Bernard Vinet

Surface Tension Measurements on Industrial Alloys by the Drop-Weight Method

The drop-weight method has been successfully applied to a representative set of industrial alloys (W–Re26, Mo–Re50, Pt–Rh10, Pt–Rh30, Ti–Al6–V4, AISI 316 L stainless steel, INCONEL 182 and 600 alloys), with the result that very reproducible surface tension measurements (Δ σ/σ<0.5%) have been established for these materials at the liquidus temperature. This work supports the idea that the simplicity of the drop-weight method should attract much more attention for production control or to provide reference values at the liquidus temperature, although it cannot be used for temperature coefficient measurements of the surface tension.

Undercooling experiments on niobium–rhenium alloys from drop-tube processing

Abstract After studying nucleation and phase selection phenomena occurring in undercooled Re–W and Re–Ta alloys, attention is paid on the Nb–Re system where a compositional metastability of the σ phase is mainly identified. Some features on the growth of the complex σ and χ phases are also given.

Ab initio study of transitory metastable phases solidified by drop-tube processing

The solidification path of highly undercooled refractory metals and their alloys in an ultrahigh vacuum drop tube is shown to involve transitory metastable phases. First-principles calculations of the structural stability in these systems are developed to determine the possibility of obtaining metastable phases. We show that tetrahedrally close-packed (tcp) structures are good candidates to understand the origin of such metastable phases.