Tender for the Supply and Installation of a Bridgman Furnace

Tender description

Supply and Installation of a Bridgman Furnace The University of Birmingham invites tenders for the supply of a high specification vertical Bridgman-Stockbarger furnace, with a maximum operating temperature of 1700°C or greater, for the solidification and growth of single crystals of 12 mm diameter over a wide range of growth rates, including quenching capability. The specification below outlines the requirements for a Bridgman-Stockbarger furnace that will be used to solidify samples for academic research. The core uses are twofold: 1. The production of high-purity, homogeneous single crystals across a wide spectrum of materials systems, from tin alloys and aluminium alloys to MnSi, FeGa alloys and rare-earth transition metals (e.g. DyFe2). The furnace must therefore allow different crucible materials and types, and operate over a wide range of growth temperatures, with controlled, slow withdrawal rates of typically 0.03 mm min-1. The supplier should detail which crucible materials are possible and indicate the costs of crucibles and their suppliers. To produce single crystals in non-equilibrium structures, the furnace must be capable of rapidly quenching its charge. To achieve high-purity, the sample chamber should be leak-tight under vacuum and have a gas-handling system for backfilling of inert gas atmospheres. 2. The study of dendritic growth and solidification kinetics in selected systems e.g. nickel superalloys. Here high withdrawal rates (typically 3 mm min-1) and large thermal gradients (200°C cm-1 or greater) are required, with a long charge length (45 cm or greater). Quenching is necessary to freeze in dendrite structures. Different technical solutions are evidently possible to realise the quenching requirement e.g. among others, dropping into a liquid metal bath or through a rapid motion into a snug-fit cooled jacket. If the supplier opts for the latter, it should be noted that this must be optimised for at least two charge (i.e. inner crucible) diameters: 6mm and 12mm. This could be achieved with, for example, a removable copper insert in the quench zone.