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A powder-level, finite-element model is created to describe densification, as a function of applied stress during uniaxial hot pressing, of CP-Ti and Ti-6Al-4V powders with spherical or spheroidal shapes for various packing geometries. Two cases are considered: (1) isothermal densification (in the a-or b-fields of CP-Ti and in the b-field of Ti-6Al-4V) where power-law creep dominates and (2) thermal cycling densification (across the a/b-phase transformation of Ti-6Al-4V) where transformation mismatch plasticity controls deformation at low stresses. Reasonable agreement is achieved between numerical results and previously published experimental measurements and continuum modeling predictions.

Effects of transition metal substitution on the glass-formation ability and magnetic properties of Fe 62 Co 9.5 Nd 3 Dy 0.5 B 25 glassy alloy Smart susceptors are being developed for use as tooling surfaces in molding machines that use apply electro-magnetic induction heating to mold and form plastics or metal powders into structural parts, e.g., on aerospace and automotive manufacturing lines. The optimal magnetic materials for the induction heating process should have large magnetization, high magnetic permeability, but also small thermal expansion coefficient. The Fe 0.65 Ni 0.35 invar alloy with its negligible thermal expansion coefficient is thus a natural choice for this application. Here, we use density functional theory as implemented through the Korringa-Kohn-Rostoker method within the coherent-potential approximation, to design new alloys with the large magnetization desired for smart susceptor applications. We consider the Fe 0.65-x Ni 0.35-y M xþy alloys derived from Fe 0.65 Ni 0.35 invar adding a third element M ¼ Sc, Ti, V, Cr, Mn, or Co with concentration (x þ y) reaching up to 5 at. %. We find that the total magnetization depends linearly on the concentration of M. Specifically, the early 3d transition metals from Sc to Cr decrease the magnetization with respect to that of the invar alloy whereas Mn and Co increase it. V C 2015 AIP Publishing LLC. [http://dx.