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Artículo
Tailoring of magnetocaloric response in nanostructured materials: Role of anisotropy
(2008-03-25)
The magnetocaloric response of an ensemble of oriented uniaxial magnetic objects, perpendicularly magne- tized to their easy axes, for temperatures close to the blocking temperature is calculated with the aim of demonstrating ...
Artículo
Mechanical alloying of Fe100−x−yNbxBy (x = 5, 10; y = 10, 15): from pure powder mixture to amorphous phase
(Elsevier, 2008)
The mechanical alloying process of Fe75Nb10B15 and Fe85Nb5B10 systems has been studied from an initial mixture of elemental powders. The amorphization process is monitored by X-ray diffraction and Mössbauer spectrometry. ...
Artículo
An Equivalent Time Approach for Scaling the Mechanical Alloying Processes
(Elsevier, 2008)
Dynamics of a single ball into a planetary ball mill is analyzed leading to a cubic dependence of the power transferred during milling with the rotational speed, Ω. This leads to the definition of an equivalent time to ...
Artículo
Nanocrystallization effects on the specific heat of fe-co-nb-b amorphous alloy
(Elsevier, 2008)
Specific heat at constant pressure, CP, was measured on amorphous, nanocrystalline and fully crystalline samples of Fe60Co18Nb6B16 alloy. Magnetic and calorimetric measurements agree, describing a continuously decreasing ...
Artículo
Magnetocaloric response of FeCrB amorphous alloys: Predicting the magnetic entropy change from the Arrott–Noakes equation of state.
(AIP Publishing, 2008)
The magnetic entropy change in Fe92−xCr8Bx x=12,15 amorphous alloys has been studied. Increasing the B content, both the peak entropy change and the Curie temperature of the alloy increase. This is in agreement with ...
Artículo
Instantaneous growth approximation describing the nanocrystallization process of amorphous alloys: A cellular automata model
(Elsevier, 2008-07)
A cellular automata simulation based on an instantaneous growth approximation is developed to model the nanocrystallization kinetics. In this frame, the time required for a nucleus to grow up to its maximum size is ...
Artículo
Magnetic permeability of ( Fe Co Ge ) 88 Zr 6 B 5 Cu 1 alloys: Thermal stability in a wide temperature range.
(AIP Publishing, 2008)
Temperature dependence, from room temperature up to 1000 K, of the initial permeability of Fe83−xCoxGe5Zr6B5Cu1 x=5 and 20 alloys at different stages of devitrification is reported. As nanocrystallization progresses, ...
Artículo
Influence of Ge addition on the magnetocaloric effect of a Co-containing Nanopermtype alloy.
(AIP Publishing, 2008)
The influence of the partial substitution of B by Ge on the magnetocaloric response of Fe78Co5Zr6B10Cu1 is studied. Ge addition produces a reduction in the temperature at which the peak entropy change takes place, as ...
Artículo
A phenomenological fitting curve for the magnetocaloric effect of materials with a second-order phase transition
(AIP Publishing, 2008-06-02)
The magnetic entropy change of polycrystalline samples Gd, La(Fe0.92Co0.08)11.83Al1.17, LaFe10.8Si2.2, Mn5Ge2.7Ga0.3, Nd2AlFe13Mn3, and TbCo2 with a second-order phase transition has been investigated. A uniform phenomenological ...
Artículo
High Temperature Coercivity of Nb-containing HITPERM Alloys: Effect of Cu Addition
(Elsevier, 2008)
Hysteresis loops of nanocrystalline samples of Fe39Co39Nb6B16 - yCuy (y = 0, 1) HITPERM-type alloys were measured from room temperature up to 773K. The alloy with Cu shows a nearly constant value of coercivity (∼ 135A/m) ...