accelerated homogenization of a cast nickel-based superalloy vdm780 via thermomechanical processing

In recent years, the push to reduce fuel consumption and emissions in turbines, designs have focused on achieving higher operating temperatures, which require materials capable of sustaining elevated temperatures in industrial applications. the development and production of the nickel-base superalloy vdm780, with an operating temperature above 750 °c (nominally 780 °c), have been pursued to meet this demand. this superalloy is often considered a suitable alternative to inconel 718. the present study demonstrates the thermomechanical processing can significantly accelerate homogenization, enabling the production of a wrought structure in vdm780 with minimal heat treatment. a cast ingot of the vdm780 superalloy was first prepared using a vacuum induction melting (vim) furnace, without employing refining processes such as electroslag remelting (esr) or vacuum arc remelting (var). the conditions for homogenization and hot rolling were then investigated using simultaneous thermal analysis (sta). the results show that a homogenization temperature of 1160 °c provides adequate homogenization, resulting in a microstructure that is well-suited for workability.