The production of metallic fiber and filament directly from the melt has been practiced for some years. However, the application of these techniques has been limited due to materials-compatibility problems. Two new fiber-casting methods have been developed: Crucible Melt Extraction and Pendant Drop Melt Extraction. Both methods involve bringing the edge of a rotating disk into contact with a source of molten metal. Molten metal solidifies on the periphery of the disk, adheres there for a short time as it is removed from the melt source, and is then spontaneously released from the disk in the form of solid fiber. Both methods significantly reduce the technical difficulties heretofore associated with fiber casting and are amenable to operation in air, inert atmosphere, or vacuum. Metals as diverse as tin and niobium have been fiberized successfully.

SUMMARYA finite element code for steady-state hot rolling processes of rigid-visco-plastic materials under planestrain conditions was developed in a mixed Eulerian-Lagrangian framework. This special set up allows for a direct calculation of the local deformations occurring at the free surfaces outside the contact region between the strip and the work roll. It further simplifies the implementation of displacement boundary conditions, such as the impenetrability condition. When applied to different practical hot rolling situations, ranging from thick slab to ultra-thin strip rolling, the velocity-displacement based model (briefly denoted as vu-model) in this mixed Eulerian-Lagrangian reference system proves to be a robust and efficient method.The vu-model is validated against a solely velocity-based model (vv-model) and against elementary methods based on the Kármán-Siebel and Orowan differential equations. The latter methods, when calibrated, are known to be in line with experimental results for homogeneous deformation cases. For a massive deformation it is further validated against the commercial finite-element software package Abaqus/Explicit. It is shown that the results obtained with the vu-model are in excellent agreement with the predictions of the vv-model and that the vu-model is even more robust than its vv-counterpart. Throughout the study we assumed a rigid cylindrical work roll; only for the homogeneous test case, we also investigated the effect of an elastically deformable work roll within the frame of the Jortner Green's function method.The new modelling approach combines the advantages of conventional Eulerian and Lagrangian modelling concepts and can be extended to three dimensions in a straightforward manner.

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Ferromagnetic domain walls tend to move in phase with an alternating stress or magnetic field. This movement is opposed by directionally ordered interstitial atoms. When the time associated with the relaxation process is the order of the period of the moving walls, a phase lag between the applied field and the domainwall moveme~t occurs. This phase lag, coupled with normal hysteresis losses, causes a variety of magnetic and magnetoelastlc phenomena, among them a strong temperature dependence of the ac magnetic permeability ~nd a broa~ internal-fri~tion pe~k in the te~perature range of the Snoek peaks. These phenomena can be mterpreted I? te~ms of vIscoelastiC theory, wIth a relaxation process (interstitial directional ordering) having a umque actlVatIOn energy. 1