Thin workpieces with complex shape made by hot isostatic pressing - esp. aircraft nose cone made from titanium alloy powder in steel mould with outer deformable wall

摘要

Sinterable powder of grain size 0.1-1mm is made and fed into a mould formed by two parts (a,b). The thicker part (a) is not deformed by hot isostatic pressing (HIP), but the thinner part (b) is deformed during HIP. The mould is sealed, and the assembly is subjected to HIP, followed by removing the mould (a,b). The prod. is pref. machined on the surface which was next to mould part (b). The powder is pref. a metal or alloy, esp. a Ti alloy, fed into a steel mould and subjected to 50-200 MPa at 900-980 deg.C. for HIP. The deformable part (b) of the mould pref. has a wall thickness of 2-4mm, which is at least 0.5mm less than the wall thickness of part (a). The replacement of similar workpieces made by casting or forging and involving long and expensive machining operation.