coherent Potential Approximation (CPA), to investigate the magnetic properties. The present work confirmed that the microstructure significantly changed, depending on the composition and heat treatment conditions. The present work also revealed that the magnetic properties closely correlated with the microstructure of samples.

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Optimal diamagnetic dilution concentration for suppressing the dipole–dipole interaction in single-ion magnets

Dalton Transactions ◽

10.1039/c9dt04403e ◽

2020 ◽

Vol 49 (7) ◽

pp. 2159-2167 ◽

Cited By ~ 1

Author(s):

Zhao-Bo Hu ◽

Xin Feng ◽

Jing Li ◽

Yi-Quan Zhang ◽

Lei Yin ◽

...

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Single Crystal ◽

Dipole Interaction ◽

Single Crystal Structure ◽

Dipole Field ◽

Relationship Of ◽

The Relationship

The relationship of magnetic properties and diamagnetic dilution has been studied for five-coordinate Co(ii) complex. It is found that the optimal dilution concentration to restrain dipole field can be given only by the single crystal structure.

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