Showing papers on "Spray forming published in 1988"

Cast metal matrix composites

Abstract: Metal matrix composites have been available in certain forms for at least two decades, e.g. boron fibre reinforced aluminium and various dispersed phase alloys and cermets. Recently, a range of alumina and silicon carbide fibres, whiskers, and particles with diameters <20 μm have become available. The possibilities of incorporating these materials into metals to improve stiffness, wear resistance, and elevated temperature strength without incurring weight penalties have attracted the attention of design engineers in the aerospace and automobile industries. The aim of the present paper is to outline the manufacturing processes for such composites, in particular those based upon liquid metal technology, e.g. squeeze casting and spray forming. Some of the mechanical and physical properties which have been determined for these materials are described. An analysis of how matrix alloy selection may influence tensile and fracture behaviour of short fibre and particle reinforced composites is attempted.MS...

Spray Forming Alloy 625 Marine Piping

Abstract: Near-net-shape manufacturing methods for large-diameter Alloy 625 piping have been evaluated to determine cost advantages and product quality over conventional manufacturing and powder metallurgy technologies. One particular method, Osprey spray forming, has proven itself to be a viable alternative. The sprayformed preforms exhibit uniform, equiaxed microstructures and mechanical properties approaching those of wrought via spray forming possesses mechanical properties surpassing those established by current specifications while the microstructures remain fine and quite uniform after cold rolling. In addition, a cost evaluation indicates sizable potential savings when Alloy 625 is produced by spray forming.

Spray-formed high-strength superalloys

Abstract: Five commercial nickel-base super-alloys, Rene’95, AF115, AF2-lDA, Astroloy, and MERL 76, were spray-formed into disk preforms. Metallurgical evaluation and hightemperature deformation studies were performed on the as-sprayed materials. Spray forming offers these super-alloys the advantages of rapid solidification: segregation-free, uniform structure with a fine grain size. The preforms demonstrated good forgeability even without superplasticity in the as-sprayed condition. All alloys were press-forged and supersolvusannealed. High-temperature strengths and stress rupture properties were compared, and AF115 shows the best temperature capability.