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In order to gain access to the booster and main explosive charges of PLAB-250-120 aerial depth bombs, i.e. the TNT charge and the TGAF-5M explosive composition of TNT, hexogen (RDX), aluminum powder and phlegmatizing agent respectively, Explosively Generated Plasma (EGP) devices were used to perforate their steel bodies. EGP devices were made in two versions. The first used a cylindrical TNT charge, while the second used a cylindrical charge shaped from SEMTEX PW4 plastic explosive. The explosive charges were supported by waveguides with conical cavities tapering towards the bomb. The structural components of the EGP devices, i.e. the bodies housing the explosive charges and the waveguides, were made of plastic by 3D printing. The effects of the EGP on the bomb were studied depending on the explosive material used, its mass and the distance of the EGP device waveguide from the side surface of the bomb. Simultaneous firing of an array of two EGP devices inserted with SEMTEX PW4 explosive, contacted their waveguides with the bomb, resulted in its detonation, while simultaneous firing of the analogous array of the same type two EGP devices inserted with SEMTEX PW4 explosive, with their waveguides at a distance of 10 mm from the bomb, resulted in perforation of two circular through-holes in the bomb body. Firing single EGP device inserted with TNT, being in contact through its waveguide with the body of the bomb, resulted in local rupture of the bomb body with crushing the bomb explosive charges, so allowing easy access to bomb explosive charges and sampling them. [ABSTRACT FROM AUTHOR]

Investigates the structural and chemical characteristics of Fe[sub x]Mn[sub 1-x] alloys in superlattices with iron contents of x=0.3, 0.5 and 0.9. Use of high resolution transmission electron microscopy and electron energy loss spectroscopy techniques; Achievement of pseudomorphic growth of the alloy on Ir for x equals or more than 0.5.

Deals with a study which examined the thermal behavior of xanthosine/carbon multilayers, the layers made of tungsten, nickel or silicon-tungsten-silicide alternating with carbide or pure carbon. Types of annealing performed in the multilayers; Thermal stability and diffusion mechanism of the multilayers; Reflectivity evolution.

Analyzes the multilayers consisting of alternating thin bilayers of tungsten and silicon by x-ray scattering and cross-sectional transmission electron microscopy observations. Diagram of the magnetron system; Geometry of the multilayer laser irradiation; Results; Discussion.

Measures the interdiffusivity and chemical ordering in amorphous iron[sub70]silicon (Si)[sub30]/Si thin films from the decay of satellite intensities of x-ray scattering peak during isothermal anneals. Values of the diffusivity for the amorphous alloy; Sample preparation of the experiment; Decay rate for the composition modulation.

Presents a study that examined magnetic and structural properties of iron nitride thin films obtained by reactive radio-frequency sputtering of an iron target in an argon-nitrogen plasma. Evaluation of the crystallographic structure of the thin film; Correlation between the saturation magnetization and nitrogen to argon ratio of the thin film; Analysis of the magnetic anisotropy and coercivity of the thin films.

Investigates Raman scattering from carbon in tungsten/carbon multilayer films. Role of carbon layers in period expansion after annealing in tungsten/carbon multilayer films; Factor which causes a decrease in the density of carbon layer; Decomposition of Raman spectra.

Presents a study that examined the fabrication of tungsten (W)/carbon (C) multilayers using a magnetron sputtering device. Use of x-ray scattering and Raman spectroscopy; Discussion on the performances and thermal stability of W/C multilayers; Calculation of the molar volume of pure W and C compounds.

A study of exchange bias phenomenon in ferrimagnetic /ferromagnetic FeGd/ FeSn bilayers is presented. The amorphous FeSn and FeGd alloys have been grown by co-evaporation. Specific growth conditions allow to induce an uniaxial anisotropy in both alloys in a parallel direction. After saturation of the bilayers under a positive field, the hysteresis loop of one of the layer is shifted towards a positive field HE. The sign of the exchange bias field HE is shown to be due to the antiferromagnetic coupling between the net magnetizations of both alloys. The field HE is studied as a function of the thickness of each layer and of the temperature. Using ac-susceptibility measurements and polarized neutron reflectometry, it is shown that the reversal of magnetization of the bilayers is dominated by the presence of a domain wall at the interface. This exchange bias system is shown to act as a potential well for the magnetic domain wall. Within this assumption and thanks to a precise magnetic characterization of each alloy, the evolution of HE with the thickness of the layers is well reproduced using simple one-dimensional analytical models for the domain wall or a more elaborate numerical approach. [ABSTRACT FROM AUTHOR]

This study is dedicated to the growth of bcc Mn by molecular beam epitaxy, in order to look at the magnetic properties of bcc Mn near room temperature. For this purpose, Mn is deposited on bcc MxV1-x(001) alloy lattices (M = Fe or Nb) for which the lattice spacing is tunable by varying the concentration x. We first show that the parameter of the MxV1-x alloy's buffer layers can be adjusted from 2.95 Å to 3.3 Å depending on x and M. Three different structures in Mn films grown on these buffer layers are observed depending on the in-plane spacing of the initial MxV1-x lattice. Thick Mn films are always found to grow epitaxially in the Mn structure. For moderate thicknesses larger than 4 atomic planes, Mn grows in an unidentified structure. Finally, up to four deposited atomic planes, Mn is found to grow in a tetragonal structure close to a bcc one on Fe(001), FexV1-x(001) and NbxV1-x(001) for . This tetragonal structure is shown to be a distorsion of a Mn bcc structure with . Except for ultra-thin Mn films deposited on Fe(001), no macroscopic magnetization is detected in our strained bcc Mn samples. These results are compared to theoretical predictions. [ABSTRACT FROM AUTHOR]

The synthesis of a new BCT Fe phase was performed in Fe/Ir(100) superlattices grown by MBE. Magnetic properties of Fe/Ir(100) superlattices with 4 ml Fe and variable Ir thickness (2-30 Å) are investigated by Fe conversion electron Mössbauer spectroscopy in the 4.2-300 K temperature range. Two spectral components are evidence, related, respectively, to Fe atoms involved in the central part of the iron layers and at the interface between iron and iridium layers. The appearance of a high magnetic hyperfine splitting in the iron BCT structure above a volume threshold of 12 Å is evidenced. Marked differences are observed between the mean magnetic properties and the local ones suggesting strong relaxation effects. [ABSTRACT FROM AUTHOR]

Presents an abstract of a study that examined [sup59]cobalt (Co) and [sup119]tin (Sn) hyperfine fields in amorphous CoSn alloys.