Production of hollow metal articles

Abstract

Abstract 860,126. Making turbine blades; casting; cores and fillings. WIGGIN & CO. Ltd., H. June 18, 1957 [June 20, 1956], No. 19129/56. Classes 83 (1), 83 (2) and 83 (4). In a method of making a hollow metal article, metal 4 is cast around a preformed malleable insert 2 to form a billet which is reduced by hot-working, so forming a blank, Fig. 3, or a final product, the insert 2 then being removed. A billet of nickel-chromium or nickel-chromiumcobalt alloy is cast about an insert, e.g. an ironmanganese-titanium alloy casting or a sintered insert of. iron and magnesia, the metal grain being refined during casting by sonic or ultrasonic vibration, by seeding, or by low-temperature casting. Alternatively, the insert may be frangible, e.g. silica or zirconia, in which case it is replaced by a malleable filling prior to partial extrusion of the billet to form a blank for a turbine blade. The blade is finished by machining, or the blade-blank may be hot-rolled to a taper from root to tip, Fig. 7. The insert is finally removed by acid-leaching. In a modification, the insert is shorter than the blade, and after partial extrusion of the billet, the metal beyond the insert is forged in two stages to form a shroud. In another modification, a billet for a number of blades is totally extruded and cut into slugs, which are machined to dumbell form, Fig. 17, prior to forging and machining the blade to aerofoil shape. Specifications 763,115 and 765,199 are referred to.

Inventors

• 👤 Harold W G Hignett
• 👤 Philip G Turner

Bibliographic Details